Flawed energy efficiency modeling is the reason many green buildings fail to live up to expectations on energy efficiency, according to a U.K. researcher.
David Coley, a University of Bath specialist, led a team that surveyed 108 architects, engineers, and energy consultants who routinely use energy performance models. They asked participants to look at a typical British semi-detached home recently updated to meet current building codes. Then they asked test subjects to rank which improvements made the most difference to energy performance.
Their answers didn’t match up with reality, suggesting a performance gap between modeling and the real world. There were cases where the modelers produced a savings measure that was more than the energy use of the house.
Energy models showing unreasonable results are evident at the preliminary stage on half of projects going through the LEED certification process, according to a U.S. Green Building Council official. Designers have a tendency to accept outputs without evaluating the reasonability of the results, she said.
Part of the reason for the performance gap is that modelers do not usually go onsite to see how the building operates and compare that to the design. Typically there is no expectation that they’ll even talk to the building manager at year one and ask how energy usage compares with the original model.
Related Stories
| Jan 31, 2013
California Building Standards Commission adopts 2013 code update
The California Building Standards Commission adopted the new 2013 state standards code that includes new energy code provisions, accessibility standards, green building and water use modifications.
| Jan 25, 2013
D.C. authority wants to halt sewer tunnel projects while investigating green stormwater alternatives
The District of Columbia Water and Sewer Authority has proposed suspending a tunnel-building project.
| Jan 25, 2013
Energy modeling needed to overcome ‘plug load problem’ to meet high green standards
Plug loads illustrate how much end-users impact overall building energy use.
| Jan 25, 2013
ASHRAE publishes revised filtration standard, combines Standard 52.1 and 52.2
A newly revised filtration standard from ASHRAE combines two standards aimed at improving the technical accuracy of filter testing.
| Jan 25, 2013
AISC 206-13 standard for structural steel erectors available for review
AISC 206-13, a quality management system standard for structural steel erectors, is now available for public review.
| Jan 25, 2013
Builders Hardware Manufacturers Assn. revises five ANSI hardware standards
The Builders Hardware Manufacturers Association (BHMA) has released five revisions to ANSI/BHMA standards recently been approved by ANSI (American National Standards Institute).
| Jan 16, 2013
Pentagon plans huge spending cuts, including construction funds, amid budget deadlock fears
Defense Secretary Leon Panetta has ordered cuts to military spending as a precaution in case the White House and Congress fail to agree to avert $52 billion in cuts to the Pentagon budget this year.
| Jan 16, 2013
GSA's Green Proving Ground program pushes energy efficiency
The General Services Administration, which manages a portfolio of almost 10,000 buildings, is using the Green Proving Ground program to test technological advances in energy efficiency.
| Jan 16, 2013
Standards that include reflective roofs must take into account local climate
Roofs painted white can reflect heat and reduce warm-weather energy use, but in cooler regions like Minneapolis or Chicago, the issue of energy-efficiency is less straightforward.
| Jan 16, 2013
New standard for geothermal heat pump systems piping to be included in 2015 International Mechanical Code
NSF International, an independent global organization that writes standards, and tests and certifies products, has published the first in a series of American National Standards for Ground-Source Geothermal Piping Systems – NSF/ANSI 358-1.
