Environmental Research Digest – March 2012
Altogether, the report identifies 99 existing and under-construction buildings that are either zero energy or zero energy-capable. The report identifies 21 occupied buildings with either measured net zero energy results (15 cases) or credible modeled expectations for such results (six cases).
- Zero-energy commercial buildings are both feasible and affordable, and they are appearing across the U.S.
- With the exception of two facilities completed in 2010 – Richardsville Elementary at 77,000 square feet and the NREL facility at 222,000 square feet – all ZEBs are less than 15,000 square feet, and half are less than 5,000 square feet.
- Interestingly, the study found that unique or experimental systems are infrequently used to reach net-zero goals.
- Most ZEBs are built using readily available technology.
- An integrated design approach with careful attention to building site and layout, envelope, mechanical systems, and electrical systems helps to achieve the highest level of energy efficiency.
- On-site generation with solar PV panels is another common denominator among existing ZEBs.
- The incremental costs for ZEB energy efficiency features range from 3 percent to 18 percent, depending on building type, size, climate and other variables.
- As the larger office buildings market moves towards ZEB, minimizing electrical loads from plug-in equipment and appliances, along with other miscellaneous or “unregulated” loads, is a priority.
- The emergence of new technologies will also be a factor in the expansion to more building types.
New Buildings Institute (NBI) / Zero Energy Commercial Building Consortium (CBC)