im not totally off grid but i have run into a few power outages lAST one was for 6 hours on a cold winter night in newhampshire . the system ive set up kept my lights freezers and HEAT going no problem /open the doors all you hear is generators for miles i sleep like a baby no noise at all ... I personally wont do MPPSOLAR but must say the people {ian } at growatt is alot of help and a strait up guy . ive now got 2 of them wired together split faze 24v volts 240 i can run anything under the sun