Building a Path Towards Zero Energy Homes with Energy Efficiency Upgrades

Dean Gamble, Brian Dean, and David Meisegeier, ICF Consulting
Jay Hall, Building Knowledge

Keywords

Abstract

The ultimate concept in advanced residential home design is to produce affordable and durable homes that consume no more energy than they produce. To achieve this goal, these “low/no energy homes” should combine energy efficiency and passive solar designs, with on-site (renewable) energy sources. With increasing public awareness of the U.S.’s growing dependence on unstable foreign oil supplies, risks of unstable energy prices, advances in photovoltaic technologies, rebate programs, and net-metering policies, it’s time to re-consider the design of low / no energy homes. While several demonstration “zero energy homes” have been built in the U.S., little information is available about how to best integrate load and demand reduction technologies with on-site generation equipment. Clearly, with aggressive efforts to reduce heating and cooling energy loads, the cost of on-site generation equipment (i.e., photovoltaic systems) can be substantially reduced.

This paper is an analytical study to assess how and where to most effectively integrate energy efficiency (EE) and passive solar features with on-site generation in new home designs. Structural upgrades, architectural design features, equipment & lighting upgrades, and behavioral modifications were analyzed to accomplish the maximum possible reductions in energy and demand. This information was then coupled with photovoltaic (PV) installation costs, rebates, and electric rates to determine which geographic regions and upgrade combinations work best together. The key finding of this paper is the identification of the “design conditions” where combined EE/PV packages achieved net overall costs that were comparable to the overall costs of standard code built homes.