Heating, ventilation, and air conditioning for a superinsulated solar house

Abstract

Buildings consume about 70% of all electricity in the United States. There are many ways to reduce the energy consumption of a building and specifically a residential building. The Solar Decathlon competition promoted by the Department of Energy and the National Renewable Energy Laboratory force twenty university teams to find as many ways as possible to reduce energy consumption of a small house. For UIUC???s 2009 Solar Decathlon entry, the house was designed to be a certified Passive House, a way of designing a building to use 90% less energy for heating and cooling. The major path to certification is through superinsulation and supersealing of the building. This makes the heating and cooling loads small, requiring a novel HVAC system to provide heating, cooling and ventilation. From the simulated week of occupancy during the competition, where UIUC placed second out of twenty teams, the performance of the HVAC system is analyzed. Using a variable capacity compressor, saved UIUC???s Solar Decathlon entry 6.75 kWh or 24.32% electrical energy compared to a fixed capacity compressor. The HVAC system, in conjunction with the excellent thermal envelope, helped lead the team to a close second place finish in comfort zone, the measure of the HVAC system performance. In addition, the energy conservation measures of the HVAC system helped secure a second place finish in energy balance. The excellent performance of the HVAC system does not come at a price premium as it is less expensive than a comparable typical central air heat pump. All these benefits helped to define a house made up of many excellent technologies and practices