Our office has completed a number of residential and institutional projects designed to achieve net-zero status through the integration of a roof-top photovoltaic system as well as comprehensive energy saving strategies. Our largest net-zero project to date is the Catherine Houghton Arts Center at The White Mountain School in Bethlehem, NH. Although the building was dedicated in February 2014, its 43kW roof top solar panel system was not installed until late November 2014, just as winter snow storms arrived. More than a foot of snow had to be shoveled off the roof for installation, and the panels were covered in snow and did not really begin generating power until April of 2015! The intermittent nature of solar and the unforgiving northeast climate meant that the building would have to pivot back and forth between its solar power source and the grid for power throughout the year.
Despite these hurdles, the photovoltaic system still managed to generate enough electricity to power the arts center including its geothermal heating system, as well as net-metering group member buildings which consisted of a 12-student dormitory with 2 faculty apartments, and a separate 3-bedroom faculty house. During its first few years of operation, the rooftop photovoltaic array generated 100% of the arts center’s power needs (11 kW per year) plus between 84% -100% of the other two buildings’ power needs (22 kW). Guess that means that the arts center isn’t only a net-zero building but is a net-positive power plant!