Steven Glenn of Santa Monica lives in "the greenest house on the planet," BusinessWeek says. Which sounds exciting -- except Amory Lovins of the Rocky Mountain Institute also lives in "what may be the greenest house on the planet," as this video put it.
Lovins has no furnace and pays nothing to heat his home high in the mountains of Colorado, where temperatures can reach minus-40 degrees; yet super insulation and high-performance windows help make it warm enough for him to grow bananas.
So which home is greenest?
- Ann and Gord Baird, who live in "the greenest modern home in the world," as named by the Cascadia Green Building Council.
- David Gottfried, whose renovated 1915 Craftsman bungalow has been called "the greenest house in America," (fitting, perhaps, considering that he co-founded the U.S. Green Building Council, whose LEED rating system has become the nation's dominant rater of green buildings).
- A California couple, whom The Atlantic magazine has featured in their quest to build "the world's greenest home" -- a five-bedroom, 5,600-square-foot house with solar panels strong enough to charge five electric cars, power the house and return energy to the grid.
You get the idea. And the list goes on. There's even a TV series on the topic. So which home really is the most environmentally friendly, and what's fueling the competition anyway?
"It's pure marketing speak," says James S. Russell, a fellow of the American Institute of Architects, architecture critic for Bloomberg News and author of the forthcoming book, The Agile City. "There's a lot of different ways to define what makes something the greenest. There's really no consensus on that. I think to say you're the "greenest" -- it's marketing, but not much else."
"We seem to have a need in this country to compete about everything," says Tristan Roberts, editorial director of the independent publishing company BuildingGreen.com, which specializes in unbiased green-design information. "Who's got the greenest home has certainly become one of those areas."
If battling for eco-habitation bragging rights helps motivate people toward a lower environmental impact, "then I'm all for it," says Roberts. Yet, he cautions, it sometimes leads to claims "that might not be completely valid or true from all angles."
Nate Kredich, vice president of residential market development for the U.S. Green Building Council, says the trend is a positive signal that "consumers are becoming increasingly aware that we all should be living in green homes.
"We love seeing people pushing the envelope in residential sustainability," Kredich says. "In many ways, it ends up being an impossibly subjective competition, since there are so many elements of a green home. Which is greener: a home made entirely of natural and sustainable materials or another one that puts power back on the grid?"
We still don't have an answer: Which home really is the greenest on the planet?
Kredich of the Green Building Council said his organization doesn't offer a definition of the 'world's greenest home.' " The council's LEED rating system assigns points for a long menu of features and the more points a building racks up, the better. The greenest homes under this system get a "LEED Platinum" rating; so far, that certification has been given to more than 2,100 homes.
The bottom line: Single-family homes (like the Greentown Silo Eco-Home, above, in Greensburg, Kan.) are out. "The quickest way to get to green is to live in an apartment," says Russell, the NYC architecture critic. The walls you share with other tenants "automatically reduces your energy use just right off the bat."
Single-family homes are problematic, especially if they house just two people far from work and commerce, requiring many miles of car travel. A big house requires lots of products, no matter how green. "But I never want to say people can't have those lifestyles," Russell says. "I think they certainly can't call them 'the greenest.' "
Roberts' definition of a green home starts with a small size, which means fewer materials to build it, a smaller place to heat and light. He notes that the average home built today is 2,500 square feet, "which is big. If you go back 50 years in this country, it's doubled in size, on average."
Trophy green homes and eco-McMansions are way larger. "You have to wonder: Was that really necessary? Does that really define green?" Roberts says.
Solar panels and other features let some trendy houses produce enough of their own energy that they actually sell power back to the energy company, which is nifty. Yet a person vying to live in the world's "greenest" house could theoretically load it up with big-screen TVs and other less-than-efficient appliances, then write a mega-check to put solar panels all over the roof. But the resources consumed would belie the "green" label.
"You can get to net-zero just by writing a check," notes Roberts. "There's something a little off about that."
It's better, Roberts says, to focus on what lots of people can do:
- Hire an energy auditor to see where your place is leaking energy.
- Change your lightbulbs to compact fluorescents or LED lighting.
- Get as much insulation as you can.
- Live in a well-designed, modestly sized home.
- Have a very efficient heating and cooling system.
- Buy electricity-sipping appliances.
"If everyone went out and did that," he says, "then we'd have a country of green homes instead of a sprinkling of 'greenest' homes."
In the end, the world's greenest home, Roberts says, very likely is: a) not in North America, Europe or industrialized parts of Asia; b) not advertised as "the greenest" because the person living there isn't thinking about that; c) probably very modest in size, relative to square footage per person, and probably uses natural materials and a vernacular design instead of being a so-called "international style" of building; d) probably in a rural area.
"They're just living probably a very modest simple life," Roberts says, "that doesn't have a big footprint."
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