Solar Heating Plan for Any Home

Image Gallery Gary Reysa’s home in the foothills of southwest Montana. Heat collected in the shed (right) is transferred to the house (left) via underground water pipes. The collectors on the garage (middle) heat the garage with solar-heated air. GARY REYSA

It’s time to take advantage of solar heat to reduce your dependence on fossil fuels and lower your heating bills. This simple, yet effective, system can be utilized in almost any home. Because the solar collectors and the heat storage tank for the system are built into a small new outbuilding, you don’t need to completely remodel your home to use solar heat. On sunny days (or even partly sunny days) the collectors add heat to the storage tank. When the house needs heat, hot water from the storage tank is transferred to the house via an underground pipe into a radiant floor heating system. (See illustration in the Image Gallery.) The new building that houses our collectors is a storage shed, but yours could be a studio, playhouse or workshop.

Advantages of This Approach

• The collectors are mounted at ground level, where they are easy to build and maintain.
• The collectors can be oriented and tilted for maximum solar collection.
• The collectors and the building can share a structure in such a way that the material costs and time to build are reduced for both the collectors and the shed.
• The collectors look good integrated with the shed (see photo, Image Gallery).
• You don’t have to find a space for a large thermal storage tank in the house.
• The steeply tilted or vertical collectors located close to the ground benefit from light reflected off the ground, particularly when the ground is snow covered. And, vertical or near vertical collectors are less prone to overheating in the summer.

Considerations

There are many ways to build this system, but remember these design guidelines to ensure that your system works well:

• The collectors should face within 30 degrees of true south and should not be shaded by trees or structures during the three hours before and after solar noon. Be sure to check carefully for any obstructions that would shade the collectors (see “Solar Site Survey” in “Resources,” below).
• To minimize heat loss from the pipes that carry water to the house, the collectors should be as close to the house as possible. The pipes should be well insulated and the trench should be deep enough that the pipes are below the frost line for your area.
• The thermal storage water tank must be well insulated. This requires careful insulation and careful sealing of the tank lid.

The system that distributes the heat within the house should be able to use water that is as low in temperature as possible. Lower temperature water for heating will allow the solar collectors to operate more efficiently and collect more heat. We added a radiant floor heating system to distribute the solar heat throughout our home. This radiant floor can make use of water as cool as 85 degrees to heat the floors.