Our local state fair had someone demonstrating solar water heaters last year. They had the whole thing set up on the grass and they let you sample the water out of the tank with a spigot. It was overcast and rainy all that day and the water coming out of that tap was HOT!! I was just floored. I decided then are there that they day my water heater died would be the day that I installed a Solar Water Heater. The really cool thing about it, was that it required no pump to operate. The hot water moved through all on it's own. It also had evacuated tubes, so it was much more efficient as well and ideal for my rainy climate.
Good article on the topic
http://www.coopamerica.org/pubs/realmoney/articles/solarwaterheaters.cfm
Why am I bringing this up now? The fair is coming up soon and I really hope they're there again. So I thought I'd share!
Solar Water Heater Demonstration
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