What's the Solar Potential of Your New Solar-Home Site?

When you build a solar house, there's more to the story than just sun exposure. Solar takes into account water power, wind power, breezes, landscaping, thermal mass, and so on. Before you start planning a solar home, do some research by starting a log book. For each location you're considering, record facts, figures, and your observations for each of the following aspects:

• Know your solar exposures. What latitude are you in? What is the sun's path over the course of a year at that latitude? For each site, stand in the middle of the lot and plot the sun's course on a graph. You may have to do some guesswork about what the situation will be from a rooftop that hasn't been built yet. Different spots on a lot will have different solar exposures with different shading issues.

It goes without saying that you don't want to cut trees down. Look for deciduous trees and try to envision your house with those trees on the southern exposure, but not shading solar collectors on the roof. You can plant trees, but it will take a long time before they can rival natural, healthy, indigenous trees.

• Analyze prevailing winds. tabmarkNatural breezes are absolutely free and can make a major difference in the comfort of a home. Look for locations where hills magnify breezes in the summer. In the winter, you want natural brush and landscaping to block the cold winds from the north.

To thoroughly gauge the winds, you need to visit a potential location at different times of the year and in different weather patterns. Be patient in order to be thorough.

• Determine the water rights and drainage. Do you need a well? Wells have their advantages and disadvantages. You won't have a water bill, but you'll need expensive equipment. You can install a solar-powered well with a storage reservoir, and your water will be free forevermore. But wells can dry up, and the water can be of questionable quality.

You also need to determine the property's natural drainage. Some locations simply won't work for a home unless you radically alter the property's contour, which goes against the green mantra. How much water will your property require? Are you going to landscape? How will that affect drainage?

• Look into other factors. If you can, camp out for a day or two on a prospective lot. At the very least, visit at midnight, in the morning, and in the afternoon. Visit at different times of the year, if that's an option. What sounds do you hear? Who is moving around and when?

And don't forget to determine what may happen in the future. Are you going to have a shopping mall next door five years hence? How about a freeway? Or an airport? To find out about these kinds of things, ask your realtor and at your county building department.