Green Day

October 4 was a glorious and appropriately sunny day for the Green Buildings Open House, a national event whose Massachusetts segment was hosted by the Northeast Sustainable Energy Association (NESEA). I visited several houses outfitted with sustainable energy sources, two of which deserve special mention.

The first was owned by a delightful guy named Bob Gagnon, who is a plumber by day and a do-it-yourself engineer by nights and weekends. He has outfitted his little Colonial with an immense amount of radiant tubing-in floors, walls, and ceilings--through which he pumps water warmed by two different types of solar collectors, the old-school homemade box kind, really just a bunch of black-painted copper tubes in a black-painted box, and an array of up-to-the-minute vacuum tubes. With huge water tanks in his basement to serve as banks for the heat he harvests, he now heats his home and gets his domestic hot water completely free of his boiler. The lesson he's learned is that solar-derived hot water matches perfectly with the lower water temperatures required by radiant heat. He explains his commonsensical approach at: www.bobgagnon.com/SolarRadiationPage.htm

While I was there, another visitor told his own sustainable energy story. He'd just installed a photovoltaic array on his roof that takes care of all his electrical needs and then some, which he sells back to the electrical utility. It cost about $30,000 to install, but he got $15,000 worth of rebates and tax credits (Massachusetts has a clean-energy fund homeowners can draw on and, as you may know, the federal solar tax credit was given an 8-year extension in the recent $700 billion Emergency Economic Stabilization Act.) He estimated he'd be making money off his roof in about 7 years.

The other house caught my attention for a couple of reasons. Not only was it a killer brick-end Federal from the 1800s, it was heated and cooled by a ground-source heat pump, aka a geothermal system, powered by solar electricity. While deeply cutting a home's use of fossil fuels, one flaw in geothermal systems (aside from the costs of drilling deep holes in the ground) is that their pumps use quite a bit of electricity, which partly negates the greenness of the application. Solar electricity closes that loop, and it was wonderful to see an antique building with a state-of-the-art heart ticking away inside.

An aside: this particular house was perched on a hill in the countryside, with its solar array laid out in the back yard. I'm a member of the Cambridge (Mass.) Historical Commission, and we're seeing more and more cases of people seeking permission to mount solar power equipment on their (often historic) roofs; most if not all get approved. I think there's a strong sense that a certain energy future has arrived and accommodations should be made for it.

Final note: NESEA puts out a very good magazine called Northeast Sun; the fall 2008 issue features a fairly exhaustive "sustainable green pages" of 35 green building specialties-from Alternative Technologies to Windows. Click here for more information.