Zero Energy Home in Edmond, OK

Ideal Homes built a Zero Energy Home (ZEH) in Edmond, OK, (a suburb of Oklahoma City) using an extensive package of energy efficient technologies and a photovoltaic array for site electricity generation. The ZEH is part of a demonstration project to exhibit high efficiency technologies, while trying to keep costs reasonable, with the objective of helping to put Zero Energy Homes within the reach of average home buyers. The ZEH is a modified version of Ideal Homes Plan 1644, or the ?Harper?, and is a 1584 ft2, 3-bedroom, single-story slab-on-grade design with attached garage. The home is designed to have an air tight, well-insulated envelope, and includes an energy recovery ventilator (ERV), high performance windows, tankless water heater, efficient lights and appliances, and a ground source heat pump (GSHP) for space conditioning. Photos of the ZEH are shown in Figures 1-2. The floor plan is shown in Figure 3, and key design specifications are listed in Table 1. The overall reduction in energy use is designed to be 88% compared to the Building America Benchmark based on preliminary analysis conducted by BSC. NREL and BSC visited the site in August 2005, and conducted a series of short-term tests to evaluate the actual performance of key building systems. NREL also performed annual energy simulations using DOE-2.2 and TRNSYS models based on the final design characteristics and short-term field measurements.

Two other Building America prototypes with expected energy savings over 55% were also built as part of this project: Plan 1451 and Plan 2314. Most of the energy efficiency features are similar, except the 1451 model has a solar hot water system with 64 ft2 of collector area, and the 2314 model has a GSHP desuperheater to supplement domestic hot water. These two houses have neither the photovoltaic system nor the ERV used in the ZEH. NREL conducted some additional targeted short-term testing of these prototypes as part of the field test.