This is a little modified code from user OK1CDJ.
ESP8266 with DHT11 including sleep mode code. To enable deep sleep on ESP-01 module you have to solder one wire like on this picture. You do not need to remove LED.
To change the sleep time shange this part of code. It is basically minutes*seconds:
node.dsleep(2*60000000) -- 2x60 sec or 2 minutes
--attempt to make this ESP-01 compatible
--wifi.sleeptype(wifi.LIGHT_SLEEP)
--tmr.delay(2*60000000) -- 2x60 sec or 2 minutes
--wifi.sleeptype(wifi.NONE_SLEEP)
Change secret.lua with your SSID, Password and you API Key from Thingspeak.
I suggest to use ESP8266 LuaLoader http://benlo.com/esp8266/index.html#LuaLoader for uploading the code.
To flash ESP8266 with firmware use ESP8266Flasher.exe This code has been tested with flash rom nodemcu_512k_20141219.bin
Capacitor used is 1000uF 6,3V
