Solar Domestic Hot Water and Heating Retrofit
As part of an energy-efficient renovation led by Springfield, VT-based All Seasons Construction, ARC installed a new heating and solar hot water system in three of 11 buildings of the Southview Housing development located on Stanley Road in Springfield, Vermont. All Seasons also installed new doublehung windows with three-quarter-inch low-E Argon glazing and dense-pack cellulose insulation.
This solar project was the third such system installed by ARC during the past year. According to Ted Chivers, president of All Seasons, “More owners are looking at these options today, and some of them promise attractive returns on investment with the reduction of utility expenses for the years ahead, and the increased property values.” (Valley Business Journal, April 2012).
Project Specifics
Solar panels, storage tanks, controls and new circulation systems and boiler injection pumps were added to building one to supply domestic hot water to all three buildings.
It was determined that eight 4’x10’ solar panels were required. The solar system is supported by two boilers and connected by attic piping from solar panels located on the roof of one building to domestic hot water storage tanks. The solar hot water is generated throughout the day and stored in a series of thermally-insulated solar tanks, totaling 240 gallons. This pre-heated, stored water acts as the cold water inlet to the indirect fired water heaters installed for the building. Two nearby buildings share in this system.
A typical system heats 40 degree F° water to the temperature that is required. The pre-heated water, which even on a cloudy day can reach 115 degrees, is then heated to the required set point by the indirect-fired water heaters that receive the additional required energy from the gas-fired boilers.
ARC also replaced four pumps in order to provide more efficient delivery of pumped hot water.
Mechanical Highlights
- Domestic hot water system consists of eight Heat Transfer Products (HTP) model FP40SC, 4’x10’ flat panels.
- Four 119-gallon SuperStor Contender, model SSC119, with internal enamel heat exchanger, indirect-fired water storage tanks.
- One Caleffi iSolar BX controller.
- One Caleffi solar pump station.
- One Caleffi solar expansion tank.
- One Amtrol model ST-42V hot water expansion tank.
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| Caleffi solar pump station. | Caleffi solar expansion tank. | Caleffi iSolar controller. | ||
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| Eight 4’ x 10’ HTP 450SC flat panel solar collectors. | Wilo Stratos hot water circulating pumps. | Four HTP, 119-gallon, SuperStor Contender, model SSC119, with internal enamel heat exchanger, indirect-fired water storage tanks. | ||
