ZNE Home Retrofit

Southern California Edison’s (SCEs) Emerging Technologies Program (ETP) seeks to demonstrate residential measures to potential users in order to disseminate information on energy solutions and encourage their widespread application. A Zero Net Energy (ZNE) Project was initiated, as part of its ETP Demonstration Showcase (D/S) Program, to identify energy efficiencies and renewables suitable for low-income residential housing within SCE's service territory. This ZNE Home Retrofit (ZHR) project will demonstrate these opportunities in building performance and energy usage associated with a combined package of energy efficient measures, smart appliances, and on-site renewable energy with the objective of achieving ZNE or near ZNE at a residential site in San Bernardino. The ZNE Home Retrofit project aligned with these stakeholders’ efforts of developing housing and community awareness in energy efficiency, environmental quality, alternative materials and resources, and water conservation. The project provided insight to local workforce training programs. Community programs, such as “ReBuild” IE (Inland Empire), were launched in late 2011 to stabilize neighborhoods hit hard by the foreclosure crisis. By purchasing and rehabilitating foreclosed properties, and making them available to first-time and low-to-moderate income buyers, NHSIE offers the dream of homeownership to those who have been unable to compete with cash investors on desirable properties conducted by NHSIE.” The rehabilitation of their community homes included energy efficiency in building performance. Homes that have the basic off-the-shelf energy efficient (EE) components can achieve building performance with a tightly sealed thermal envelope, solid-state lighting, energy-efficient doors and windows, high-efficiency heating and cooling systems, and Energy Star® approved appliances. This combined package of EE measures prepares a home for ZNE opportunities with required renewables. The majority of the low-income homes within this community were constructed during the 1960’s. Their building performance consisted of loosely sealed thermal envelopes with fatigue aluminum slider windows retrofitted with duct tape and quilts to reduce the transfer of solar thermal and air infiltration into the conditioned space. The selected project site shared this building design that came with only gas wall heating. Air-conditioning (AC) was implemented using six plug load, window-inserted AC units. This equipment, lighting, and the appliances rated well below the required energy efficiency standards. This was typical throughout the neighborhood within this community. The ZHR Project outreached to these community stakeholders with a provision of information and services associated EE measures (EEM) and renewables could be incorporated within their programs for developing local workforce, housing and community awareness. In February of 2011, the ZHR project team developed a retrofit plan that provided residences various approaches to EE measures and renewables, construction best practices, and the prevention of potential risks. The plan benchmarked potential energy efficient solutions (PEES) using the eQuest simulation tool to affirm the selection of EEMs and renewables. The Project Design was able to model a 105% ZNE design. However, the economics for a low-income ZNE home retrofit did not support the modeled results. It accomplished major retrofit measures securing higher efficiencies for the homes’ building envelop, interior and exterior lighting, appliance plug loads, tankless Domestic Hot Water (DHW) heater, and a renewable energy source. The measures installed are technologies offered with existing SCE Incentives and Rebate Residential Programs.