While ongoing development of codes, legislation. and green building rating systems continue to raise the ante on the market’s expectations for high-performance building projects, net-zero energy buildings still remain elusive – especially in the private sector.
There are several reasons for this, but the primary hurdle is the economic viability of systems for on-site renewable energy production (e.g. solar panels, on-site wind turbines, and so on).
To explain the current economics of solar panels in terms that I feel are most relatable to the casual reader, consider a typical two-story 2,200 square foot (all electric) residence in Indianapolis. A house of this size would likely need a 10-kilowatt solar panel system size in order to achieve net-zero energy (i.e. over the course of a year the solar panels produce at least as much electricity as the structure consumes). At $7 to $9 per rated watt, a 10-kW systems would cost between $70,000 and $90,000 dollars – before any rebates, tax incentives, etc. Even if a homeowner could knock off 50% of the system cost with incentives, that’s still $35,000 to $45,000. At the reduced cost, we’re still talking a return on investment well over 20-years.
Despite this and other significant hurdles to net-zero energy design, there does appear to be a growing market for such projects – a niche which is projected to blossom in coming years as the design and construction industry calibrates in a healing post-recession market that is ever more concerned with energy and resource efficiency.
Lincoln Heritage Public Library’s Chrisney Branch, the first net-zero energy public library in Indiana. In 2008, I assisted with the research and energy modeling for the project at Browning Day Mullins Dierdorf Architects. Image courtesy of Morton Solar and Wind.
Building Design + Construction magazine has recently released a collection of eight white papers that detail the various facets of the burgeoning market for net-zero energy buildings and homes. The white papers offer a well-rounded, comprehensive snapshot of the current state of the net-zero energy building market and I would encourage anyone to read the papers.
All eight white papers are available for free at http://www.bdcnetwork.com/article/2011-zero-and-net-zero-energy-buildings-homes