HI Pat,
You may be thinking of one of two Solar Aquatics installations, one in Beaverbank, one in Bear River. I'm attaching my report (from 1996) on a field trip to Beaverbank. The concept must have been ahead of its time, apparently not supported by government and allowed to wither away. Too bad. I visited both and was very enthusiastic about the idea, as were the communities served by the systems.
Doug Linzey