If you are considering solar for home heating there is a lot to learn. Unless your home is designed as a solar home, you will not be able to use solar as your sole, or perhaps even primary, heating source. Solar heating can reduce your dependency on fossil fuels and electricity for heat. There are two main types of solar heating, passive and active. Active solar heating requires mechanical installation and is best done by professionals.
Active solar for home heating systems come in two types, solar air and solar liquid. Solar collectors need to be placed on the roof of the home or on a wall or other structure. The collectors must face true south (not magnetic south) for maximum efficiency. The collectors should be installed at an angle of your latitude plus 15 degrees.
In general, solar air systems are best utilized to heat one or two rooms. An air system uses air to absorb and transfer the heat from the collectors to your home. One advantage of air systems is that they produce heat earlier in the day and continue to produce heat later in the day than liquid systems. Air systems will not freeze and burst pipes like liquid systems can. They can also be used to send heat directly to an individual room.
You can buy a small passive solar air heater for a single room. The collector fits into a window opening and air comes in through the bottom of the heater, is heated in the collectors and released through the top of the heater into the room.
Solar for home liquid heating systems are more practical than air systems as a rule, but they are expensive to install and still require a back up heating system. The most efficient solar for home liquid heating systems use radiant floor heating. Tubes are installed in a thin concrete slab and the heated liquid is passed through the tubes. The floor is usually covered in tile because carpet cuts down on the system efficiency. Since heat rises, by heating the floor the entire room gets heated. These systems can also use forced hot air, baseboard and radiators.
One problem with using baseboard heating with this system is that solar for home heating systems only heat the water to about 120 degrees, which is about 40 degrees less than electric or gas heaters. In order to heat the room you must have a lot more baseboard area, or use a conventional heating system to warm the water to higher temperatures. Even if you use a conventional heating system to supplement your solar hear, you will still save a considerable amount of energy.
Solar for home heating systems have a number of drawbacks, including the fact that the solar collectors are not especially attractive. The technology is still in its early stages and is continuing to improve. While the expense and other factors may currently deter many homeowners from the use of these systems, improvements in the technology will probably make solar for home heating more practical and affordable in the near future.