Solar energy is (finally!) becoming very popular these days, with individuals, businesses, and energy companies all embracing whichever form of solar energy is most appropriate for their needs. Overall, this is a very good thing, but some forms of solar energy are more benign, and more desirable, than others.

Let me briefly mention here two of the very best forms of solar energy. One is commonly termed “rooftop solar”, where individuals or businesses put photovoltaic panels on their home or workplace roofs. Photovoltaic (“PV”) panels are made up of numerous small “solar cells” that are capable of converting sunlight directly into electrical energy. One photovoltaic cell doesn’t produce very much electricity, but a dozen or so panels on your roof can produce enough power to meet the needs of the average household (depending on how many people live under the same roof with you, of course). The roof of a very large “big box” or department store can produce an impressive amount of electricity.

“But wait!” (as they say in the TV ads), there’s a second big benefit as well. With the sun’s rays (and heat) hitting the solar panels instead of your roof, your roof (and the attic or rooms under it) will stay cooler, since they are now in the shade of the panels. Thus, the solar panels help keep your house (or office building) cooler, and thus reduce your air conditioning bill as well. Such a deal!

The second “can’t lose” form of solar energy is called “passive solar”. There are a great many variants of passive solar, but perhaps the most common involves designing a house in such a way that solar energy will come through large glass windows in the winter months, and hit a dense, dark colored, heat-absorbing wall. At night, the wall will re-radiate the stored heat throughout the house. A system of ducts, and maybe a small circulating fan, might be needed too. This is not the best system for southwest deserts or the rainy Olympic Peninsula, but over most of the United States it’s a great energy saver. It is most economical to install a a passive solar system when a house is first being built, as retrofitting can be very expensive. Many books have been produced about passive solar systems. If you’re thinking of building a house, it’s well worth looking into.