|A 12.5 kW PV system produces a yearly net surplus of electricity.||Belgravia Green Home in Edmonton, Alberta, Canada||SIP construction makes a tight and well-insulated building envelope.||A heat recovery ventilator (top) keeps the air fresh without undue heat loss.|
This profile details one of two homes in Edmonton, Alberta, Canada’s Belgravia district. The home was built as a show home by Effect Home Builders (EHB; effecthomes.ca), an Edmonton company known for its energy-efficient houses. Flanking it are two privately owned custom homes—and all are designed to approach or achieve net-zero energy status.
According to Les Wold, EHB’s managing partner, “One of the big things we’ve learned is that there are multiple ways to approach building energy-efficient homes—that’s what we really like about this project. There are three different homes and they are all reaching toward the same goal, but approaching it with different considerations and different technologies.”
Central to the homes’ efficiency is the building envelope—an important factor in any energy-efficient design. All three houses achieve a high level of airtightness, and HRV systems are used to exchange stale indoor air with fresh outdoor air, while retaining most of the heat in the air.
A net-metered, grid-tied PV system meets all of the show home’s energy use over the year. The other two homes are PV-ready, with a conduit run from the mechanical room to the roof. Although solar generation is only one part of the additional cost incurred when building net zero, Wold estimates that the cost of building net-zero ready is only about 7% to 8% more than a standard house.
|This air-source heat pump provides a means of efficiently heating and cooling the homes.||EHB’s Les Wold poses with the grid-tied PV array, which features microinverters.||A wood stove provides supplemental heating, if needed.||South-facing windows and a thermal mass floor are archetypes of passive solar design.|