We’re often asked how much more it costs to build a Zero Energy Home. This question has two answers.
The secret to a Zero Energy Home is to reduce the amount of precious energy the home needs to provide comfort and utility. This means being smart about the size of the home and constructing it to hold on to that energy as long as possible, not unlike the way a thermos keeps your coffee warm.
When we build this efficiently, we can actually provide comfort with the energy equivalent of a blow dryer (or two for larger spaces). In other words: Design the building to use as little energy as possible. Be miserly with energy!
Like that thermos, high performance homes are built airtight and have a building enclosure with high levels of continuous insulation, including triple glazed windows. High efficiency electric heat pumps provide heating, cooling, and hot water. Balanced heat recovery ventilation provides constant rates of filtered fresh air.
Of the approximately 500 items we use to construct a home, we need to invest in five to achieve this performance. We buy better windows, build thicker walls, use more insulation, make the home airtight, and fully insulate the foundation. These investments add appx. 5% to the cost to build, and are recovered in 5-7 years, with some of those costs offset by incentives and tax rebates.
These features are baked into the design of the home and as a result use appx. 80% less energy than a conventionally built new home. We apply the same principles to existing homes, though we may need to accept some constraints based on their structure and form.
Requiring dramatically less energy sets the stage for the rest of the equation: Harvesting solar energy to produce all the energy the home requires. Reduce, then Produce.
Our goal here is to “Electrify Everything” so that all our energy can be provided by clean renewable energy.
Rooftop solar panels are sized to satisfy this low energy load. The utility “banks” the excess produced in the summer and credits that for the additional energy you will need on shorter winter days when you are heating the home. The annual tally equals zero, and this performance is baked in for the life the home. That’s why we call these Zero Energy Homes.
By making smart investments in a home that can harvest the sun to produce as much energy as it uses, you are purchasing a long term predictable energy expense of zero. By taking advantage of available incentives, rebates, and favorable lending opportunities this is as financially smart as it is energy smart!