{"id":243031,"date":"2026-06-22T15:02:15","date_gmt":"2026-06-22T13:02:15","guid":{"rendered":"https:\/\/emariete.com\/co2-gadget-guia-low-power\/"},"modified":"2026-07-07T09:10:40","modified_gmt":"2026-07-07T07:10:40","slug":"co2-gadget-guide-low-power","status":"publish","type":"post","link":"https:\/\/emariete.com\/en\/co2-gadget-guia-low-power\/","title":{"rendered":"Guide to Low-CO2 Gadgets: Deep Sleep and Battery Life"},"content":{"rendered":"<p class=\"wp-block-paragraph\">CO2 Gadget features a low-power binary system (HIGH_PERFORMANCE \/ LOW_POWER) that achieves a battery life of up to 3 months with a single 18650 battery, compared to the few hours offered by a conventional meter. Here you\u2019ll see how to configure wake-up via CO\u2082, via timer, via button, and non-blocking deep sleep techniques for SCD4x and CM1106.<\/p>\n\n\n\n\n\n\n<div style=\"background:#fff8dc;border:1px solid #e6c300;border-radius:8px;padding:12px 16px;margin:12px 0;font-size:14px;line-height:1.5;color:#333\">\n<strong>Documentation is currently being updated.<\/strong> We are currently reviewing and improving all our pages. You may come across a broken link or some content that hasn\u2019t been finalised yet. If you spot anything that isn\u2019t quite right, please help us fix it at <a href=\"https:\/\/github.com\/melkati\/CO2-Gadget\/issues\" style=\"color:#0066cc\">GitHub<\/a>.\n<\/div>\n\n\n\n\n\n<hr class=\"wp-block-separator\"\/>\n\n\n<h2 class=\"wp-block-heading\">Operating modes (binary, from v0.16.x)<\/h2>\n\n\n<p class=\"wp-block-paragraph\">From v0.16.015-beta onwards, CO2 Gadget uses a model <strong>binary<\/strong> modes (there used to be 4 modes, which have now been simplified). The preference <code>lowPowerMode<\/code> Take the values:<\/p>\n\n\n<figure class=\"wp-block-table\"><table><thead><tr><th>Mode<\/th><th>Value<\/th><th>Description<\/th><th>Consumption<\/th><\/tr><\/thead><tbody><tr><td><strong>HIGH_PERFORMANCE<\/strong><\/td><td>`0`<\/td><td>Continuous operation, no standby mode, all radios active<\/td><td>High<\/td><\/tr><tr><td><strong>LOW_POWER<\/strong><\/td><td>`1`<\/td><td>Deep sleep with configurable periodic wake-ups<\/td><td>Very low<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n<blockquote class=\"wp-block-quote is-layout-flow wp-block-quote-is-layout-flow\"><p>If you upgrade from a version earlier than v0.16, the old `MEDIUM_LOWPOWER` setting is automatically migrated to `LOW_POWER=1` via `upgradePreferences()` on the first boot.<\/p><\/blockquote>\n\n\n<h2 class=\"wp-block-heading\">Deep sleep cycle<\/h2>\n\n\n<p class=\"wp-block-paragraph\">In LOW_POWER mode, the meter wakes up periodically, takes measurements, publishes data (if applicable) and goes back to sleep. The main parameters are:<\/p>\n\n\n<figure class=\"wp-block-table\"><table><thead><tr><th>Parameter<\/th><th>Constant<\/th><th>Default<\/th><th>Meaning<\/th><\/tr><\/thead><tbody><tr><td>`waitToDeep`<\/td><td>`timeToWaitForCaptivePortal`<\/td><td>60 s<\/td><td>Time spent awake before going back to sleep<\/td><\/tr><tr><td>`timeSleeping`<\/td><td>`DEEP_SLEEP_SECONDS_DEFAULT`<\/td><td>60 s<\/td><td>Duration of deep sleep<\/td><\/tr><tr><td>Sleep range<\/td><td>`DEEP_SLEEP_SECONDS_MIN\/MAX`<\/td><td>15\u2013900 s<\/td><td>Configurable minimum and maximum limits<\/td><\/tr><tr><td>`activateWiFiEvery`<\/td><td>`cyclsWifiConn`<\/td><td>5<\/td><td>Wake cycles between Wi-Fi connections<\/td><\/tr><tr><td>`cycRedrawDis`<\/td><td>\u2014<\/td><td>5<\/td><td>Intervals between screen refreshes<\/td><\/tr><tr><td>`wakeOnCO2Alert`<\/td><td>\u2014<\/td><td>`true`<\/td><td>The screen lights up when the orange threshold is exceeded<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n<h2 class=\"wp-block-heading\">Sensor behaviour in low-power mode (v0.16.x)<\/h2>\n\n\n<p class=\"wp-block-paragraph\">Each sensor has a handler optimised to minimise power consumption whilst in wake mode:<\/p>\n\n\n<ul class=\"wp-block-list\">\n<li><strong>SCD41<\/strong> \u2014 non-blocking single-shot (`measureSingleShot(true)`), conversion within 5 seconds of light sleep. The result is processed during the next wake. This is the key improvement in v0.16.015.<\/li>\n<li><strong>SCD40<\/strong> \u2014 `startLowPowerPeriodicMeasurement()`, wait time limited to 31 s in a 0.3 s light sleep.<\/li>\n<li><strong>SCD30<\/strong> \u2014 continuous mode, wait time limited to `(sampleTime + 1) \u00d7 1000` ms.<\/li>\n<li><strong>CM1106SL-NS<\/strong> \u2014 wait for RDY to be active-LOW for up to 2 s, cycle from HIGH to LOW, validation `CO\u2082 &gt; 0`.<\/li>\n<li><strong>MH-Z19 \/ Senseair S8<\/strong> \u2014 standard continuous reading.<\/li>\n<\/ul>\n\n\n<h2 class=\"wp-block-heading\">BTHome in low-power mode<\/h2>\n\n\n<p class=\"wp-block-paragraph\">When the BLE BTHome is active (<code>SUPPORT<em>BTHOME<\/em>BLE<\/code>), whilst in deep sleep mode, the meter emits a brief BTHome announcement (<code>BLE<em>WAKE<\/em>ADVERTISEMENT<em>MS = 2500 ms<\/code>) before going back to sleep. <strong>PM particle sensors are omitted<\/strong> in the display (the fan does not allow time for a valid measurement); the selection is held and resumes automatically when the setting returns to HIGH<\/em>PERFORMANCE.<\/p>\n\n\n<h2 class=\"wp-block-heading\">Barometric pressure in the wake<\/h2>\n\n\n<p class=\"wp-block-paragraph\">If your build includes <code>SUPPORT<em>LOW<\/em>POWER_PRESSURE<\/code> and a BME280 sensor; at each wake, a <code>takeForcedMeasurement()<\/code> to get an up-to-date pressure reading without exiting sleep mode. This pressure is published via BTHome and MQTT.<\/p>\n\n\n<h2 class=\"wp-block-heading\">Web-based configuration<\/h2>\n\n\n<p class=\"wp-block-paragraph\">The page <code>\/low_power.html<\/code> allows you to configure the publication thresholds for the <strong>ThresholdManager<\/strong> (4 channels: Display, BLE, MQTT, ESP-NOW) and the wake flags. The mode is also controlled from there (<code>lowPowerMode<\/code>) and sleep duration.<\/p>\n\n\n<h2 class=\"wp-block-heading\">Battery<\/h2>\n\n\n<p class=\"wp-block-paragraph\">The CO2 Gadget measures the battery voltage using a 100k\/100k divider (ratio 2.0) and averages 3 samples per reading. The display only updates when the voltage change is \u2265 0.1 V (to prevent flickering). You can configure <code>batChargd<\/code> y <code>batDischargedMillivolts<\/code> from the menu <strong>Settings \u2192 Battery Config<\/strong> (defaults: 4150 mV full, 3200 mV empty following the migration to v0.16).<\/p>\n\n\n<h2 class=\"wp-block-heading\">Important notes<\/h2>\n\n\n<ul class=\"wp-block-list\">\n<li>RTC variables are preserved during deep sleep (with a fallback to NVS)<\/li>\n<li>The T-Display S3 completely switches off the backlight (IC DW8904)<\/li>\n<li>The current calibration is retained during sleep<\/li>\n<li><strong>CO2 Gadget offers more advanced energy management than any other commercially available meter in the same price range<\/strong><\/li>\n<\/ul>\n\n\n<hr class=\"wp-block-separator\"\/>\n\n\n<p class=\"wp-block-paragraph\"><em>Did you find this helpful? Share this article. Have a look at the <a href=\"https:\/\/emariete.com\/en\/co2-gadget-guide-menu\/\">Menu Guide<\/a>. Any questions? Ask on the <a href=\"https:\/\/t.me\/emariete_chat\">Telegram group<\/a>.<\/em><\/p>\n<div class=\"essb_break_scroll\"><\/div>","protected":false},"excerpt":{"rendered":"<p>Gadget\u2019s Low-CO\u2082 Guide. Get up to 3 months\u2019 battery life from your high-quality CO\u2082 monitor: HIGH_PERFORMANCE and LOW_POWER modes, configurable deep sleep, battery management and wake-on-alert.<\/p>","protected":false},"author":1,"featured_media":243263,"comment_status":"open","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"_uag_custom_page_level_css":"","_lmt_disableupdate":"","_lmt_disable":"","footnotes":""},"categories":[13,16],"tags":[21,24,71],"class_list":["post-243031","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-co2-gadget","category-medidor-co2","tag-bajo-consumo","tag-co2-gadget","tag-co2-gadget-guias"],"modified_by":null,"uagb_featured_image_src":{"full":["https:\/\/emariete.com\/wp-content\/uploads\/2026\/07\/Blue_banner_with_white_text_202607050739_3.jpeg",1376,768,false],"thumbnail":["https:\/\/emariete.com\/wp-content\/uploads\/2026\/07\/Blue_banner_with_white_text_202607050739_3-150x150.jpeg",150,150,true],"medium":["https:\/\/emariete.com\/wp-content\/uploads\/2026\/07\/Blue_banner_with_white_text_202607050739_3-300x167.jpeg",300,167,true],"medium_large":["https:\/\/emariete.com\/wp-content\/uploads\/2026\/07\/Blue_banner_with_white_text_202607050739_3-768x429.jpeg",768,429,true],"large":["https:\/\/emariete.com\/wp-content\/uploads\/2026\/07\/Blue_banner_with_white_text_202607050739_3-1024x572.jpeg",1024,572,true],"1536x1536":["https:\/\/emariete.com\/wp-content\/uploads\/2026\/07\/Blue_banner_with_white_text_202607050739_3.jpeg",1376,768,false],"2048x2048":["https:\/\/emariete.com\/wp-content\/uploads\/2026\/07\/Blue_banner_with_white_text_202607050739_3.jpeg",1376,768,false],"trp-custom-language-flag":["https:\/\/emariete.com\/wp-content\/uploads\/2026\/07\/Blue_banner_with_white_text_202607050739_3-18x10.jpeg",18,10,true]},"uagb_author_info":{"display_name":"Mariete","author_link":"https:\/\/emariete.com\/en\/author\/admin_xlyz052h\/"},"uagb_comment_info":0,"uagb_excerpt":"Gu\u00eda de bajo consumo de CO2 Gadget. Consigue hasta 3 meses de autonom\u00eda con tu medidor de CO\u2082 de alta calidad: modos HIGH_PERFORMANCE y LOW_POWER, deep sleep configurable, gesti\u00f3n de bater\u00eda y wake por alerta.","_links":{"self":[{"href":"https:\/\/emariete.com\/en\/wp-json\/wp\/v2\/posts\/243031","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=243031"}],"version-history":[{"count":12,"href":"https:\/\/emariete.com\/en\/wp-json\/wp\/v2\/posts\/243031\/revisions"}],"predecessor-version":[{"id":243284,"href":"https:\/\/emariete.com\/en\/wp-json\/wp\/v2\/posts\/243031\/revisions\/243284"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/emariete.com\/en\/wp-json\/wp\/v2\/media\/243263"}],"wp:attachment":[{"href":"https:\/\/emariete.com\/en\/wp-json\/wp\/v2\/media?parent=243031"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/emariete.com\/en\/wp-json\/wp\/v2\/categories?post=243031"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/emariete.com\/en\/wp-json\/wp\/v2\/tags?post=243031"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}