Stellwagen Bank National Marine Sanctuary is dedicated to reducing the impact of our facilities and operations on the environment. The renovation of the main building and meeting annex in 2004 incorporated energy saving features, such as thermopane windows and energy-saving LED lights. The most innovative component is the heating and cooling system.
Our headquarters office building was the third NOAA building in the nation to incorporate a geothermal system. This HVAC system reduces dependency on fossil fuels by using the earth as a heat source in the winter and a heat sink in the summer. The subsurface soil, groundwater (salt and fresh), and bedrock maintain a constant temperature of about 58 degrees Fahrenheit. The difference in temperature between the 58 degree earth and the ambient air is what drives the system. In the winter, the closed-loop system, using a special chemical refrigerant, draws heat from the ground and transfers it to the building space through ground-source heat pumps via a heat exchanger. In the summer, it extracts heat from the building's interior and transfers it to the ground.
Ultimately, the geothermal HVAC system is 50-70% more efficient at heating and 20-40% more efficient at cooling than a conventional, fossil-fuel fired system.