Posts Tagged ‘case study’

Solar Hot Water Turns Oil Boiler Into Backup Unit for Bow, NH homeowners

Wednesday, November 16th, 2011
Solar Hot Water System Bow, NH
The solar hot water system for Bow-based homeowners Gail and Leon Kenison allows them to use their oil boiler for backup only, with a wood stove for primary heating.

We had a chance to speak with Gail Kenison, a homeowner in Bow, New Hampshire who recently had us install a cost-effective solar hot water system that will essentially keep the boiler off from May to October.

Gail and her husband, Leon, had already cut down oil use in their home dramatically by choosing to heat primarily with wood. In the winter, their oil boiler still served as a source for hot water and backup space heat. But with their boiler running throughout the summer for the sole purpose of heating water, they decided to take the next step and invest in solar hot water.

“We’ve tried to stay in tune with all the renewable energy options, and had wanted to do something for a while,” Gail says, “We learned about solar at a continuing education class, and discovered that solar thermal presented a great solution for our home.”

Solar Hot Water Works

The Kenisons had ReVision Energy install two American-made Chromagen 4×8 flat plate solar hot water collectors and an 80G super insulated dual-coil solar storage tank. Whenever the rooftop collector temperature is hotter than the water at the bottom of the 80-gallon storage tank, a differential temperature controller automatically activates the solar circulating pump, which pumps solar-heated propylene glycol (a sugar water antifreeze solution) down from the collectors and through the bottom heat exchange coil in the tank, thereby transferring the heat from the sun to the water in the tank. The system includes automatic hot water backup from the oil boiler for those times of year when the solar resource is not strong enough to meet 100% of domestic hot water demand.

“The experience has been great so far,” Gail says, “The install team was knowledgeable, very professional, and clearly took the time to do the job right. They made us feel very comfortable with their work and took the extra time to help us understand the system. We couldn’t be more pleased.”

Even as the Kenison’s solar thermal system enters the heating season, it should produce up to half of their household’s hot water. Since they’ll be heating primarily with wood, that means their boiler will only need to run as a backup for both heat and hot water – creating some substantial fuel savings and CO2 reductions!


Solar Calculator