dianaji - 3-31-2009 at 05:02 PM
i found this on another forum and would like to try this...now if i can find someone to help me get it installed.
If you get 4-5 hours of good sun you can build a simple solar water heater to use independently or tie into your existing hot water system.
The easiest and cheapest to build is a batch water heater. An old water heater tank works well. Remove any hard water deposits and replace the diodes
if badly corroded.
Paint the tank with flat black spray paint. Use the existing water inlet and outlet and I use pex pipe to attach this to my house plumbing. Cold water
goes in bottom outlet and hot water comes out top outlet to mix water.
Build an insulated box big enough to hold the tank and insulate around the bottom and sides of tank leaving only the surface you want exposed to the
sun uninsulated.
The box top should have a 45 degree angle from back to front to get more sunlight to the tank. Cover the top with a double or single pane of glass. An
old storm window works well for this and can be hinged for tank access.
Insulate all pipes as this is where heat is lost and freezing will happen.
HOW IT WORKS:
Place the batch heater so it gets direct sunlight. In 4-5 hours of good sunlight the water will be warm. In 6-8 hours it could be very hot.
If your batch heater is attached to your existing water heater it will reduce the electricity or gas needed to heat your water. If using independently
it will give you an adequate stream of warm water for showering and washing dishes.
large volumes of water hold heat along time and generally will not freeze quickly.
Batch heaters are generally only used seasonally in cold climates but you may get use out of it by covering the box with an insulating blanket on cold
nights to hold heat inside.
People use batch water heaters all over the world with great results.
light:
vgabndo - 3-31-2009 at 08:18 PM
We used to teach the expediency of building a hinged cover for the collector. (always double pane glass) It has to be built strong enough to
resist any expected wind loads, but 2" aluminized closed cell styrofoam does two important things. It can be adjusted to focus extra insolation into
the collector, and when closed at night provides insulation to the tank. The system doesn't have to "catch-up" so much in the morning. The night sky
will re-absorb the heat in the tank pretty quickly.
A batch heater is about as cheap a way as you can go. We were all about this in the 70's, then it became a SUV world, and a lot of that good stuff is
just collecting dust on my bookshelves now!