Yellowlite installed a 5 KWH system on my roof a couple years ago. They were polite and professional during the installation process, and they gave me a reasonable price. However, the battery back up installation that I paid an extra $2000 for is worthless after 3 years. It powered my house recently during a test "outage" for me for 20 minutes, under low power consumption. There have been other bugs in my system which have crippled it sometimes for weeks at a time. It is generating power, to a degree, but I think that it will take longer to earn back my initial investment in it. If I could go back I would not do the battery back up system. Better to just get a generator.