When plagued by mains power outages and unreliable security of supply, this little project based on a Arduino Nano and SIM800L GSM modules allows the user to :
 - Receive SMS notifications of mains power outages.
 - Receive SMS notifications of mains power restoration.
 - Remotely enable / disable two 220V 16A output channels for connected devices by means of an SMS command.
 - Receive SMS notifications of State of Charge of the connected LIPO battery.

Board is powered by 5V AC adapter under normal operation conditions when mains is available, an onboard LIPO 3.7V 1200mAh battery is charged and managed by a TC4065 single cell charging module.
During power outages the LIPO battery powers the Arduino Nano and SIM800L module with XL6009 module, stepping up the LIPO 3.7v to 5V required by the Arduino Nano.

On mains power restoration, the output channels remain off for a few seconds delay before their output state resumes their original state prior to the mains outage ocurance - this function seeks to protect the connected devices from line surges that may destroy sensitive equipment on restoration of the mains voltage after outage clearing.

Board is single layer home-brew home-etched design.