We are supplying renewable energy to the building through a combination of photovoltaic, solar hot water, and a geothermal heat pump. The photovoltaic contribution is straightforward. The solar and geothermal is less clear. How much energy does the ground contribute? We are using the amount of energy it takes to run the geothermal system as a percentage of the total building load. Is this a reasonable way to calculate the renewable energy contribution?
The contribution of the solar hot water heating should be calculated by determining the avoided load for water heating. The committee has ruled that ground coupled heat pumps do not qualify as a renewable energy source. The benefits this technolgy provides is in energy efficiency, which helps capture Energy Credit #1. Applicable internationally.