Comment by punkgeek

we are careful to keep the esp clock-gated almost all the time (esp calls this light-sleep), in that mode the power draw of the ESP is on 1.5mA. When the radio (or button press) receives a packet it wakes the main CPU, which then services everything (turning on bluetooth as needed) and then goes back to sleep. If you are curious for more details we have a power consumptions spreadsheet in our docs.