Seite - 50 - in Water, Energy, and Environment - A Primer

• highperformance electrical lighting • continuousinsulationprecastwallpanelswiththermalmass • windows that canbeopened for natural ventilation • radiant heating and cooling • outdoor air preheating, using waste heat recovery, transpiredsolar collectors, andcrawl space thermal storage • aggressive control of plug (‘vampire’) loads from appliances andother building equipment • advanceddata center efficiencymeasures • roof top andparking lot PVarray. US ZEB research is supported by DOE’s Building America Program, a joint effort with NREL, Lawrence Berkeley National Laboratory, Oak Ridge National Laboratory, and several industry-based consortia such as theNational Institute of Building Sciences and the American Institute of Architects. Many other countries are exploring ZEB’s as well, including jointly with the US through the International Energy Agency’s ‘Towards Net Zero Energy Solar Buildings’ Implementing Agreement (SolarHeating andCoolingProgram/Task40). This IEA program has now documented and analyzed several hundred net zero energy and energy-plus buildings worldwide (an energy-plus building generates more energy in a year than it consumes). An interesting example of ZEB technology applied to a residential home is NREL’s Habitat for Humanity zero energy home (ZEH), a 1280 square foot, 3-bedroom home in the Denver area built for low-income occupants. NREL report TP-550-431888(‘TheNREL/Habitat forHumanityZeroEnergy Home: a Cold Climate Case Study for Affordable Zero Energy Homes’) details the design of the home and includes performance data from its first two years of operation. The home exceeded its goal of zero net source energy andwas a net energy producer for these twoyears (24%more in year one and 12% more in year two). The report concluded that ‘Efficient, Water,Energy, andEnvironment–APrimer50