The good news: Solar housing is becoming a marketplace success. Eldorado, a rural subdivision near Santa Fe, New Mexico – with over 850 solar homes already built and more on the way – is a leading example of this trend. Eldorado accounts for 25% of all new single family housing in Santa Fe County.
Just nine years ago, solar homes were odd, their owners wore lots of sweaters, and appraisers and lenders were trying to understand just what this solar energy business was about. Things have changed: of 478 homes built in Eldorado from 1987 through 1990, all but four were solar. Even the elementary school is heated by the sun. And realtors there are finding non-solar homes are difficult to sell.
Builders in Eldorado are particularly generous with insulation of exterior walls and ceilings. Other strategies include sunspaces, massive floors and partition walls, and Trombe walls (thick masonry south walls with dark exterior surfaces covered with glass). One builder often includes a "half-Trombe" wall that allows for a view, but still provides the key advantage of an unvented Trombe wall – nighttime radiation of warmth collected, free of charge, during daytime hours.
The local electric utility has helped promote passive solar energy use by presenting design workshops, and by encouraging solar home owners to track their heat use on separate meters. It turns out that in Eldorado a typical 1,500 square foot, 3-bedroom solar home saves one-third to one-half what it costs to heat a traditional, non-solar home.
No wonder the non-solar homes are becoming a hard sell.
The bad news: Solar-thermal electrical generation, one of the big success stories of the late 1980s, is now in trouble because of federal government inaction.
Existing solar thermal plants are already providing Southern California Edison with 354 megawatts of clean power. Unfortunately, Luz International, the company that developed and built these plants, is now in trouble and may not be able to complete plants that would provide a wanted additional 320 megawatts.
Chief among the reasons is uncertainty caused by the expiration of a federal incentive – a ten percent Federal Energy Tax Credit – at the end of 1991. Related state tax credits in California depend on the federal incentive.
It would be tragic to have this renewable energy success story nipped in the bud, and lobbying efforts are underway to inspire the US Congress to restore these tax credits which create a level playing field with fossil fuels. For information on what you can do to help in this effort, write the address below:
American Solar Energy Society, 2400 Central Avenue, Unit G-1, Boulder, CO 80301. The Society publishes Solar Today, from which this was adapted.