🔋 Power Saving with Deep Sleep

For solar-powered or battery-operated sensors in remote fields, deep sleep is essential. ESP32 can last months on a single charge!

📊 Power Consumption Comparison:

• Normal operation: 80-240mA
• WiFi connected: 120-180mA
• Light sleep: ~0.8mA
• Deep sleep: 2.5μA (0.0025mA!)

💤 Deep Sleep Example:

#include 

const char* ssid = "YOUR_WIFI";
const char* password = "YOUR_PASSWORD";

RTC_DATA_ATTR int bootCount = 0;

void print_wakeup_reason() {
    esp_sleep_wakeup_cause_t reason = esp_sleep_get_wakeup_cause();
    switch(reason) {
        case ESP_SLEEP_WAKEUP_TIMER:
            Serial.println("Wake up by timer");
            break;
        case ESP_SLEEP_WAKEUP_TOUCHPAD:
            Serial.println("Wake up by touch");
            break;
        default:
            Serial.println("Wake up by other reason");
    }
}

void setup() {
    Serial.begin(115200);
    delay(1000);
    
    bootCount++;
    Serial.println("Boot number: " + String(bootCount));
    print_wakeup_reason();
    
    // Connect to WiFi and send data
    WiFi.begin(ssid, password);
    while (WiFi.status() != WL_CONNECTED) {
        delay(500);
        Serial.print(".");
    }
    Serial.println("\nWiFi connected!");
    
    // Read sensors and send to OceanRemote here
    // ... your data sending code ...
    
    Serial.println("Going to deep sleep for 5 minutes...");
    esp_sleep_enable_timer_wakeup(5 * 60 * 1000000);  // 5 minutes in microseconds
    esp_deep_sleep_start();
}

void loop() {
    // This will never run
}
    

🔋 Battery Life Calculation:

With a 2000mAh battery and 5-minute wake intervals:

• Wake time: 5 seconds @ 150mA = 0.21mAh per cycle
• Sleep time: 5 minutes @ 0.0025mA = 0.00021mAh per cycle
• Total per cycle: ~0.21mAh
• Cycles per day: 288
• Battery life: 2000 / (0.21 * 288) = 33 DAYS
• With optimization and larger battery: 6+ MONTHS!