I built a solar heater out of 210 beer cans. It's heating my office downstairs as I type. I work from home so the timing is perfect for a solar heater. I turns on automatically each day at around 9am and stops are 4pm. If the clouds come over the fan shuts down and waits for the panel to get hot again. I had to drink a lot of beer but also scavenged cans from shopping center bins etc:-) See photos attached.

Rated: for Overall Experience.