It's hard to know how much wood you need until you try out your heating system. A well-insulated house may use 2-3 full cords of hardwood and a little softwood every year. In comparison, a smaller contemporary stone home with no insulation could use 6 full cords. An inefficient outdoor boiler may use 3-4 times more wood than a high-efficiency indoor stove. The general rule of thumb is to purchase more than your heating needs. If your wood is covered, it can last at least 3 years without rotting. You won't be wasting your money.

Pool Heating with Solar

It's important to make one thing very clear when discussing piping materials for a solar thermal installation: copper or stainless steel are currently the only sensible choices.

It may be tempting to try to use a flexible material like rubber or Pex, but it won't work: there's a very good chance you'll have to replace all your piping within the first year of operation because it simply cannot withstand the constantly high operating temperatures of the system.

You can find plenty of water heating systems using solar energy today, including home-built designs that are simple but effective, like the batch heater. This design has no outer jacket or insulation blanket but is painted black and placed in an insulated plywood box. There is a plastic or glass glazing covering the assembly, which is angled to solar south. Pressurized domestic water goes into the tank’s bottom and heated water comes out from the top to your home’s hot water heater.