Evacuate tube solar

[GaryGary]

You might consider building a separate system for heating your pool. You could a bigger/cheaper/dumber array that just circulates pool water w/o any HXs, and maybe without any real glazing....there are also low cost solutions you can buy. I would save the nice, durable, well glazed, freeze safe panels for DHW, and those could then be sized a lot smaller/easier/cheaper, and matched to a smaller tank.

I agree with WoodGeek that using commercial pool heating collectors for the pool would probably be the best choice. They run about $5 per sqft and even though they are unglazed they are quite efficient for spring, summer, fall -- reason being that the pool water is usually cooler or about the same temperature as the ambient air, so glazing is not needed to reduce heat loss, and you don't have the 10% loss from sun absorbed the glazing itself. Most of these collectors are a polypropylene mat with the water tubes spaced very close together.
There are lots of them on ebay.
Some samples of the kind of systems DIYers have done for pool heating here: http://www.builditsolar.com/Projects/PoolHeating/pool_heating.htm

If you want to heat the pool with solar through the winter, then you probably need the glazed collectors.

Gary

 

[MarkW]

I want the heat from collectors year round. As much as I can reasonably absorb. I've been heating my pool with a simplistic absorber gridwork and have been impressed with the amount of heat one can get on a sunny day. I want more!

I spent a lot of time on the BIS pool heating pages in the past, Gary. Thanks!

FWIW, I'm not a fan of store bought anything. Maybe it's a sickness but I'm just sure I can make better, myself. Obviously, there are limitations to the DIY approach but FP collectors aren't one of them, IMO.