{"id":242832,"date":"2025-12-08T09:42:26","date_gmt":"2025-12-08T08:42:26","guid":{"rendered":"https:\/\/emariete.com\/?p=242832"},"modified":"2026-02-16T02:22:28","modified_gmt":"2026-02-16T01:22:28","slug":"solar-panel-issues-low-power-esp32","status":"publish","type":"post","link":"https:\/\/emariete.com\/en\/problemas-paneles-solares-baja-potencia-esp32\/","title":{"rendered":"Low-Power Solar Panels: MPPT is the Secret to Running Your ESP32 on Just 1W"},"content":{"rendered":"<p class=\"wp-block-paragraph\">We've seen a lot of great home projects using <strong>solar panels<\/strong>But the reality is that energy efficiency is a battleground. If you have tried to power a <strong>ESP32<\/strong> or a <strong>Raspberry Pi<\/strong> with a <strong>small solar panel<\/strong> from <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-12cae0d6516f97a319f59aae47c1d2d5_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"1 W\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"27\" style=\"vertical-align: 0px;\"\/> and you have failed, you are not alone.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">This post complements our project on <strong><em>Enerlogic \u2014 Energy Wizard <\/em><\/strong>and explains the harsh truth we learnt: the energy of <strong>low-power solar panels<\/strong> requires a very high level of electronic intelligence to function properly.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"h-el-error-absurdo-por-que-no-debes-medir-tu-panel-en-miliamperios\">The Silly Mistake: Why You Should NOT Measure Your Panel in Milliamps<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Let's first establish something very important: what is useful for identifying the energy that a solar panel can generate and what is not.<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">It is very common to hear people say: \"My panel pulls out <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-00dd22794907b242b1fd3039b0205a70_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"500 mA\" title=\"Rendered by QuickLaTeX.com\" height=\"13\" width=\"56\" style=\"vertical-align: 0px;\"\/>\". This metric is <strong>completely inadequate<\/strong> to assess the performance of a <strong>solar panel<\/strong>. To say that a panel \"takes out\" <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-00dd22794907b242b1fd3039b0205a70_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"500 mA\" title=\"Rendered by QuickLaTeX.com\" height=\"13\" width=\"56\" style=\"vertical-align: 0px;\"\/> is like saying nothing.<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Short Circuit Current (<img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-c51055cb1978ebf3ca3f7cf32e9399cb_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"I_{sc}\" title=\"Rendered by QuickLaTeX.com\" height=\"15\" width=\"20\" style=\"vertical-align: -3px;\"\/>):<\/strong> The value that many people measure with an ammeter is the short circuit current (<img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-c51055cb1978ebf3ca3f7cf32e9399cb_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"I_{sc}\" title=\"Rendered by QuickLaTeX.com\" height=\"15\" width=\"20\" style=\"vertical-align: -3px;\"\/>), which is the maximum current that the panel can deliver <strong>with no load (voltage at zero or near zero).<\/strong> This current is useless for charging anything!<\/li>\n\n\n\n<li><strong>Current in the MPP (<img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-dfe25d8170c00c2f8c0029a1b7a9681a_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"I_{mpp}\" title=\"Rendered by QuickLaTeX.com\" height=\"18\" width=\"34\" style=\"vertical-align: -6px;\"\/>):<\/strong> This is the current delivered at the point of maximum power.<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">The only metric that really matters is the <strong><a href=\"https:\/\/es.wikipedia.org\/wiki\/Vatio\" target=\"_blank\" rel=\"noreferrer noopener\">Power in Watts (<img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-183777ab9133546b80b6f342c6ec9919_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"W\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"19\" style=\"vertical-align: 0px;\"\/>)<\/a><\/strong>as the watts combine both the current (<img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-14b16a74c9ddcc6f9be3e94b9c8d8f08_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"I\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"9\" style=\"vertical-align: 0px;\"\/>) as well as the voltage (<img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-54e215a7a583b4f357a5a627420bcf2f_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"V\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"14\" style=\"vertical-align: 0px;\"\/>).<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><p class=\"ql-center-displayed-equation\" style=\"line-height: 12px;\"><span class=\"ql-right-eqno\"> &nbsp; <\/span><span class=\"ql-left-eqno\"> &nbsp; <\/span><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-c3249f1fb023c90dda75263a7f02f12c_l3.png\" height=\"12\" width=\"82\" class=\"ql-img-displayed-equation quicklatex-auto-format\" alt=\"\\[P = V \\times I\\]\" title=\"Rendered by QuickLaTeX.com\"\/><\/p><\/p>\n\n\n\n<p class=\"wp-block-paragraph translation-block\">A <strong><img src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-12cae0d6516f97a319f59aae47c1d2d5_l3.svg\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"1 W\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"27\" style=\"vertical-align: 0px\"><\/strong> can give <img loading=\"lazy\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-e348b7555187665fb8cf75f7b7fb51b5_l3.svg\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"0.2 A\" title=\"Rendered by QuickLaTeX.com\" height=\"13\" width=\"36\" style=\"vertical-align: 0px\"> a <img loading=\"lazy\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-a1eb81e01eec640e2afca87295ee8445_l3.svg\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"5 V\" title=\"Rendered by QuickLaTeX.com\" height=\"13\" width=\"23\" style=\"vertical-align: 0px\"> o <img loading=\"lazy\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-2ffe43d55d6411918e14c9b44a477793_l3.svg\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"0.1 A\" title=\"Rendered by QuickLaTeX.com\" height=\"13\" width=\"36\" style=\"vertical-align: 0px\"> to <img loading=\"lazy\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-6084737b5d17639b17c8e850e7c7a113_l3.svg\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"10 V\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"31\" style=\"vertical-align: 0px\">. Both combinations give <img src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-12cae0d6516f97a319f59aae47c1d2d5_l3.svg\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"1 W\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"27\" style=\"vertical-align: 0px\">, but the working voltage is <strong>completely different<\/strong>. Whichever system you use (charger, battery) only works if it receives the correct combination of <img loading=\"lazy\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-54e215a7a583b4f357a5a627420bcf2f_l3.svg\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"V\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"14\" style=\"vertical-align: 0px\"> e <img loading=\"lazy\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-14b16a74c9ddcc6f9be3e94b9c8d8f08_l3.svg\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"I\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"9\" style=\"vertical-align: 0px\">.<\/p>\n\n\n\n<div class=\"wp-block-group has-global-color-8-background-color has-background\"><div class=\"wp-block-group__inner-container is-layout-constrained wp-block-group-is-layout-constrained\">\n<h3 class=\"wp-block-heading\" id=\"h-aqui-tienes-la-prueba-real-realizada-por-mi\"><strong>Here is the real test, carried out by me<\/strong><\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">I am using a <a href=\"https:\/\/s.click.aliexpress.com\/e\/_c3KDD2qD\">6V 1W 110 x 60mm solar panel bought on AliExpress (click here to see it)<\/a>.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">I measure the voltage supplied by the solar panel without load: <strong><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-dc791d3adea5ea654ef9fb18fa71097c_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"7.1 V\" title=\"Rendered by QuickLaTeX.com\" height=\"13\" width=\"37\" style=\"vertical-align: 0px;\"\/><\/strong><\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"541\" src=\"https:\/\/emariete.com\/wp-content\/uploads\/2025\/12\/Voltaje-abierto-Pruebas-panel-110x60-1W-08122025-1024x541.jpg\" alt=\"Hand holding a small rectangular solar panel connected with red and black wires to the tips of a red digital multimeter placed on a white surface, with background greenery and the multimeter display showing a reading.\" class=\"wp-image-242872\" srcset=\"https:\/\/emariete.com\/wp-content\/uploads\/2025\/12\/Voltaje-abierto-Pruebas-panel-110x60-1W-08122025-1024x541.jpg 1024w, https:\/\/emariete.com\/wp-content\/uploads\/2025\/12\/Voltaje-abierto-Pruebas-panel-110x60-1W-08122025-300x158.jpg 300w, https:\/\/emariete.com\/wp-content\/uploads\/2025\/12\/Voltaje-abierto-Pruebas-panel-110x60-1W-08122025-768x406.jpg 768w, https:\/\/emariete.com\/wp-content\/uploads\/2025\/12\/Voltaje-abierto-Pruebas-panel-110x60-1W-08122025.jpg 1333w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">I measure the amperage supplied by the shorted solar panel: <strong><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-4b82981834774cf5c390d77550ab840a_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"0.115 A\" title=\"Rendered by QuickLaTeX.com\" height=\"13\" width=\"54\" style=\"vertical-align: 0px;\"\/><\/strong><\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"578\" src=\"https:\/\/emariete.com\/wp-content\/uploads\/2025\/12\/Corriente-corto-Pruebas-panel-110x60-1W-08122025-1024x578.jpg\" alt=\"Rectangular solar cell held by a hand with probes attached and a red digital multimeter in the background showing approximately 11.5 V, taken in an outdoor environment.\" class=\"wp-image-242873\" srcset=\"https:\/\/emariete.com\/wp-content\/uploads\/2025\/12\/Corriente-corto-Pruebas-panel-110x60-1W-08122025-1024x578.jpg 1024w, https:\/\/emariete.com\/wp-content\/uploads\/2025\/12\/Corriente-corto-Pruebas-panel-110x60-1W-08122025-300x169.jpg 300w, https:\/\/emariete.com\/wp-content\/uploads\/2025\/12\/Corriente-corto-Pruebas-panel-110x60-1W-08122025-768x434.jpg 768w, https:\/\/emariete.com\/wp-content\/uploads\/2025\/12\/Corriente-corto-Pruebas-panel-110x60-1W-08122025-1536x867.jpg 1536w, https:\/\/emariete.com\/wp-content\/uploads\/2025\/12\/Corriente-corto-Pruebas-panel-110x60-1W-08122025-2048x1156.jpg 2048w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">According to this, and applying the power formula, which we have seen before (<em>P = V x I<\/em>), this panel can give: <strong>0,82W<\/strong> (not bad, right, it's not even a summer day, it's December!!!).<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">That is the theory. The reality is that <strong>when we make a proper curve IV<\/strong>, using my tool <strong><em>Enerlogic \u2014 Energy Wizard<\/em><\/strong>:<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"692\" height=\"562\" src=\"https:\/\/emariete.com\/wp-content\/uploads\/2025\/12\/Curva-IV-Pruebas-panel-110x60-1W-081220251340.png\" alt=\"Dark modal window with the graph &quot;Solar Panel I-V Curve&quot;: blue downward line for current (A), purple dotted line for power (W) with a peak towards 5-6 V and a red MPP marker at approximately 6.05 V with I\u22480.062 A and P\u22480.375 W.\" class=\"wp-image-242874\" srcset=\"https:\/\/emariete.com\/wp-content\/uploads\/2025\/12\/Curva-IV-Pruebas-panel-110x60-1W-081220251340.png 692w, https:\/\/emariete.com\/wp-content\/uploads\/2025\/12\/Curva-IV-Pruebas-panel-110x60-1W-081220251340-300x244.png 300w\" sizes=\"auto, (max-width: 692px) 100vw, 692px\" \/><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">The maximum power that this panel can generate when it is working at its best point (the \"MPP point\") is just <strong><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-446e8ed1a931120fdbd306a13a0593ea_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"0.38 W\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"51\" style=\"vertical-align: 0px;\"\/><\/strong>The average for the first time, it is not even half of what we measured before.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">It should also be noted that these conditions change rapidly. A couple of hours later, the same panel, in the same place (redirected again directly to the sun) generates an energy of only <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-660ce0beaf5a9363ec07189992ba9cfb_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"0.0196 W\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"69\" style=\"vertical-align: 0px;\"\/>The reason? It has become cloudy and the sun is lower...<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>In addition, the MPP voltage is now <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-41d4ee797688324e07969cf5745f32db_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"3.96 V\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"46\" style=\"vertical-align: 0px;\"\/>when it used to be <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-c1a52f2562437dd9168bd29246b43972_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"6.06 V\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"46\" style=\"vertical-align: 0px;\"\/><\/strong><\/p>\n\n\n\n<figure data-wp-context=\"{&quot;imageId&quot;:&quot;6a80994bc73ce&quot;}\" data-wp-interactive=\"core\/image\" data-wp-key=\"6a80994bc73ce\" class=\"wp-block-image size-full wp-lightbox-container\"><img loading=\"lazy\" decoding=\"async\" width=\"694\" height=\"563\" data-wp-class--hide=\"state.isContentHidden\" data-wp-class--show=\"state.isContentVisible\" data-wp-init=\"callbacks.setButtonStyles\" data-wp-on--click=\"actions.showLightbox\" data-wp-on--load=\"callbacks.setButtonStyles\" data-wp-on--pointerdown=\"actions.preloadImage\" data-wp-on--pointerenter=\"actions.preloadImageWithDelay\" data-wp-on--pointerleave=\"actions.cancelPreload\" data-wp-on-window--resize=\"callbacks.setButtonStyles\" src=\"https:\/\/emariete.com\/wp-content\/uploads\/2025\/12\/Curva-IV-Pruebas-panel-110x60-1W-081220251520.png\" alt=\"Graph in a window entitled &quot;Solar Panel I-V Curve&quot; showing the current curve (blue dotted line) descending versus voltage, the power curve (purple dotted line) in a bell shape and a red square marker indicating the maximum power point (MPP) around V\u22483.776 V, I\u22480.005 A, P\u22480.0196 W, with &quot;Generate I-V Curve&quot; and &quot;Close&quot; buttons at the bottom.\" class=\"wp-image-242885\" srcset=\"https:\/\/emariete.com\/wp-content\/uploads\/2025\/12\/Curva-IV-Pruebas-panel-110x60-1W-081220251520.png 694w, https:\/\/emariete.com\/wp-content\/uploads\/2025\/12\/Curva-IV-Pruebas-panel-110x60-1W-081220251520-300x243.png 300w\" sizes=\"auto, (max-width: 694px) 100vw, 694px\" \/><button\n\t\t\tclass=\"lightbox-trigger\"\n\t\t\ttype=\"button\"\n\t\t\taria-haspopup=\"dialog\"\n\t\t\tdata-wp-bind--aria-label=\"state.thisImage.triggerButtonAriaLabel\"\n\t\t\tdata-wp-init=\"callbacks.initTriggerButton\"\n\t\t\tdata-wp-on--click=\"actions.showLightbox\"\n\t\t\tdata-wp-style--right=\"state.thisImage.buttonRight\"\n\t\t\tdata-wp-style--top=\"state.thisImage.buttonTop\"\n\t\t>\n\t\t\t<svg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"12\" height=\"12\" fill=\"none\" viewbox=\"0 0 12 12\">\n\t\t\t\t<path fill=\"#fff\" d=\"M2 0a2 2 0 0 0-2 2v2h1.5V2a.5.5 0 0 1 .5-.5h2V0H2Zm2 10.5H2a.5.5 0 0 1-.5-.5V8H0v2a2 2 0 0 0 2 2h2v-1.5ZM8 12v-1.5h2a.5.5 0 0 0 .5-.5V8H12v2a2 2 0 0 1-2 2H8Zm2-12a2 2 0 0 1 2 2v2h-1.5V2a.5.5 0 0 0-.5-.5H8V0h2Z\" \/>\n\t\t\t<\/svg>\n\t\t<\/button><\/figure>\n<\/div><\/div>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Conclusion:<\/strong> High amperage with low voltage means <strong>unusable power<\/strong>. Always evaluate the performance of your <strong>solar panel<\/strong> and the consumption of your circuit in <strong>watts<\/strong> for the comparison to make sense.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"h-la-decepcion-de-la-potencia-nominal-el-factor-p-max-y-1000-w-m-2\">The Nominal Power Deception (The Factor <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-2071ac933025e66004c08c5c9ac1e363_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"P_{max}\" title=\"Rendered by QuickLaTeX.com\" height=\"15\" width=\"38\" style=\"vertical-align: -3px;\"\/> y <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-9847057d4733795589e2c8d2c2690a98_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"1000 W\/m\u00b2\" title=\"Rendered by QuickLaTeX.com\" height=\"20\" width=\"84\" style=\"vertical-align: -5px;\"\/>)<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">When you buy a panel of <strong><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-12cae0d6516f97a319f59aae47c1d2d5_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"1 W\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"27\" style=\"vertical-align: 0px;\"\/><\/strong>that figure (<img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-2071ac933025e66004c08c5c9ac1e363_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"P_{max}\" title=\"Rendered by QuickLaTeX.com\" height=\"15\" width=\"38\" style=\"vertical-align: -3px;\"\/>) is determined under ideal laboratory conditions, known as the <strong>STC<\/strong> (<em>Standard Test Conditions<\/em>): <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-59158eb535e0746de31f5fc4b553fae6_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"\\mathbf{1000 W\/m^2}\" title=\"Rendered by QuickLaTeX.com\" height=\"20\" width=\"95\" style=\"vertical-align: -5px;\"\/> of irradiance, <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-4ef36c450b3b0cb29143091dbd66825d_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"25\u00b0C\" title=\"Rendered by QuickLaTeX.com\" height=\"13\" width=\"39\" style=\"vertical-align: 0px;\"\/> temperature.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>In practice, these conditions are rarely met, and this is the biggest deception in solar sizing:<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Actual solar radiation is rare, <strong>if ever,<\/strong>reaches <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-59158eb535e0746de31f5fc4b553fae6_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"\\mathbf{1000 W\/m^2}\" title=\"Rendered by QuickLaTeX.com\" height=\"20\" width=\"95\" style=\"vertical-align: -5px;\"\/> used to calibrate the panels.<\/p>\n\n\n\n<div class=\"wp-block-group has-global-color-8-background-color has-background\"><div class=\"wp-block-group__inner-container is-layout-flow wp-block-group-is-layout-flow\">\n<p class=\"wp-block-paragraph\"><strong>Royal Example (Madrid, 7 December):<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The graph of the weather station at my home in Madrid, Spain, on 7 December 2025 (winter) shows that the maximum solar radiation reached was <strong><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-dacd06b4043cf8b4d84604bdb78dbd55_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"229.1 W\/m\u00b2\" title=\"Rendered by QuickLaTeX.com\" height=\"20\" width=\"90\" style=\"vertical-align: -5px;\"\/> at 14:20h<\/strong>and only for a brief moment.<\/p>\n\n\n\n<figure data-wp-context=\"{&quot;imageId&quot;:&quot;6a80994bc8b67&quot;}\" data-wp-interactive=\"core\/image\" data-wp-key=\"6a80994bc8b67\" class=\"wp-block-image size-large wp-lightbox-container\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"242\" data-wp-class--hide=\"state.isContentHidden\" data-wp-class--show=\"state.isContentVisible\" data-wp-init=\"callbacks.setButtonStyles\" data-wp-on--click=\"actions.showLightbox\" data-wp-on--load=\"callbacks.setButtonStyles\" data-wp-on--pointerdown=\"actions.preloadImage\" data-wp-on--pointerenter=\"actions.preloadImageWithDelay\" data-wp-on--pointerleave=\"actions.cancelPreload\" data-wp-on-window--resize=\"callbacks.setButtonStyles\" src=\"https:\/\/emariete.com\/wp-content\/uploads\/2025\/12\/Radiacion-Solar-07122025-1024x242.png\" alt=\"Line graph entitled &#039;Solar and UVI&#039; showing throughout the day a yellow curve of solar irradiance increasing from morning and reaching an abrupt peak of 229.1 W\/m\u00b2 at 14:20 (marked with an orange dot) and a blue line of UV index mostly at zero with a brief spike to 2 at the same time, with left (0-300 W\/m\u00b2) and right (0-2 UVI) vertical axes and a pop-up label indicating values at 07 Dec 2025 14:20.\" class=\"wp-image-242841\" srcset=\"https:\/\/emariete.com\/wp-content\/uploads\/2025\/12\/Radiacion-Solar-07122025-1024x242.png 1024w, https:\/\/emariete.com\/wp-content\/uploads\/2025\/12\/Radiacion-Solar-07122025-300x71.png 300w, https:\/\/emariete.com\/wp-content\/uploads\/2025\/12\/Radiacion-Solar-07122025-768x182.png 768w, https:\/\/emariete.com\/wp-content\/uploads\/2025\/12\/Radiacion-Solar-07122025.png 1252w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><button\n\t\t\tclass=\"lightbox-trigger\"\n\t\t\ttype=\"button\"\n\t\t\taria-haspopup=\"dialog\"\n\t\t\tdata-wp-bind--aria-label=\"state.thisImage.triggerButtonAriaLabel\"\n\t\t\tdata-wp-init=\"callbacks.initTriggerButton\"\n\t\t\tdata-wp-on--click=\"actions.showLightbox\"\n\t\t\tdata-wp-style--right=\"state.thisImage.buttonRight\"\n\t\t\tdata-wp-style--top=\"state.thisImage.buttonTop\"\n\t\t>\n\t\t\t<svg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"12\" height=\"12\" fill=\"none\" viewbox=\"0 0 12 12\">\n\t\t\t\t<path fill=\"#fff\" d=\"M2 0a2 2 0 0 0-2 2v2h1.5V2a.5.5 0 0 1 .5-.5h2V0H2Zm2 10.5H2a.5.5 0 0 1-.5-.5V8H0v2a2 2 0 0 0 2 2h2v-1.5ZM8 12v-1.5h2a.5.5 0 0 0 .5-.5V8H12v2a2 2 0 0 1-2 2H8Zm2-12a2 2 0 0 1 2 2v2h-1.5V2a.5.5 0 0 0-.5-.5H8V0h2Z\" \/>\n\t\t\t<\/svg>\n\t\t<\/button><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">If your panel is <strong><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-12cae0d6516f97a319f59aae47c1d2d5_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"1 W\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"27\" style=\"vertical-align: 0px;\"\/><\/strong> is based on <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-9847057d4733795589e2c8d2c2690a98_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"1000 W\/m\u00b2\" title=\"Rendered by QuickLaTeX.com\" height=\"20\" width=\"84\" style=\"vertical-align: -5px;\"\/>at the peak of that day you only received the <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-ad81f8f008ab191f42ed5f66d4102249_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"&#50;&#50;&#46;&#57;&#49;&#92;&#37;\" title=\"Rendered by QuickLaTeX.com\" height=\"15\" width=\"55\" style=\"vertical-align: -1px;\"\/> of the rated power (<img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-bfc083508d204fe29edb3fd328cfeec4_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"&#50;&#50;&#57;&#46;&#49;&#32;&#47;&#32;&#49;&#48;&#48;&#48;\" title=\"Rendered by QuickLaTeX.com\" height=\"19\" width=\"86\" style=\"vertical-align: -5px;\"\/>).<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">That is to say, <strong>your panel of <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-12cae0d6516f97a319f59aae47c1d2d5_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"1 W\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"27\" style=\"vertical-align: 0px;\"\/> only produced, at most, <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-be207f02f5dfbb916d5641032c8db4cb_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"\\mathbf{0.23 W}\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"56\" style=\"vertical-align: 0px;\"\/><\/strong>. And this was only at one point in the day, the rest of the day produced much less energy.<\/p>\n<\/div><\/div>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Temperature and Losses:<\/strong> High temperatures in the summer reduce the efficiency of the <strong>solar panel<\/strong> by itself.<\/li>\n\n\n\n<li><strong>Clouds and Dirt:<\/strong> Any partial shade or cloud cover drastically reduces production.<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Conclusion:<\/strong> Your panel of <strong><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-12cae0d6516f97a319f59aae47c1d2d5_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"1 W\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"27\" style=\"vertical-align: 0px;\"\/><\/strong> may only deliver <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-cbf3630d8318fd214314b76928353d7d_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"&#48;&#46;&#53;\" title=\"Rendered by QuickLaTeX.com\" height=\"13\" width=\"22\" style=\"vertical-align: 0px;\"\/> a <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-bd2e1c313d59acf6935fb50fac3ff7cc_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"0.8 W\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"42\" style=\"vertical-align: 0px;\"\/> in summer, let alone in <strong><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-3fb7f1f9c486c6d5de4f9542d6649a7d_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"0.2 W\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"42\" style=\"vertical-align: 0px;\"\/><\/strong> This difference is critical!<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"h-la-carga-critica-picos-de-consumo-y-corriente\">The Critical Load: Peak Power Consumption and Current<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Modern microcontrollers, especially those using wireless communication, are energy predators at times.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The <strong>ESP32<\/strong>for example, has a low baseline consumption, but when you activate the <strong>Wi-Fi<\/strong> to transmit data, consumption can spike significantly over a period of time.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">If your panel is <strong><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-12cae0d6516f97a319f59aae47c1d2d5_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"1 W\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"27\" style=\"vertical-align: 0px;\"\/><\/strong> a <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-a1eb81e01eec640e2afca87295ee8445_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"5 V\" title=\"Rendered by QuickLaTeX.com\" height=\"13\" width=\"23\" style=\"vertical-align: 0px;\"\/> gives you, nominally, <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-e348b7555187665fb8cf75f7b7fb51b5_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"0.2 A\" title=\"Rendered by QuickLaTeX.com\" height=\"13\" width=\"36\" style=\"vertical-align: 0px;\"\/> a <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-caeb1e8e22d8b05cbadde06ba68c86df_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"6 V\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"23\" style=\"vertical-align: 0px;\"\/>is this enough to <strong>charging the battery<\/strong> And feed that peak of <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-f634df348bb192e177bd4ffeb7778095_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"1 A\" title=\"Rendered by QuickLaTeX.com\" height=\"13\" width=\"21\" style=\"vertical-align: 0px;\"\/> or more?<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Most of the time, <strong>the answer is no<\/strong>. If the battery is not being recharged at a sufficient rate by the panel, the energy is progressively depleted and the system collapses.<\/p>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<p class=\"wp-block-paragraph\"><strong>Golden Rule:<\/strong> The panel does not power the circuit; <strong>the panel charges the battery, and the battery powers the circuit.<\/strong>. If the panel is too small, the battery will drain faster than it recharges.<\/p>\n<\/blockquote>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"h-como-medir-la-energia-real-y-hallar-el-mpp-con-un-multimetro\">How to Measure Real Energy and Find MPP with a Multimeter<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">If you don't have a curve analyser <em>I-V<\/em> costly, you can get a good estimate of the real power of your panel and its <strong>Maximum Power Point (MPP)<\/strong> using a multimeter and a variable resistor (or a resistor bank).<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Note that the resistor has to be able to dissipate the heat generated by this energy, so power resistors or a rheostat are normally used.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"h-paso-1-hallar-el-mpp-v-mpp-e-i-mpp\">Step 1: Find the MPP (<img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-82e71336aba0c7d7a113696dc9766062_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"V_{mpp}\" title=\"Rendered by QuickLaTeX.com\" height=\"18\" width=\"36\" style=\"vertical-align: -6px;\"\/> e <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-dfe25d8170c00c2f8c0029a1b7a9681a_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"I_{mpp}\" title=\"Rendered by QuickLaTeX.com\" height=\"18\" width=\"34\" style=\"vertical-align: -6px;\"\/>)<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">The aim is to find the exact point of voltage and current where the multiplication of both gives the highest value (<img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-2071ac933025e66004c08c5c9ac1e363_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"P_{max}\" title=\"Rendered by QuickLaTeX.com\" height=\"15\" width=\"38\" style=\"vertical-align: -3px;\"\/>).<\/p>\n\n\n\n<ol start=\"1\" class=\"wp-block-list\">\n<li><strong>Measure Voc:<\/strong> It measures the <strong>Open Circuit Voltage (<img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-98177521697f4f282c22deb7b6bb3ed6_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"V_{oc}\" title=\"Rendered by QuickLaTeX.com\" height=\"15\" width=\"23\" style=\"vertical-align: -3px;\"\/>)<\/strong> with the panel disconnected (no load, battery or charger connected). This sets the maximum possible voltage.<\/li>\n\n\n\n<li><strong>Add Variable Resistance:<\/strong> Connect a <strong>variable load resistor<\/strong> (or power potentiometer) to the panel outputs. This resistor simulates the demand of your charger. Make sure the resistor is powerful enough to dissipate the heat.<\/li>\n\n\n\n<li><strong>Iterative measurements:<\/strong> It adjusts the resistance in small steps and, at each step, it simultaneously measures the <strong>Voltage (<img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-54e215a7a583b4f357a5a627420bcf2f_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"V\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"14\" style=\"vertical-align: 0px;\"\/>)<\/strong> through resistance and <strong>Current (<img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-14b16a74c9ddcc6f9be3e94b9c8d8f08_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"I\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"9\" style=\"vertical-align: 0px;\"\/>)<\/strong> flowing through it.<\/li>\n\n\n\n<li><strong>Calculate Power:<\/strong> Use the formula <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-e457cb5b83dd7b16b1bcd8983b291cb7_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"P = V \u00d7 I\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"82\" style=\"vertical-align: 0px;\"\/> to calculate the power in watts at each measurement point.<\/li>\n\n\n\n<li><strong>Identify the PPM:<\/strong> The pair (<img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-54e215a7a583b4f357a5a627420bcf2f_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"V\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"14\" style=\"vertical-align: 0px;\"\/>, <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-14b16a74c9ddcc6f9be3e94b9c8d8f08_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"I\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"9\" style=\"vertical-align: 0px;\"\/>) resulting in the highest power (<img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-2071ac933025e66004c08c5c9ac1e363_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"P_{max}\" title=\"Rendered by QuickLaTeX.com\" height=\"15\" width=\"38\" style=\"vertical-align: -3px;\"\/>) is your <strong>MPP<\/strong>. This is the ideal voltage (<img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-82e71336aba0c7d7a113696dc9766062_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"V_{mpp}\" title=\"Rendered by QuickLaTeX.com\" height=\"18\" width=\"36\" style=\"vertical-align: -6px;\"\/>) that your shipper should try to maintain.<\/li>\n<\/ol>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"h-paso-2-medir-la-energia-total-generada-wh-dia\">Step 2: Measure Total Energy Generated (<img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-6c816194681f741087966b0d49975a33_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"Wh\/day\" title=\"Rendered by QuickLaTeX.com\" height=\"19\" width=\"61\" style=\"vertical-align: -5px;\"\/>)<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Energy is measured in watt-hours (<img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-75c02632c76ab1231d17c5cda0995f6c_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"Wh\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"29\" style=\"vertical-align: 0px;\"\/>), which is power (<img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-183777ab9133546b80b6f342c6ec9919_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"W\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"19\" style=\"vertical-align: 0px;\"\/>) per time (<img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-2ce27f7d2d82e3b238176ec7e7ee9118_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"h\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"10\" style=\"vertical-align: 0px;\"\/>).<\/p>\n\n\n\n<ol start=\"1\" class=\"wp-block-list\">\n<li><strong>Establishing the Charge:<\/strong> It uses a <strong>fixed resistor<\/strong> to simulate the load on your circuit, or simply connect your MPPT charger. Ideally, the load should maintain a voltage near the <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-82e71336aba0c7d7a113696dc9766062_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"V_{mpp}\" title=\"Rendered by QuickLaTeX.com\" height=\"18\" width=\"36\" style=\"vertical-align: -6px;\"\/> you found in Step 1.<\/li>\n\n\n\n<li><strong>Power Register:<\/strong> During a sunny day, take readings of <strong>Voltage (<img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-54e215a7a583b4f357a5a627420bcf2f_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"V\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"14\" style=\"vertical-align: 0px;\"\/>)<\/strong> y <strong>Current (<img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-14b16a74c9ddcc6f9be3e94b9c8d8f08_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"I\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"9\" style=\"vertical-align: 0px;\"\/>)<\/strong> at the panel output (or input to the charger) at fixed intervals, for example, <strong>every hour<\/strong> from 8:00h to 18:00h.<\/li>\n\n\n\n<li><strong>Calculate the Average Power:<\/strong> For each one-hour interval, calculate the Power (<img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-e457cb5b83dd7b16b1bcd8983b291cb7_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"P = V \u00d7 I\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"82\" style=\"vertical-align: 0px;\"\/>).<\/li>\n\n\n\n<li><strong>Sum of Energy:<\/strong> Sum the power of all the intervals to get the <strong>Total Daily Energy (<img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-6c816194681f741087966b0d49975a33_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"Wh\/day\" title=\"Rendered by QuickLaTeX.com\" height=\"19\" width=\"61\" style=\"vertical-align: -5px;\"\/>)<\/strong>. If you took hourly readings, the sum of the measured watts is directly the total energy at <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-75c02632c76ab1231d17c5cda0995f6c_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"Wh\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"29\" style=\"vertical-align: 0px;\"\/>.<\/li>\n<\/ol>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<p class=\"wp-block-paragraph\"><strong>Example of Sum:<\/strong> If at 10:00h you obtained <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-f2bb9969899b1295d49fae9f523f06a3_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"0.5 W\" title=\"Rendered by QuickLaTeX.com\" height=\"13\" width=\"42\" style=\"vertical-align: 0px;\"\/> and at 11:00h you obtained <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-58eb298ca92c75b02b169960e42f9a61_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"0.7 W\" title=\"Rendered by QuickLaTeX.com\" height=\"13\" width=\"42\" style=\"vertical-align: 0px;\"\/>you have accumulated <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-f7e15d86545a77d348381a2e42204e6e_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"1.2 Wh\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"51\" style=\"vertical-align: 0px;\"\/> in that two-hour period.<\/p>\n<\/blockquote>\n\n\n\n<p class=\"wp-block-paragraph\">This process will give you the <strong>real energy<\/strong> that your panel is delivering at your location and under the current climatic conditions, which is much more useful than the nominal value of <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-12cae0d6516f97a319f59aae47c1d2d5_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"1 W\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"27\" style=\"vertical-align: 0px;\"\/>.<\/p>\n\n\n<div class=\"gb-container gb-container-7f29d8b0\">\n\n<p class=\"wp-block-paragraph\">As you can see, both are tedious processes, that <strong>take a long time and require many manual steps<\/strong> where you have to go <strong>modifying parameters and making measurements and calculations<\/strong>.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">To find the MPP (<img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-82e71336aba0c7d7a113696dc9766062_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"V_{mpp}\" title=\"Rendered by QuickLaTeX.com\" height=\"18\" width=\"36\" style=\"vertical-align: -6px;\"\/> e <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-dfe25d8170c00c2f8c0029a1b7a9681a_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"I_{mpp}\" title=\"Rendered by QuickLaTeX.com\" height=\"18\" width=\"34\" style=\"vertical-align: -6px;\"\/>) you will have to do <strong>many measures in a very short space of time<\/strong>and at each one vary the load manually, or each point of your measurement will be with a different solar radiation (the sun's energy changes continuously and rapidly). <\/p>\n\n\n\n<p class=\"wp-block-paragraph\">To measure the Total Energy Generated (<img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-6c816194681f741087966b0d49975a33_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"Wh\/day\" title=\"Rendered by QuickLaTeX.com\" height=\"19\" width=\"61\" style=\"vertical-align: -5px;\"\/>), it will not be enough to measure every hour every hour, the accuracy of the measurement you get will be very low. You may have to measure every 5 minutes and this is tedious.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">This is why these measures on solar panels, although conceptually very simple, are very difficult to do in practice without <strong>an appropriate measuring instrument,<\/strong> to automate it.<\/p>\n\n<\/div>\n\n\n<h2 class=\"wp-block-heading\" id=\"h-la-electronica-invisible-cargador-solar-mppt-el-secreto-de-la-eficiencia\">Invisible Electronics: MPPT Solar Charger (The Secret of Efficiency!)<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">The rated power of the <strong>solar panel<\/strong> is irrelevant if you don't have the electronics for <strong>extract it efficiently<\/strong>. This is where the <strong>load controller<\/strong>.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"h-el-concepto-de-maxima-potencia-mpp\">The Maximum Power Concept (MPP)<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Solar panels have an ideal point of operation where the combination of voltage and current produces maximum power: the <strong><a href=\"https:\/\/es.wikipedia.org\/wiki\/Seguidor_de_punto_de_m%C3%A1xima_potencia\" target=\"_blank\" rel=\"noreferrer noopener\">Maximum Power Point (MPP)<\/a><\/strong>.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">If the charger or circuit demands too much current from the panel, the output voltage collapses (moves away from the MPP). When the voltage drops, the power delivered drops drastically, wasting much of what the panel could have delivered.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The power that your solar panel generates is directly linked to the <strong>cargo<\/strong> you connect to it. If the connected circuit draws too little current (very high resistance), the panel operates at its rated current. <strong>Open Circuit Voltage (<img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-98177521697f4f282c22deb7b6bb3ed6_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"V_{oc}\" title=\"Rendered by QuickLaTeX.com\" height=\"15\" width=\"23\" style=\"vertical-align: -3px;\"\/>)<\/strong>which is high, but the current is almost zero, so the power is low. Conversely, if the circuit demands too much current (short circuit), you will get the maximum current (<img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-c51055cb1978ebf3ca3f7cf32e9399cb_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"I_{sc}\" title=\"Rendered by QuickLaTeX.com\" height=\"15\" width=\"20\" style=\"vertical-align: -3px;\"\/>), but the voltage will be zero, and the power will return to zero.<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"960\" height=\"540\" src=\"https:\/\/emariete.com\/wp-content\/uploads\/2025\/12\/Curva-IV-Energia-Paneles-Solares.png\" alt=\"Current-voltage graph with vertical axis labelled &#039;Current [A]&#039; and horizontal axis &#039;Voltage [V]&#039;, showing a dark almost flat I-V curve falling sharply to the right and a red P-V curve rising to a peak marked by arrows as &#039;Point of maximum power&#039;, with dashed vertical and horizontal lines indicating the voltage and current at that point.\" class=\"wp-image-242865\" srcset=\"https:\/\/emariete.com\/wp-content\/uploads\/2025\/12\/Curva-IV-Energia-Paneles-Solares.png 960w, https:\/\/emariete.com\/wp-content\/uploads\/2025\/12\/Curva-IV-Energia-Paneles-Solares-300x169.png 300w, https:\/\/emariete.com\/wp-content\/uploads\/2025\/12\/Curva-IV-Energia-Paneles-Solares-768x432.png 768w\" sizes=\"auto, (max-width: 960px) 100vw, 960px\" \/><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">As you can see in the following graph where all possible combinations of voltage and current of the panel have been measured, there is only one point where the panel was generating <strong><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-8ceb29d4d222c67f65fcd99f6d6ff033_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"0.6475 W\" title=\"Rendered by QuickLaTeX.com\" height=\"13\" width=\"69\" style=\"vertical-align: 0px;\"\/><\/strong>and this is when we load the panel with <strong><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-6266d220555be52c7d19144fdb15e476_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"0.107 A\" title=\"Rendered by QuickLaTeX.com\" height=\"13\" width=\"54\" style=\"vertical-align: 0px;\"\/><\/strong> and this one delivers <strong><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-3d281d5073b16f45d8f51263684f166e_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"6,040 V\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"55\" style=\"vertical-align: 0px;\"\/><\/strong> (the red square). All other load combinations generated much less. The purple curve is the <strong>maximum energy<\/strong> that the panel can generate depending on the load it has.<\/p>\n\n\n\n<figure data-wp-context=\"{&quot;imageId&quot;:&quot;6a80994bcb35e&quot;}\" data-wp-interactive=\"core\/image\" data-wp-key=\"6a80994bcb35e\" class=\"wp-block-image alignwide size-full wp-lightbox-container\"><img loading=\"lazy\" decoding=\"async\" width=\"740\" height=\"599\" data-wp-class--hide=\"state.isContentHidden\" data-wp-class--show=\"state.isContentVisible\" data-wp-init=\"callbacks.setButtonStyles\" data-wp-on--click=\"actions.showLightbox\" data-wp-on--load=\"callbacks.setButtonStyles\" data-wp-on--pointerdown=\"actions.preloadImage\" data-wp-on--pointerenter=\"actions.preloadImageWithDelay\" data-wp-on--pointerleave=\"actions.cancelPreload\" data-wp-on-window--resize=\"callbacks.setButtonStyles\" src=\"https:\/\/emariete.com\/wp-content\/uploads\/2025\/12\/Paneles-Solares-de-Baja-Potencia-Curva-IV.jpg\" alt=\"Modal plot entitled &#039;Solar Panel I-V Curve&#039; showing the current curve (blue dotted line) almost flat up to about 6 V and then descending, the power curve dotted purple with a peak near 6 V and a MPP point highlighted in red labelled &#039;V=6.040V I=0.107A P=0.6475W&#039;, axes labelled Voltage (V), Current (A) and Power (W), and &#039;Generate I-V Curve&#039; and &#039;Close&#039; buttons in the bottom right corner.\" class=\"wp-image-242848\" srcset=\"https:\/\/emariete.com\/wp-content\/uploads\/2025\/12\/Paneles-Solares-de-Baja-Potencia-Curva-IV.jpg 740w, https:\/\/emariete.com\/wp-content\/uploads\/2025\/12\/Paneles-Solares-de-Baja-Potencia-Curva-IV-300x243.jpg 300w\" sizes=\"auto, (max-width: 740px) 100vw, 740px\" \/><button\n\t\t\tclass=\"lightbox-trigger\"\n\t\t\ttype=\"button\"\n\t\t\taria-haspopup=\"dialog\"\n\t\t\tdata-wp-bind--aria-label=\"state.thisImage.triggerButtonAriaLabel\"\n\t\t\tdata-wp-init=\"callbacks.initTriggerButton\"\n\t\t\tdata-wp-on--click=\"actions.showLightbox\"\n\t\t\tdata-wp-style--right=\"state.thisImage.buttonRight\"\n\t\t\tdata-wp-style--top=\"state.thisImage.buttonTop\"\n\t\t>\n\t\t\t<svg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"12\" height=\"12\" fill=\"none\" viewbox=\"0 0 12 12\">\n\t\t\t\t<path fill=\"#fff\" d=\"M2 0a2 2 0 0 0-2 2v2h1.5V2a.5.5 0 0 1 .5-.5h2V0H2Zm2 10.5H2a.5.5 0 0 1-.5-.5V8H0v2a2 2 0 0 0 2 2h2v-1.5ZM8 12v-1.5h2a.5.5 0 0 0 .5-.5V8H12v2a2 2 0 0 1-2 2H8Zm2-12a2 2 0 0 1 2 2v2h-1.5V2a.5.5 0 0 0-.5-.5H8V0h2Z\" \/>\n\t\t\t<\/svg>\n\t\t<\/button><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">Between these two extremes, there is a single ideal point where the power curve (W) reaches its maximum peak: the <strong>MPP<\/strong>. The purpose of the charge controller <strong>MPPT<\/strong> is precisely to manipulate the panel load (the input impedance of the charger) so that the panel voltage is maintained. <strong>exactly at that optimum point (<img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-82e71336aba0c7d7a113696dc9766062_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"V_{mpp}\" title=\"Rendered by QuickLaTeX.com\" height=\"18\" width=\"36\" style=\"vertical-align: -6px;\"\/>)<\/strong>This ensures that you get the maximum power possible in all lighting conditions. If you can get the panel to operate at this voltage, you will get the maximum possible power in any light condition. <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-82e71336aba0c7d7a113696dc9766062_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"V_{mpp}\" title=\"Rendered by QuickLaTeX.com\" height=\"18\" width=\"36\" style=\"vertical-align: -6px;\"\/>the resulting power will be the highest power that the panel can deliver at that time.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"h-la-sinergia-cargador-solar-especializado\">The Synergy: Specialised Solar Charger<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">Not every charger is suitable for every <strong>solar panel<\/strong>. It is <strong>ABSOLUTELY CRITICAL<\/strong> to use a <strong>solar charger<\/strong> designed <strong>specifically<\/strong> to operate with <strong>solar panels<\/strong>not just a USB charger.<\/p>\n\n\n\n<figure class=\"wp-block-table\"><table class=\"has-fixed-layout\"><thead><tr><td><strong>Type of charger<\/strong><\/td><td><strong>Main Design<\/strong><\/td><td><strong>Why is it CRITICAL with solar panels?<\/strong><\/td><\/tr><\/thead><tbody><tr><td><strong>MPPT (Maximum Power Point Tracking)<\/strong><\/td><td>It uses algorithms to search for the MPP.<\/td><td><strong>Essential:<\/strong> Maximizes efficiency (up to <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-2bb3d409936612dafc5318ffc78487d2_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"&#51;&#48;&#92;&#37;\" title=\"Rendered by QuickLaTeX.com\" height=\"15\" width=\"32\" style=\"vertical-align: -1px;\"\/> more than others) by ensuring that the panel is always working at its best power point, crucial when light is scarce and you have <strong>low-power solar panels<\/strong>.<\/td><\/tr><tr><td><strong>Linear Chips (e.g. TP4056)<\/strong><\/td><td>Designed for fixed voltage input (typically 5V USB).<\/td><td><strong>Inadequate:<\/strong> They do not have the intelligence to search for the MPP, forcing the panel to a suboptimal voltage and <strong>wasting most of the power<\/strong> you need.<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">If you are already struggling with a <strong>low-power solar panel<\/strong>you need a smart charger <strong>MPPT<\/strong> (such as chip-based <strong>CN3971<\/strong> o <strong>MCP73871<\/strong>) to ensure that scarce power is used to its full potential.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"h-el-ejemplo-maestro-las-luces-led-solares-de-exterior-simplicidad-inteligente\">The Master Example: Solar LED Outdoor Lights (Smart Simplicity)<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">So, if efficiency is so critical, why do those cheap LED garden lights work so well with <strong>solar panels<\/strong> tiny?<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The key is that its design is not based on raw power, but rather on the <strong>ingenious simplicity<\/strong>:<\/p>\n\n\n\n<ol start=\"1\" class=\"wp-block-list\">\n<li><strong>Fixed and Minimum Consumption:<\/strong> They do not use Wi-Fi or peak consumption. They have <strong>zero consumption during the day<\/strong> (while charging) and constant\/fixed consumption of <strong>just a few milliamps overnight only<\/strong>This greatly simplifies energy management.<\/li>\n\n\n\n<li><strong>The Charge Doesn't Need to be Perfect:<\/strong> They use a very simple linear charging circuit. Because the power consumption is so low, even if the charging system is inefficient (it does not operate at MPP), the panel generates enough energy to compensate for that loss during the day.<\/li>\n\n\n\n<li><strong>The Panel as a Sensor:<\/strong> The panel not only charges, but also detects light. When the panel stops producing voltage at dusk, it activates the switch that turns on the LED.<\/li>\n<\/ol>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Lesson:<\/strong> The basic solution works only for basic and minimalistic needs. Your project (with connectivity) is simply not a basic need and therefore cannot afford the luxury of inefficiency.<\/p>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"h-ejemplo-practico-dimensionamiento-y-la-crueldad-del-deep-sleep\">Practical Example: Dimensioning and the Cruelty of the <em>Deep Sleep<\/em><\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">Let's see why the belief that <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-12cae0d6516f97a319f59aae47c1d2d5_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"1 W\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"27\" style=\"vertical-align: 0px;\"\/> is sufficient for many projects with <strong>ESP32<\/strong> is misleading. <strong>Consumption rules over generation.<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Scenario:<\/strong> Thermometer with ESP32 connected to a battery charged by an ESP32 panel. <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-12cae0d6516f97a319f59aae47c1d2d5_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"1 W\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"27\" style=\"vertical-align: 0px;\"\/>.<\/p>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"h-opcion-a-proyecto-optimizado-usando-deep-sleep\">Option A: Optimised Project (Using <em>Deep Sleep<\/em>)<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Behaviour:<\/strong> ESP32 wakes up <strong>every 5 minutes<\/strong>reads a sensor, connects to Wi-Fi (high overhead), sends data and then returns to <strong>Deep Sleep<\/strong> (minimum expenditure).<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Maintenance and Autonomy Calculation:<\/strong> The daily consumption to maintain the system (including losses and margin) is approx. <strong><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-0774af4d8a7bed5c6d6952c1f6158fa9_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"0.4 Wh\/day\" title=\"Rendered by QuickLaTeX.com\" height=\"19\" width=\"84\" style=\"vertical-align: -5px;\"\/><\/strong> (this value is calculated assuming a consumption of <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-cb4efa7c7865cdd76ee9a4f406a0fc98_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"\u2248 100 \u00b5A\" title=\"Rendered by QuickLaTeX.com\" height=\"17\" width=\"70\" style=\"vertical-align: -4px;\"\/> at <em>Deep Sleep<\/em> and a peak of <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-fb4c64cad98da63365e638126e68d8d2_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"approx. 150 mA\" title=\"Rendered by QuickLaTeX.com\" height=\"13\" width=\"75\" style=\"vertical-align: 0px;\"\/> for 3 seconds per Wi-Fi connection).<\/li>\n\n\n\n<li>Minimum Panel Power: Let's use the lowest Peak Sun Hours (PSH) in winter (Madrid): <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-1d55561a2313ec508c3a1b890c1672f4_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"\\mathbf{2.5 HSP}\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"64\" style=\"vertical-align: 0px;\"\/>.<p class=\"ql-center-displayed-equation\" style=\"line-height: 36px;\"><span class=\"ql-right-eqno\"> &nbsp; <\/span><span class=\"ql-left-eqno\"> &nbsp; <\/span><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-488c1f18675b4eefc1b4465d9703860f_l3.png\" height=\"36\" width=\"304\" class=\"ql-img-displayed-equation quicklatex-auto-format\" alt=\"\\[\\[\\text{Minimum Power} = \\mathbf{0.4\\Wh} = \\mathbf{0.16\\W}].\" title=\"Rendered by QuickLaTeX.com\"\/><\/p><\/li>\n\n\n\n<li><strong>Conclusion:<\/strong> Your panel of <strong><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-12cae0d6516f97a319f59aae47c1d2d5_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"1 W\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"27\" style=\"vertical-align: 0px;\"\/><\/strong> (which produces <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-81092876f214d93814e18fa7d597b5ae_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"2.5 Wh\/day\" title=\"Rendered by QuickLaTeX.com\" height=\"19\" width=\"84\" style=\"vertical-align: -5px;\"\/>) is <strong>sufficient<\/strong> and even oversized, <em>as long as you use Deep Sleep<\/em>. The problem here is the <strong>load efficiency<\/strong> (you need MPPT).<\/li>\n<\/ul>\n\n\n\n<h3 class=\"wp-block-heading\" id=\"h-opcion-b-proyecto-sin-optimizar-sin-deep-sleep\">Option B: Unoptimised Project (No <em>Deep Sleep<\/em>)<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Behaviour:<\/strong> ESP32 is maintained <strong>constantly connected<\/strong> and active (as if you were doing <em>streaming<\/em> data 24\/7).<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Daily Consumption Requirement:<\/strong> <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-ce7ea4c354c83d6d45f164c3777d6bf3_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"\\approx \\mathbf{10.6 Wh\/day}\" title=\"Rendered by QuickLaTeX.com\" height=\"19\" width=\"122\" style=\"vertical-align: -5px;\"\/>.<\/li>\n\n\n\n<li><strong>Power produced by your panel <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-12cae0d6516f97a319f59aae47c1d2d5_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"1 W\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"27\" style=\"vertical-align: 0px;\"\/>:<\/strong> <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-3ce17ea14c46bcbf1569c01d879b5aae_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"\\mathbf{2.5 Wh\/day}\" title=\"Rendered by QuickLaTeX.com\" height=\"19\" width=\"92\" style=\"vertical-align: -5px;\"\/> (in winter).<\/li>\n\n\n\n<li><strong>Conclusion:<\/strong> The panel only generates the <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-b0968792bb84d76b14407442619d60c6_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"\\mathbf{23\\%}\" title=\"Rendered by QuickLaTeX.com\" height=\"15\" width=\"33\" style=\"vertical-align: -1px;\"\/> of the energy the system needs. The battery will die within a day. <strong>No matter how good your MPPT charger is, the power just isn't there!<\/strong><\/li>\n<\/ul>\n\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\">\n<p class=\"wp-block-paragraph\"><strong>The Lesson:<\/strong> The difference between <strong><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-7399c32c6586fb47517e343bc1b9b614_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"0.4 Wh\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"52\" style=\"vertical-align: 0px;\"\/><\/strong> y <strong><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-52d8d3721c0db6ec5753e1c86fdd6f1f_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"10.6 Wh\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"60\" style=\"vertical-align: 0px;\"\/><\/strong> is what condemns your project. It is <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-228917250a059d52aec5737c497a3870_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"\\mathbf{26 times}}\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"65\" style=\"vertical-align: 0px;\"\/> more efficient to optimise the code (Deep Sleep) than to try to optimise the generation (MPPT), although both are necessary.<\/p>\n<\/blockquote>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"h-las-expectativas-reales-horas-de-sol-pico-hsp\">Real Expectations: Hours of Peak Sunshine (HSP)<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">When sizing a solar system, we ignore the hours of visible sunlight and focus on the hours of visible sunlight. <strong><a href=\"https:\/\/es.wikipedia.org\/wiki\/Hora_solar_pico\" target=\"_blank\" rel=\"noreferrer noopener\">Hours of Peak Sunshine (HSP)<\/a><\/strong>. An HSP is an hour of sunshine with an ideal irradiance (<img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-9847057d4733795589e2c8d2c2690a98_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"1000 W\/m\u00b2\" title=\"Rendered by QuickLaTeX.com\" height=\"20\" width=\"84\" style=\"vertical-align: -5px;\"\/>).<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Attention, Key Concept!<\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">When we say that \"In the summer, HSPs can be <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-435c9fab9b23bb690c6da2a818c8c8b4_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"approx. 5\u20136\" title=\"Rendered by QuickLaTeX.com\" height=\"13\" width=\"58\" style=\"vertical-align: 0px;\"\/> hours\/day\" does not mean that the panel is producing its maximum output of <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-12cae0d6516f97a319f59aae47c1d2d5_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"1 W\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"27\" style=\"vertical-align: 0px;\"\/> during those 5 or 6 hours.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">HSPs are a value <strong>equivalent<\/strong> y <strong>averaged<\/strong>. That is, the total amount of energy you receive during the many hours of sunshine (from sunrise to sunset, where the intensity varies from <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-d7534c06db2683dba17997cee53d65b1_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"0 W\/m\u00b2\" title=\"Rendered by QuickLaTeX.com\" height=\"20\" width=\"58\" style=\"vertical-align: -5px;\"\/> a <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-9847057d4733795589e2c8d2c2690a98_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"1000 W\/m\u00b2\" title=\"Rendered by QuickLaTeX.com\" height=\"20\" width=\"84\" style=\"vertical-align: -5px;\"\/> and vice versa), is the same as if your panel had been generating a <strong>maximum power (<img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-12cae0d6516f97a319f59aae47c1d2d5_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"1 W\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"27\" style=\"vertical-align: 0px;\"\/>) for only 5 or 6 hours<\/strong> of the day.<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>In summer, HSPs can be <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-435c9fab9b23bb690c6da2a818c8c8b4_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"approx. 5\u20136\" title=\"Rendered by QuickLaTeX.com\" height=\"13\" width=\"58\" style=\"vertical-align: 0px;\"\/> hours\/day.<\/li>\n\n\n\n<li>In winter, HSPs can fall to <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-b63aeabd0f0d925aa675cc627c00c60f_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"approx. 2\u20133\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"58\" style=\"vertical-align: 0px;\"\/> hours\/day.<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>Medium Power is Low!<\/strong> A panel of <strong><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-12cae0d6516f97a319f59aae47c1d2d5_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"1 W\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"27\" style=\"vertical-align: 0px;\"\/><\/strong> only produces <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-8c267d62c3d7048247917e13baec69a5_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"&#50;\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"8\" style=\"vertical-align: 0px;\"\/> a <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-47a08710cca895e45fd4cf58ea387f55_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"3 Wh\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"38\" style=\"vertical-align: 0px;\"\/> per day in winter (based on <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-c8bfead746314bbab24809331cbe5979_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"&#50;&#45;&#51;\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"40\" style=\"vertical-align: 0px;\"\/> HSP). If your project is more complex, this low production is the main reason for the failures.<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><img loading=\"lazy\" decoding=\"async\" width=\"711\" height=\"380\" src=\"https:\/\/emariete.com\/wp-content\/uploads\/2025\/12\/image.png\" alt=\"Graph with a blue bell-shaped curve showing irradiance throughout the day, with a yellow rectangle centred around noon highlighting peak solar hours and a double black arrow indicating its width; axes labelled &#039;Irradiance [W\/m\u00b2]&#039; (vertical) and &#039;Time of day&#039; (horizontal).\" class=\"wp-image-242851\" srcset=\"https:\/\/emariete.com\/wp-content\/uploads\/2025\/12\/image.png 711w, https:\/\/emariete.com\/wp-content\/uploads\/2025\/12\/image-300x160.png 300w\" sizes=\"auto, (max-width: 711px) 100vw, 711px\" \/><figcaption class=\"wp-element-caption\">Source: Wikipedia <\/figcaption><\/figure>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"h-errores-comunes-por-ignorancia-y-por-que-fallan\">Common Ignorance Mistakes (And Why They Fail)<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">The pursuit of simplicity leads to disastrous failures in projects that use <strong>low-power solar panels<\/strong>:<\/p>\n\n\n\n<ol start=\"1\" class=\"wp-block-list\">\n<li><strong>Direct Connection (\"Peeled Panel\"):<\/strong> Attempt to connect a panel directly to a battery or circuit.\n<ul class=\"wp-block-list\">\n<li><strong>Failure:<\/strong> The panel <strong>does not operate in its PPM<\/strong>The battery is then damaged by overcharging or over-discharging, producing a tiny fraction of its capacity. A panel of <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-4b15e4ee5da72b90f3151157cde723fe_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"\\mathbf{6 V}\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"25\" style=\"vertical-align: 0px;\"\/> connected to a Li-ion battery of <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-e8c428cee9f795dfa81807d1d0257d33_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"\\mathbf{4.2 V}\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"40\" style=\"vertical-align: 0px;\"\/> can overload it and <strong>cause serious damage or even fire<\/strong>. <strong>The charger is not just efficiency, it's safety!<\/strong><\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>The Mismatched Charger:<\/strong> Use a simple charger designed for USB (5V fixed) with a higher voltage solar panel (9V or 12V).\n<ul class=\"wp-block-list\">\n<li><strong>Failure:<\/strong> The panel is forced to a voltage that is not its MPP, and the efficiency is drastically reduced, making the project unfeasible.<\/li>\n<\/ul>\n<\/li>\n\n\n\n<li><strong>Omission of the Blocking Diode:<\/strong> Do not use a diode (or a charger that integrates a diode) to prevent the energy from the <strong>battery is discharged back into the panel<\/strong> when it gets dark.\n<ul class=\"wp-block-list\">\n<li><strong>Failure:<\/strong> The little energy you charged during the day is lost at night.<\/li>\n<\/ul>\n<\/li>\n<\/ol>\n\n\n\n<h2 class=\"wp-block-heading\" id=\"h-conclusion-sobredimensionar-tu-panel-solar-y-usar-mptt-es-la-solucion\">Conclusion: Oversizing your Solar Panel and using MPTT is the Solution<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">The final lesson is clear: if you use <strong>low-power solar panels<\/strong>you need <strong>smart electronics<\/strong> in electronics and <strong>margin for error<\/strong>.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">For the <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-702ee7d4809a367d93c3a93c9a75442b_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"&#57;&#48;&#92;&#37;\" title=\"Rendered by QuickLaTeX.com\" height=\"15\" width=\"32\" style=\"vertical-align: -1px;\"\/> amateurs, to invest a little more in a <strong>solar panel<\/strong> is the best solution to avoid headaches. Switching from <strong><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-12cae0d6516f97a319f59aae47c1d2d5_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"1 W\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"27\" style=\"vertical-align: 0px;\"\/><\/strong> a <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-6f3e1490d96d2cbbd12feb4ac150f431_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"5 W\" title=\"Rendered by QuickLaTeX.com\" height=\"13\" width=\"28\" style=\"vertical-align: 0px;\"\/> o <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-6b89e5410ed71e05c1fa3a9254703711_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"10 W\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"36\" style=\"vertical-align: 0px;\"\/> not only provides more energy, but also guarantees:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>System stability<\/strong> (higher margin at peak consumption).<\/li>\n\n\n\n<li><strong>Increased load efficiency<\/strong> (allows the MPPT to work better).<\/li>\n\n\n\n<li><strong>Battery longevity<\/strong> (avoid deep discharges in winter).<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph translation-block\">Don't get caught up in the cheap price tag. An <strong>undersized solar panel<\/strong>, no matter how good the rest of your electronics are, will condemn you to an unstable or inoperative project.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">It is very important, where possible, to design hardware and firmware with energy efficiency in mind, as you can see in the following post.<\/p>\n\n\n<div class=\"gb-container gb-container-a1077fd2\">\n\n<figure class=\"wp-block-embed aligncenter is-type-wp-embed is-provider-emariete wp-block-embed-emariete\"><div class=\"wp-block-embed__wrapper\">\n<blockquote class=\"wp-embedded-content\" data-secret=\"bbcAT6m5gN\"><a href=\"https:\/\/emariete.com\/en\/design-co2-meter-ultra-ultra-low-consumption\/\">Design of an ultra-low consumption CO2 meter<\/a><\/blockquote><iframe loading=\"lazy\" class=\"wp-embedded-content\" sandbox=\"allow-scripts\" security=\"restricted\" style=\"position: absolute; visibility: hidden;\" title=\"&quot;Design of an ultra-low power CO2 meter&quot; - eMariete\" src=\"https:\/\/emariete.com\/diseno-medidor-co2-ultra-bajo-consumo\/embed\/#?secret=5FOzAwhj1O#?secret=bbcAT6m5gN\" data-secret=\"bbcAT6m5gN\" width=\"600\" height=\"338\" frameborder=\"0\" marginwidth=\"0\" marginheight=\"0\" scrolling=\"no\"><\/iframe>\n<\/div><\/figure>\n\n<\/div>\n\n\n<h2 class=\"wp-block-heading\" id=\"h-y-ahora-que\">And now what?<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">We have established one fundamental truth: the success of your projects with <strong>low-power solar panels<\/strong> is not only about generation (MPPT), but also about consumption optimisation (<strong>on <em>hardware<\/em> y <em>software<\/em> of your project<\/strong>). You already know that your <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-12cae0d6516f97a319f59aae47c1d2d5_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"1 W\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"27\" style=\"vertical-align: 0px;\"\/> only produces a fraction of what is nominal, and that it is easier to reduce demand than to increase supply.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">But the work does not stop here. The key to long-term success is the <strong>measurement and characterisation<\/strong> of your components.<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>Next Step: Advanced DIY Test and Measurement Instrumentation<\/strong><\/li>\n<\/ul>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"576\" src=\"https:\/\/emariete.com\/wp-content\/uploads\/2025\/12\/EnerLogik-Featured-Image-1024x576.png\" alt=\"Protoboard with various electronic modules and cables, including a battery holder with two cylindrical batteries highlighted in red, on a table with a laptop in the background and large text that reads &quot;SOLAR ENERGY FOR MICROCONTROLLERS! GENERLOGIK!&quot;\" class=\"wp-image-242828\" srcset=\"https:\/\/emariete.com\/wp-content\/uploads\/2025\/12\/EnerLogik-Featured-Image-1024x576.png 1024w, https:\/\/emariete.com\/wp-content\/uploads\/2025\/12\/EnerLogik-Featured-Image-300x169.png 300w, https:\/\/emariete.com\/wp-content\/uploads\/2025\/12\/EnerLogik-Featured-Image-768x432.png 768w, https:\/\/emariete.com\/wp-content\/uploads\/2025\/12\/EnerLogik-Featured-Image-1536x864.png 1536w, https:\/\/emariete.com\/wp-content\/uploads\/2025\/12\/EnerLogik-Featured-Image.png 1920w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">To stop relying on assumptions and start measuring real energy, I will soon publish a cool project of a <strong>advanced DIY test and measurement instrument<\/strong>the Enerogik. This instrument is used to characterise:<\/p>\n\n\n\n<ul start=\"1\" class=\"wp-block-list\">\n<li><strong>Solar Panels:<\/strong> Get your actual curve <img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/emariete.com\/wp-content\/ql-cache\/quicklatex.com-b340ebfb4f33ec18e25c343c31b4da05_l3.png\" class=\"ql-img-inline-formula quicklatex-auto-format\" alt=\"I-V\" title=\"Rendered by QuickLaTeX.com\" height=\"12\" width=\"45\" style=\"vertical-align: 0px;\"\/> to find the exact MPP.<\/li>\n\n\n\n<li><strong>Batteries:<\/strong> Know their capacity and status.<\/li>\n\n\n\n<li><strong>Chargers and Feeders:<\/strong> Evaluate their efficiency and performance in a way that <strong>easy, precise and automatic<\/strong>.<\/li>\n<\/ul>\n\n\n\n<figure data-wp-context=\"{&quot;imageId&quot;:&quot;6a80994bce467&quot;}\" data-wp-interactive=\"core\/image\" data-wp-key=\"6a80994bce467\" class=\"wp-block-image size-large wp-lightbox-container\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"905\" data-wp-class--hide=\"state.isContentHidden\" data-wp-class--show=\"state.isContentVisible\" data-wp-init=\"callbacks.setButtonStyles\" data-wp-on--click=\"actions.showLightbox\" data-wp-on--load=\"callbacks.setButtonStyles\" data-wp-on--pointerdown=\"actions.preloadImage\" data-wp-on--pointerenter=\"actions.preloadImageWithDelay\" data-wp-on--pointerleave=\"actions.cancelPreload\" data-wp-on-window--resize=\"callbacks.setButtonStyles\" src=\"https:\/\/emariete.com\/wp-content\/uploads\/2025\/12\/EnerLogik-WEB-preview-1024x905.jpg\" alt=\"EnerLogik&quot; energy control panel with three top boards (Charge, Battery and Solar Panel) showing voltage, current and power; MCP4725 control section with a slider, voltage and percentage fields and Apply buttons; and a &quot;Live Measurements&quot; graph at the bottom with various voltage, current and power lines.\" class=\"wp-image-242859\" srcset=\"https:\/\/emariete.com\/wp-content\/uploads\/2025\/12\/EnerLogik-WEB-preview-1024x905.jpg 1024w, https:\/\/emariete.com\/wp-content\/uploads\/2025\/12\/EnerLogik-WEB-preview-300x265.jpg 300w, https:\/\/emariete.com\/wp-content\/uploads\/2025\/12\/EnerLogik-WEB-preview-768x679.jpg 768w, https:\/\/emariete.com\/wp-content\/uploads\/2025\/12\/EnerLogik-WEB-preview.jpg 1065w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><button\n\t\t\tclass=\"lightbox-trigger\"\n\t\t\ttype=\"button\"\n\t\t\taria-haspopup=\"dialog\"\n\t\t\tdata-wp-bind--aria-label=\"state.thisImage.triggerButtonAriaLabel\"\n\t\t\tdata-wp-init=\"callbacks.initTriggerButton\"\n\t\t\tdata-wp-on--click=\"actions.showLightbox\"\n\t\t\tdata-wp-style--right=\"state.thisImage.buttonRight\"\n\t\t\tdata-wp-style--top=\"state.thisImage.buttonTop\"\n\t\t>\n\t\t\t<svg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"12\" height=\"12\" fill=\"none\" viewbox=\"0 0 12 12\">\n\t\t\t\t<path fill=\"#fff\" d=\"M2 0a2 2 0 0 0-2 2v2h1.5V2a.5.5 0 0 1 .5-.5h2V0H2Zm2 10.5H2a.5.5 0 0 1-.5-.5V8H0v2a2 2 0 0 0 2 2h2v-1.5ZM8 12v-1.5h2a.5.5 0 0 0 .5-.5V8H12v2a2 2 0 0 1-2 2H8Zm2-12a2 2 0 0 1 2 2v2h-1.5V2a.5.5 0 0 0-.5-.5H8V0h2Z\" \/>\n\t\t\t<\/svg>\n\t\t<\/button><\/figure>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>The Critical Hardware: Specific Solar Chargers<\/strong><\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Finally, since we have already stressed that the choice of charger is ABSOLUTELY CRITICAL, we will soon provide you with a comprehensive guide to <strong>solar chargers for small panels<\/strong>. We will analyse in detail:<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Specific boards with MPPT chips such as CN3971 and MCP73871.<\/li>\n\n\n\n<li>Analysis of the most common plaques (including those to avoid).<\/li>\n\n\n\n<li>Tips for connection and configuration of the load.<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">Subscribe to our notifications channel so that you don't miss the construction of the measuring instrument and the guide for <em>hardware<\/em> your project needs!<\/p>\n<div class=\"essb_break_scroll\"><\/div>","protected":false},"excerpt":{"rendered":"<p>We\u2019ve seen lots of brilliant DIY projects using solar panels, but the reality is that energy efficiency is a real challenge. If you\u2019ve tried to power an ESP32 or a Raspberry Pi with a small solar panel and failed, you\u2019re not alone. This post complements our project on Enerlogic \u2014 Energy Wizard and \u2026 <a title=\"Low-Power Solar Panels: MPPT is the Secret to Running Your ESP32 on Just 1W\" class=\"read-more\" href=\"https:\/\/emariete.com\/en\/problemas-paneles-solares-baja-potencia-esp32\/\" aria-label=\"Read more about Low Power Solar Panels: The Secret to running your ESP32 on just 1W is called MPPT\">Read more<\/a><\/p>","protected":false},"author":1,"featured_media":242844,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_uag_custom_page_level_css":"","_lmt_disableupdate":"no","_lmt_disable":"","footnotes":""},"categories":[64,70,17],"tags":[21,27,43],"class_list":["post-242832","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-electronica","category-energia-solar","category-proyectos-arduino","tag-bajo-consumo","tag-esp32","tag-proyectos-arduino"],"modified_by":"Mariete","uagb_featured_image_src":{"full":["https:\/\/emariete.com\/wp-content\/uploads\/2025\/12\/Paneles-Solares-de-Baja-Potencia-Featured-Image.png",2160,1215,false],"thumbnail":["https:\/\/emariete.com\/wp-content\/uploads\/2025\/12\/Paneles-Solares-de-Baja-Potencia-Featured-Image-150x150.png",150,150,true],"medium":["https:\/\/emariete.com\/wp-content\/uploads\/2025\/12\/Paneles-Solares-de-Baja-Potencia-Featured-Image-300x169.png",300,169,true],"medium_large":["https:\/\/emariete.com\/wp-content\/uploads\/2025\/12\/Paneles-Solares-de-Baja-Potencia-Featured-Image-768x432.png",768,432,true],"large":["https:\/\/emariete.com\/wp-content\/uploads\/2025\/12\/Paneles-Solares-de-Baja-Potencia-Featured-Image-1024x576.png",1024,576,true],"1536x1536":["https:\/\/emariete.com\/wp-content\/uploads\/2025\/12\/Paneles-Solares-de-Baja-Potencia-Featured-Image-1536x864.png",1536,864,true],"2048x2048":["https:\/\/emariete.com\/wp-content\/uploads\/2025\/12\/Paneles-Solares-de-Baja-Potencia-Featured-Image-2048x1152.png",2048,1152,true],"trp-custom-language-flag":["https:\/\/emariete.com\/wp-content\/uploads\/2025\/12\/Paneles-Solares-de-Baja-Potencia-Featured-Image.png",18,10,false]},"uagb_author_info":{"display_name":"Mariete","author_link":"https:\/\/emariete.com\/en\/author\/admin_xlyz052h\/"},"uagb_comment_info":0,"uagb_excerpt":"Hemos visto muchos proyectos caseros geniales con paneles solares, pero la realidad es que la eficiencia energ\u00e9tica es un campo de batalla. Si has intentado alimentar un ESP32 o un Raspberry Pi con un panel solar peque\u00f1o de y has fracasado, no est\u00e1s solo. Este post complementa nuestro proyecto sobre Enerlogic \u2014 Energy Wizard y&hellip;","_links":{"self":[{"href":"https:\/\/emariete.com\/en\/wp-json\/wp\/v2\/posts\/242832","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/emariete.com\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/emariete.com\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/emariete.com\/en\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/emariete.com\/en\/wp-json\/wp\/v2\/comments?post=242832"}],"version-history":[{"count":32,"href":"https:\/\/emariete.com\/en\/wp-json\/wp\/v2\/posts\/242832\/revisions"}],"predecessor-version":[{"id":242951,"href":"https:\/\/emariete.com\/en\/wp-json\/wp\/v2\/posts\/242832\/revisions\/242951"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/emariete.com\/en\/wp-json\/wp\/v2\/media\/242844"}],"wp:attachment":[{"href":"https:\/\/emariete.com\/en\/wp-json\/wp\/v2\/media?parent=242832"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/emariete.com\/en\/wp-json\/wp\/v2\/categories?post=242832"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/emariete.com\/en\/wp-json\/wp\/v2\/tags?post=242832"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}