Power Consumption

https://www.electronicwings.com/esp32/esp32-deep-sleep-mode

Connect board VIN (red wire) to Arduino 5V if you are running a 5V board Arduino (Mega, etc.). If your board is 3V, connect to that instead.
Connect board GND (black wire) to Arduino GND
Connect board SCL (white wire) to Arduino SCL
Connect board SDA (blue wire) to Arduino SDA
Connect Vin+ to the positive terminal of the power supply for the circuit under test
Connect Vin- to the positive terminal or lead of the load

#include <Wire.h>
#include <Adafruit_INA219.h>

Adafruit_INA219 ina219;

void setup(void) 
{
  Serial.begin(115200);
  while (!Serial) {
      // will pause Zero, Leonardo, etc until serial console opens
      delay(1);
  }

  uint32_t currentFrequency;
  Serial.println("Hello!");

  // Initialize the INA219.
  // By default the initialization will use the largest range (32V, 2A).  However
  // you can call a setCalibration function to change this range (see comments).
  if (! ina219.begin()) {
    Serial.println("Failed to find INA219 chip");
    while (1) { delay(10); }
  }
  // To use a slightly lower 32V, 1A range (higher precision on amps):
  //ina219.setCalibration_32V_1A();
  // Or to use a lower 16V, 400mA range (higher precision on volts and amps):
  //ina219.setCalibration_16V_400mA();
  Serial.println("Measuring voltage and current with INA219 ...");
}

void loop(void) 
{
  float shuntvoltage = 0;
  float busvoltage = 0;
  float current_mA = 0;
  float loadvoltage = 0;
  float power_mW = 0;

  shuntvoltage = ina219.getShuntVoltage_mV();
  busvoltage = ina219.getBusVoltage_V();
  current_mA = ina219.getCurrent_mA();
  power_mW = ina219.getPower_mW();
  loadvoltage = busvoltage + (shuntvoltage / 1000);

  Serial.print(busvoltage);
  Serial.print(",");
  Serial.print(shuntvoltage);
  Serial.print(",");
  Serial.print(loadvoltage);
  Serial.print(",");
  Serial.print(current_mA);
  Serial.print(",");
  Serial.print(power_mW);
  Serial.println("");

  delay(50);
}

source code

Power Consumption

Energy Harvesting