Commissioning: In Pursuit of the Truly Green Building
Posted by Big Gav in green buildings
WorldChanging has an article on green buildings, looking at the practice of “commissioning,” in which an engineer monitors the efficiency of a building from its design through its initial operation, in order to reduce long-term energy usage by buildings - Commissioning: In Pursuit of the Truly Green Building.
In a different world, it could be a reality television show — “Buildings On Trial,” with a street-savvy engineer going into skyscrapers, factories, offices and other commercial buildings to find the dumb mistakes that make them waste energy and produce a disproportionate share of the nation’s global warming emissions.
And in almost every case, even new buildings proudly displaying a LEED “green building” plaque by the front door, the engineer would come back out with a list of energy hog culprits: Here’s the ventilation system fan installed backwards, so it blows full force into another fan blowing in the right direction. Here’s the control system set up so heating and cooling systems both work at once, like driving with your feet on the brakes and the accelerator at the same time. Here are the stuck dampers that prevent the building from drawing on outside air when the temperature is right.
Such mistakes are commonplace even in the best buildings — and often costly. In one case, says Dave Moser of Portland Energy Conservation, Inc., an Oregon nonprofit, it cost a building owner $5,000 to fix stuck dampers — and cut $50,000 off the annual energy bill. In a case of simultaneous heating and cooling at an 85,000-square-foot academic building, a minor programming fix cost almost nothing and saved $100,000 a year in wasted energy, according to Mark Miller of Strategic Building Solutions, a Connecticut company.
The business of finding and fixing these mistakes is called “building commissioning,” a term borrowed from the standard naval practice of commissioning a new ship with sea trials to determine whether it’s fit for service. People started doing roughly the same thing with non-residential real estate in the mid-1990s, as buildings with computer-controlled systems became almost as complex as ships at sea. Commissioning frequently involves no more than a few weeks of testing out systems. But in the most complete form, the commissioning agent works with architects in the design stage, to help save money by specifying properly sized energy systems, then follows the building through construction, trains the operating staff, and tracks energy performance in different seasons through the first year of operation. Older buildings now also go through retro-commissioning, in search of improved efficiency.
But if you imagine that real estate developers must be lining up for this service — if only to save money, or determine whether they are getting the building they paid for — you would be mistaken. Even now, well under 5 percent — and probably closer to 1 percent — of new commercial buildings actually go through the process. Projects seeking certification under the Leadership in Energy and Environmental Design (or LEED) program, managed by the U.S. Green Building Council, can earn extra points by going through “enhanced” commissioning. But they’re only required to do “fundamental” commissioning — a sort of commissioning-lite, potentially performed not by a third party, but by an “independent” employee of the construction manager whose contractors made the mistakes in the first place.
And yet building commissioning is “arguably the single-most cost-effective strategy for reducing energy, costs, and greenhouse gas emissions in buildings today,” according to a 2009 report from Lawrence Berkeley National Laboratory. If applied to the nation’s entire non-residential building stock, including retro-commissioning of older buildings, it would yield $30 billion in potential energy savings every year by 2030, the study projects, and avoid 340 million tons of global warming emissions annually. To put the latter number in perspective, other studies project that the United States is now on a path to increase global warming emissions by more than a third, up to 9.7 billion metric tons a year by 2030. Roughly 35 percent of emissions come from heating, cooling, and providing electric power for buildings and homes, split evenly between commercial and residential. So building commissioning is hardly the only remedy required. But the potential savings ought to make it one of the most attractive.
Why isn’t it more popular? A lot of developers, and even some building efficiency experts, have simply never heard of commissioning. Others have gotten turned off, says Glenn Hansen of Portland Energy Conservation, Inc., by early experiences in which “a fairly junior engineer” would go through a building checking off boxes on a clipboard. In a 2008 study by the New Buildings Institute, the energy performance in many LEED-certified “green” buildings was actually worse than in the average conventional building, probably because inexperienced people doing “fundamental” conditioning had failed to detect problems.