Green buildings have saved the U.S. billions of gallons of water and enough energy to avoid the equivalent of burning of 1.3 million tons of coal for electricity since the development of the LEED standards.

In the process, these high-performance buildings have produced millions of dollars in employee productivity gains, avoided thousands of tons of soil erosion, and created a multibillion dollar market for the green building materials used in their construction.

Yet all of this still isn't enough to overcome global climate change, according to the Green Building Impact Report 2008, which was written by GreenerBuildings.com Executive Editor Rob Watson and released Wednesday in Boston at Greenbuild, the U.S. Green Building Council's annual conference.

The report is billed as the first to comprehensively gauge whether LEED buildings are producing real and verifiable environmental improvement as promised. Though LEED buildings are reducing individual site impacts, market penetration must significantly escalate to truly move the needle forward, it found.

"Our findings are both encouraging and cautionary," Watson said as part of the report's release. "Overall, we believe that LEED buildings are making a major impact in reducing the overall environmental footprint of individual structures. However, significant additional progress is possible and indeed necessary on both the individual building level and in terms of market penetration if LEED is to contribute in meaningful way to reducing the environmental footprint of buildings in the U.S. and worldwide."

The report chronicles LEED's growth in an industry where buildings consume about 40 percent of the world's energy and contribute roughly a quarter of global greenhouse gas emissions. LEED registrations and certifications doubled in 2007, compared to the previous six years, and doubled again in 2008 relative to the previous seven years.

Watson foresees a slowdown and eventual flattening of the rates in the U.S. because of the faltering economy and increasing rigor of LEED requirements. Yet growth overseas will continue adding LEED floor space at a pace that could surpass that of the U.S.. The 295 million square feet of LEED-certified floor space existing today in the U.S. could balloon to 5.6 billion square feet by 2015, and to 11.1 billion by 2020.

You can download the Green Building Impact Report from GreenerBuildings.com
GBIR 2008 cover

The reduced environmental impacts from LEED buildings cited in the report are heartening. LEED buildings, for example, operate on about a quarter less energy than their conventional counterparts and have so far prevented the burning of about 1.3 million tons of coal for electricity. By 2015, that figure could hit nearly 26 millions of tons of coal we won't have to tap for electricity, and nearly 49 million tons of coal by 2020.

LEED buildings have saved the U.S. 9.5 billion gallons of water, an amount that could surpass 133 billion gallons by 2015. Water savings could double again by 2020.

LEED buildings present a strong business case for the dollars they can not only generate, but also save for their occupants. LEED building occupants, for instance, have driven nearly 400 million fewer miles since 2004, and occupants may drive more than 4 billion fewer miles by 2020. Employee productivity could grow from $170 million annually now to nearly $2 billion by 2020. The current $10.5 billion green materials market could also grow to more than $100 billion over the next 12 years.

The report calculates that carbon dioxide emissions from commercial buildings in the U.S. must drop 1.6 percent every year to meet an overarching goal of reducing emissions 80 percent by 2050 to avoid the worst effects of climate change. LEED buildings are now exceeding that target, but the rest of the entire building sector isn't.