Design your house and lot appropriately from the beginning.Building a new home? Take steps from the very beginning to make your house “solar friendly!”
Most solar equipment, including both solar thermal (water heating) and solar electric (photovoltaic) systems, need to be aimed to the south. Orienting your home so there’s lots of roof with a southern exposure will let you take full advantage of the sun to heat water and/or generate electricity.
Roofs in Hawai‘i are generally at a good angle for solar equipment. For best year-round operation, solar devices are installed at an angle roughly equal to the latitude, usually plus approximately five degrees. However, there’s some “wiggle room” here; the tilt does not need to be exact. Unless you have a flat roof, your solar collectors or photovoltaic modules will probably be okay installed at the same angle as your roof.
When you’re planning your landscaping, keep in mind that solar devices need sunshine year-round. In the winter, when the sun is lowest, it will be about 45 degrees above the southern horizon at midday. Try to avoid planting tall trees, which will shade your south-facing roof in the winter.
Of course, your solar equipment doesn’t have to go on the roof of your house! That’s merely the most convenient for many people. You will rarely find solar water heaters installed anywhere other than a rooftop. However, some people prefer to have their photovoltaics mounted on a garage or shed, which can hold the inverter and other equipment (especially if there are batteries and a back-up generator). There are also pole mounts that enable you to put a half-dozen or more photovoltaic modules in a sunny area of your property, if you don’t want them on your roof for some reason.
Some photovoltaics are incorporated into the actual roofing material—laminated directly onto metal, so you don’t need to add another structure to your roof.
Whatever your “dream house” will look like, it will be much easier to add solar equipment if you design your home and lot appropriately from the beginning.
In partnership with the state’s energy office, the Maui Weekly provides this feature to help Valley Isle homeowners reduce their utility bills and increase their environmental awareness. For more information, visit www.hawaii.gov/dbedt/info/energy.