After years of being perceived as a luxury product, the price of zero-energy homes has come down to the point that they’re now ready for “mainstream markets”, the Rocky Mountain Institute reports in a recent analysis.
While some media have suggested price premiums of up to 40% for zero-energy designs, the “economics for these homes have changed: ZE homes have quietly passed cost thresholds that make them not only good for the environment but also cost-effective,” RMI states. “As the underlying technologies and design elements continue to improve and scale, these costs will continue to decline.”
The institute states that the additional cost of zero-energy homes is now below 3% in most parts of the United States, and below 1% in “select locations” like Houston. “Developers may even be able to construct these homes at cost parity in locations with stricter baseline codes (our analysis assumed construction meeting the 2009 International Energy Conservation Code), and aggressive incentive offerings from local utilities.”
But that’s not the only criterion. “Savvy consumers consider upfront and ongoing costs in a variety of everyday purchasing decision,” and today’s ZE homes are now competitive across four key “cost thresholds”: energy costs over the life a mortgage, energy savings over the average 12 years that a homeowner will stay in the home, consumer willingness to pay the threshold, and the incremental cost compared to a standard house.
While the comparisons vary across hundreds of combinations of different energy-saving measures, the common denominator is RMI’s expectation that the cost of zero-energy homes will continue to drop over time.
“Industry progress and demand for super-efficient building components is expected to drive cost savings over the next decade,” the institute states. “Specifically, our projected cost decline is a result of solar PV costs dropping, reduced PV system size requirements (due to equipment efficiency gains), and efficient equipment becoming more mainstream.”