In the building trades, green is the color of choice these days. With an increasing public focus on issues like climate change, building designers are touting energy efficiency and lower “carbon footprints” as a key point in favor of new construction.

But newer doesn’t always mean greener. When it comes to green buildings, the story is more complicated than you might think.

That was certainly the discovery of a team of Forest Service engineers, when they were tasked with calculating the energy consumption of the agency’s buildings on the Superior National Forest.

The Forest Service, like many federal agencies, is under direction to improve the efficiency of federally-owned buildings— and that push for improved efficiency is prompting federal agencies in some cases to abandon older buildings in favor of new and presumably greener buildings.

But as recent studies have demonstrated, even buildings certified for their green design (a certification known as Leadership in Environmental and Energy Design, or LEED) often aren’t as energy efficient as promised.

Take the case of the Forest Service’s new headquarters on the Kawishiwi Ranger District, in Ely, the first building on the Superior to obtain a LEED-Silver certification.

“It’s a real nice building,” said Forest Service engineer Art Johnston, who worked on the analysis of the energy efficiency of federal buildings on the forest, “but it didn’t meet our energy objectives.”

In fact, the results of the 2009 analysis of building efficiency came as a shock to Forest Service officials. Of the seven headquarters buildings examined, the brand new Kawishiwi headquarters was the least energy efficient per square foot and had the third-highest carbon footprint. “It has been surprising and a little bit worrisome,” said Johnston. “If we’re building these new facilities and they aren’t that efficient, it takes away the incentive to replace old buildings,” he said.

Johnston notes that the energy analysis was done shortly after the Kawishiwi headquarters opened, and he said the energy usage has been reduced since then as the agency has fine-tuned its operation. In fact, according to Kawishiwi District Ranger Mark Van Every, the building’s propane usage has been cut from almost 16,000 gallons in its first year of operation, to 12,600 gallons the following year.

Still, says Johnston, “it’s not an energy efficient building.”

The Kawishiwi example, it turns out, is not an isolated case. Recent studies that examined the energy efficiency of LEED-certified buildings have found that while many perform well from an energy perspective, a surprisingly large percentage perform no better than average for existing commercial building stock, and some perform worse.

According to Environmental Building News, a recent study from Massachusetts found that, on average, LEED-certified buildings examined in that state performed substantially worse (40 percent worse) than predicted by energy modeling developed prior to construction.

A study by the Green Building Council, which analyzed the energy use of 121 new LEED-certified buildings in 2006, found that 53 percent did not qualify for the Energy Star label, a prominent standard for energy efficiency developed by the Environmental Protection Agency. In addition, 15 percent scored below 30 in the Energy Star rating system, meaning they used more energy per square foot than at least 70 percent of comparable existing buildings across the country.

Such surprising results have led LEED officials to consider moving towards the Energy Star model, which would require LEED buildings to be re-certified as meeting energy efficiency goals on an annual basis.

Why aren’t new buildings more energy efficient?

Johnston said one of the factors that seems to be reducing energy efficiency in newer buildings is the amount of fresh air that is now required by most building codes. While increasing the flow of outside air makes buildings healthier for occupants, Johnston said it can come at a price.

Many modern buildings use heat exchangers, which recapture some of the heat from inside air before it is vented outside. But such systems, which rely on large fans to move a high volume of air, can consume a surprising amount of electricity, which adds to a building’s energy demands and its carbon footprint. Johnston has calculated that every kilowatt-hour of electricity generated in northeastern Minnesota (a region largely dependent on coal-generated power) creates about 1.8 pounds of carbon dioxide, a greenhouse gas. And with large fans that run almost continuously for heat exchange in many “green” buildings, the environmental costs can be surprisingly high.

“You find out that it can take more energy to operate than you actually save,” said Johnston. “Depending on your heating source, you’d be better off opening your window for fresh air,” he said.

In too many cases, worries Johnston, building designers are relying too heavily on high-tech equipment that can be inefficient if not maintained for peak performance. He said a focus on sensible operations can yield big energy savings, even in older buildings.

A case in point is the Superior’s main office in Duluth (known as the Supervisor’s Office, or SO), located in a former school building built decades ago.

For years, it was a heavy energy consumer, in part, says Johnston, because the building’s mechanical system was not set up properly. In one part of the building, he discovered a large duct heater that operated around-the-clock, and that drew 10,000 watts continuously. Shutting it off reduced the SO’s total electrical usage by a whopping 7-10 percent, without affecting the comfort of occupants.

At the same time, through interior retrofitting to add insulation, and daily monitoring of energy usage, the Forest Service has made significant progress in reducing its carbon footprint at the SO.

“It’s simple things, really,” said Jim Sanders, Superior Forest Supervisor. “If you look at the carbon reduction, we had a 49 percent reduction here, and this is an old building and it was achieved at minimal expense.”

According to Sanders, timers were installed on building thermostats, coffee makers, copiers, and pop machines, so energy consumption was cut dramatically at nights and on weekends. Officials replaced older computers and monitors with newer, more efficient models, which also helped cut energy usage. “It’s actually fun,” said Sanders. “It’s also a challenge and now what we’ve learned here, we’ve continued across the other districts.”

The energy improvements at the SO were achieved because the occupants essentially took ownership of their energy usage, and put someone in charge of the task. Johnston said that’s not the case for many large buildings, and that means inefficient operations can continue, often for years. He said it’s not uncommon in large buildings to find air cooling and air heating systems operating simultaneously, and needlessly wasting energy.

“Buildings don’t save energy by themselves,” said Johnston. “But if you pay attention and operate it wisely, you can really find some savings.”

That’s equally true at the Kawishiwi office, notes Sanders. “We’re still fine-tuning in Ely,” he said. “It takes time to understand these systems. The HVAC systems, you really have to learn how to run them. The potential is there, but it takes a while to really get the efficiencies out of it.”

Other ways to be green

Van Every notes that many other factors need to be considered when determining how green a building actually is. “The construction materials are another consideration,” he said. “Getting materials from nearby matters. We purchased many of the supplies from northeastern Minnesota.”

The siding, for example, was milled near Grand Rapids, while decorative rock came from a local quarry. Rock removed during site preparation became part of the building’s landscaping, and even the interior wainscoting is a paperboard product manufactured from recycled newspapers. A display in the building’s visitors’ area shows many of the other efforts to utilize local and recycled products in the building’s construction.

Even the location of the building was designed to be more efficient, according to Van Every. “Being right on the Trezona Trail, allows more workers to commute by bike,” he said. “A lot of employees appreciate that.”

And the efficiency of any operation, said Van Every, needs to be compared with what existed before construction of any new building. “Now, we’re all in one building, rather than the three sites we had in the past,” he said. “The old office was not energy efficient,” said Van Every. “And it was not a comfortable environment at all.”