The rise of green buildings

The author of today's post, Andy Darrell, is Regional Director for the Living Cities program at Environmental Defense.

In 1800, 3 percent of the world's people lived in urban areas. In the last year, that number is likely to have passed 50 percent [PDF]. The world is becoming urbanized at an extremely fast rate, and as the urban population increases, so does urban development.

This presents an opportunity in the fight against global warming, since energy use in buildings accounts for 40 percent of greenhouse gas emissions in the U.S.

You might think it costs a lot more to make a building energy efficient, but it doesn't have to. A building that produces half the usual emissions can cost as little as 1 percent more to build. How can that be?

Green buildings can be cost effective because payback is not only in future energy use. For example, if you spend more on high insulation windows, you may be able to save money with a smaller furnace.

Green buildings are going up all over the world:

• Federal Building, San Francisco - 50 percent less energy use than standard office towers.
• Bank of America Tower, NYC - planned LEED Platinum certification.
• Pearl River Tower, Guangzhou, China - net energy footprint of zero.
• Le Phare (The Lighthouse), Paris, France - powered by wind turbines.

But it's not all about new construction. Retrofitting existing buildings is just as important as making new buildings energy efficient.

New York City's PlaNYC, a plan for managing the city's growth through 2030, says that while new construction is one focus area, "We have focused primarily on upgrades to existing buildings, since they will still form the overwhelming majority of our building stock by 2030." "[R]eplacing outdated lighting systems with more energy-efficient models" and "improved[d] standards for appliances and electronics … can achieve enormous savings" in usage and energy bills.

The renovation of the U.N. building, scheduled for completion in 2014, is a case in point. The revamped building will look the same as it always has, but its energy bill, which was $30 million in 2004, will be at least 40 percent lower.

How do you make a building green? Well, it depends on where it is. If it's a place that gets a lot of sun, solar energy might work. If it's a windy locale, wind turbines might be the better choice. Glass, no glass, windows facing the sun or not - these are all decisions that depend on the environment in which you're building. Standard buildings impose their artificially created climate on their environment. Green buildings work with the environment, rather than fighting against it.

You can learn more about sustainable urban development in Environmental Defense's Green Renaissance [PDF] report, which gives detailed descriptions of green buildings in New York City.