(The following are excerpts from an article included in “The Pipeline,” published by the Plumbing-Heating-Cooling Contractors of Greater Boston and United Association Plumbers and Gasfitters Boston Local 12.)
Boston, MA – The drop in oil prices that accompanied the 2008 economic collapse helped the Boston area dodge a bullet this past heating season. But the law of supply and demand dictates that oil and other non-renewable energy prices will eventually spike—perhaps dramatically. That and a host of other reasons (including the push for environmentally sound green alternatives, new tax credit programs, and the imperative to wean the nation off of foreign oil) have led to a renewed interest in solar energy systems.
Andy Lyne, Jr., the president of A. J. Lyne, Ltd. of Abington., initially became involved with solar energy when he purchased his first house in 1986 and discovered that its solar hot water system had been incorrectly installed. He revamped it, and learned about solar concepts and techniques in the process.
In 2005, the Lyne company began installing its first full solar system at Tufts University. As with a lot of construction projects, customer demand played a role in the decision to incorporate green technology.
Tufts decided that it wanted to supplement the traditional hot water system at its new Sophia Gordon Hall dormitories with a solar system. The college called in Lighthouse Electrical, a Massachusetts-based union contractor with expertise in solar, wind, photovoltaic, and other alternate energy installations, to perform the work. In turn, Lighthouse brought in A. J. Lyne to handle the plumbing part of the project.
According to Lyne, the Tufts project is an open-loop drainback system. Water is pumped up to 25 solar thermal panels on the dorm’s roof where it is passively heated and drained back to a tank. A heat exchanger transfers the heated water to two 400-gallon storage tanks in the basement. The tanks’ water then preheats the dorm’s primary indirect-fired water heaters.
“The basic piping principles were the same for the Tufts solar project as a conventional hot water system,” says Lyne, who also notes that the job required a lot of piping. “But we did have to use some different components, such as a flow meter, BTU monitors, sight glasses, and a control for freeze protection.”
Along with other green measures, including energy-efficient windows, motion sensors that turn lights off when nobody is present, and dual-flush toilets, Tufts estimates that its 62,000sf, 126-bed dorm is using 30 percent less energy and 30 percent less water than a comparable non-green building.
Hope Lodge’s closed-loop system
More recently, A. J. Lyne installed the piping and plumbing components for a solar hot water system at a new building for the American Cancer Society in Boston. Unlike the Tufts job, the ACS project uses a closed-loop system. Instead of water, the system uses glycol, which is heated by 17 roof-mounted solar panel collectors. Exchanger blocks transfer the heat to a large water storage tank (which Lyne dubs a “kiddie swimming pool”), and the tank provides preheated water to high-efficiency, on-demand, wall-mounted water heaters.
The solar system is used to provide hot water for the ACS’s Hope Lodge Center, which opened in October 2008. About a mile from the Dana-Farber, the Center offers 40 suites for out-of-town families to stay while their loved ones receive hospital care.
Solar can be a pricey option. But commercial applications, such as Hope Lodge and Sophia Gordon Hall, have a much greater demand for hot water than residential systems, and are therefore able to recover their energy costs faster.