In 1994, reconstruction of the photovoltaic array support frame was completed by the Alternative Energy class under the leadership of Bob Kobet. The original wooden support frame was decaying and in need of replacement. As a class project a design was completed for a new concrete and steel replacement.

In 2002 a new photovoltaic (PV) system was installed at the Harmony House during the 2002 Earth Week celebration. This PV system was designed to provide electricity for air and water pumps, which aerate the water being treated by the greywater system. The Macoskey Center staff designed the new system with the assistance of Michal Vojtisek-Lom and engineer from Buffalo, NY.

A photovoltaic array generates direct current for the house by converting sunlight into electricity. It requires no energy to run other than solar energy, and it emits no noxious gases or fumes. The direct current is converted by an inverter which rectifies it into a form suitable for running appliances that normally run on alternating current. Thus, electric lights, baseboard heaters, fans, and the refrigerator draw much of their power from the photovoltaic array.

The photovoltaic array has an output capacity of about 1.5 kilowatts AC. When the sun is up, the array generates elec- tricity. Any electricity generated in excess of what the house can consume is fed into the utility company power lines. At night, or when the house is using more electricity than the array can produce, electricity is automatically purchased from through the conventional grid supply system.

The photovoltaic array has a capital cost of $20,000. Data on power consumption are still being collected for the calcu- lation of the life-cycle cost of the photovoltaics.