Green Building: It's not pretty, but it runs clean

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Anyone who thinks all green buildings are shimmering towers of glass and steel can be forgiven for that mistake. Landmarks for the movement, after all, are soaring temples of natural daylight and engineering wizardry. But experts say most U.S. commercial buildings can be turned green without spending tons of money, bringing in construction cranes or making any change that can be seen from the street.

Anyone who thinks all green buildings are shimmering towers of glass and steel can be forgiven for that mistake. Landmarks for the movement, after all, are soaring temples of natural daylight and engineering wizardry.

But experts say most U.S. commercial buildings can be turned green without spending tons of money, bringing in construction cranes or making any change that can be seen from the street.

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Consider the John Duncan Federal Building in Knoxville, Tenn. Six stories, salmon-pink facade and underground parking garage -- a ho-hum building found in almost any city.

But the 20-year-old Duncan building won Leadership in Energy and Environmental Design, or LEED, certification last year for upgrades. And there was nothing fancy or complicated about it.

Building managers replaced equipment that was at the end of its life and spent an additional $300,000 on energy- and water-saving measures that reduced the building's energy use by 33 percent and water use by 400,000 gallons a year, said Kevin Kampschroer, acting director of the General Services Administration's (GSA) Office of Federal High-Performance Green Buildings.

That it is not that difficult to green a building is potentially significant as the United States gropes for ways to conserve energy and reduce emissions of heat-trapping greenhouse gases. Buildings account for about 40 percent of total U.S. energy use, and some people say they are responsible for a similar proportion of domestic greenhouse gas. So finding easy savings is a climate priority.

GSA, which manages the Duncan building and federal buildings all across the country, reduced energy use in its building stock by 30 percent between 1985 and 2005, and is under a mandate to cut that by another 30 percent in the next 10 years.

Building efficiency is also the goal of other organizations concerned about energy issues, including the Clinton Climate Initiative and the international C40 group of large cities.

"We think it's fairly easy to gain at least 25 to 30 percent energy savings on the average commercial office building," said Gordon Holness, president-elect of the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE).

Fast results

The quickest gains can be found in commercial buildings by systematically reviewing how the existing systems for heating, air conditioning, ventilation and other basic functions work together, Holness said. Systems can get out of whack quickly, he said.

"Within a very short period of time, typically two to three years, the building is operating at a much lower efficiency" than it did when new, he said.

In large buildings, that might mean automatic settings get "temporarily" overridden and never set back. And in small structures that make up more than half of commercial building stock, he said, "I guarantee you, there's no operation and maintenance going on at all."

That means air filters quickly get dirty and air dampers get stuck. He pointed to a 1994 Texas A&M study that found between 10 and 40 percent of energy savings could commonly be obtained just by improving operational strategies.

With some spending, further gains can be made. The obvious opportunity arises when major equipment like a boiler or chiller fails, and retrofitting when the building is 20 to 30 years old can hit a sweet spot for swapping in efficient models or re-evaluating how systems work together.

GSA's Kampschroer said his agency took that approach at the Duncan building. "We found we could save a significant amount of money ... by gross-tuning the mechanical operations of the building," he said.

Heating and cooling typically represent 30 to 40 percent of the building's energy load and can yield good savings, he said. Lighting is 17 to 18 percent, and he can usually shave off nearly a third of that, partly by the familiar step of changing to more-efficient lighting such as fluorescents. Adding task lighting often helps as well, he said, in part because small lamps tap into peoples' habit to turn them off when they leave.

In some cases, more drastic steps are merited.

At the other end of the refit spectrum from the Duncan building is how GSA approached the John Kluczynski Federal Building in Chicago. Designed by Mies van der Rohe and completed in 1975, the tall black skyscraper is visible on the city skyline.

In retrofitting the building, GSA sliced up interior spaces and pulled walls away from the windows where they had been added over the years to let in more daylight. That kind of large-scale renovation is much more expensive, Kampschroer said -- on the order of $25 million -- but can yield savings that add up quickly.

In the Kluczynski case, it yields a reduction in energy use of about 60 percent.

"We're seeing it done very, very frequently in the private sector and we're doing it fairly often ourselves," Kampschroer said of the more intensive retrofit.

Tools of the trade

GSA has been aggressive in using a financial tool called an "energy savings contract" to make improvements.

Under that setup, an energy services company or utility assesses where changes can be made and estimates the paybacks that should result, then it funds the retrofit in exchange for a share of the avoided utility bills over several years.

Those tools are used in the private sector as well, said Holness, and the industry has seen significant growth recently, with big players like Johnson Controls Inc. and Honeywell International Inc. taking lead roles. ASHRAE is partway through a series of energy design guides for capitalizing on that momentum, with specific publications for everything from schools to highway lodging facilities to small warehouses and self-storage buildings.

Holness said changing existing building stock is especially important in cities. For example, 85 percent of the buildings expected to be in New York City in 2030 are already standing today.

New information technology tools can also help manage energy use. In sophisticated buildings, computers choreograph the many air and water circulation systems at work and provide a flood of real-time data to managers, Holness said.

The field has seen huge advances in the past decade, which should eventually trickle down to smaller buildings and make them easier to keep in tune.

"Over time, the cost of these systems is going to come down, just like the cost of television sets has come down," Holness said. An ongoing retrofit of ASHRAE's Atlanta headquarters is going to employ such an information technology system and post the data online for members to examine.

One challenge is coming up with performance metrics that are easy to understand.

"If I asked you how fuel efficient your car was, you could probably cite me pretty closely in terms of miles per gallon," Holness said. But building engineers talk in "British thermal units per gross square foot per year."

ASHRAE is working with U.S. EPA and the Energy Department to come up with a more intuitive energy labeling system for buildings. It could assign grades from A through F based on a structure's energy use and regional climate zone, along with a numerical score on a 100-point scale.

Despite the rapid gains that are possible, Holness expects that a wholesale transformation of commercial building stock will take decades, depending on the price of oil and, perhaps, carbon emissions. "But then again," he added, "I never would have believed the level of transformation that's happening in the auto industry in just one year."