黑洞社区

The world鈥檚 largest new green building, the 3,000-room, $1.9bn Palazzo Resort in Las Vegas received its LEED Silver rating and certificate in March.

The huge resort is more than four times bigger than any other LEED-certified building, according to the US Green 黑洞社区 Council, which presented developer Las Vegas Sands Corporation with a LEED plaque at a recent awards ceremony. Coming soon, the Las Vegas City Centre project, when completed in 2009, will boast the largest development of LEED Silver-certified projects, some 17 million ft虏 (1.58 million ft虏), representing some $7bn of investment. If you鈥檝e been there, you know that everything in Las Vegas is on grand scale, now even green buildings.

LEED project registrations topped 10,000 commercial and institutional buildings in March 2008 for the first time. New construction and major renovation projects represent about 80% of all new LEED projects, the balance coming from tenant remodels and existing building operations. In the certification derby, there are now about 1,325 fully certified projects, roughly equal to the BREEAM total in the UK (though in fairness, the BREEAM project certifications represent a much higher percentage of total construction, owing to the fivefold population difference between the two countries.)

LEED for Homes dwelling unit registrations topped 10,000 for the first time, though only about 5% of these projects have been certified to date. There is a hot race on between LEED and the National Association of Home Builders certification systems to emerge on top, though the current leader is in fact the national government鈥檚 ENERGY STAR program, which certified more than 130,000 homes in 2007 for their energy and indoor air quality characteristics. Other contenders include General Electric鈥檚 鈥淓nvironments for Living鈥� program and a number of well established local and regional certification programs.

President takes a green turn

Big news in the US this week was president George W. Bush鈥檚 announcement that the country should begin taking steps to reduce the growth in greenhouse gas emissions to zero by 2025, sometime in the third Clinton Administration (counting the couple鈥檚 daughter Chelsea, who will be old enough to run for president in about the 2024 election). This is akin to a sinner agreeing to give up something for Lent in a dozen years or so, not nearly enough to have any discernible effect on salvation. Waiting until 2025 to stop growing GHG emissions is a bit like rearranging the deck chairs on the Titanic as it鈥檚 sinking, isn鈥檛 it?

The good news on GHG emissions growth is that no one is waiting around for the US federal government to enact mandates on either the power industry or the auto industry. Companies of all stripes are aggressively moving toward zero net carbon emissions. I鈥檒l wager that you鈥檒l begin to see a large number of 鈥渘et zero鈥� GHG emission buildings going up in the US in the next two to four years, with the first generation of 鈥渞egenerative鈥� buildings following soon after that. Retail giant Wal-Mart announced this week the roll-out of its new generation 鈥淗E-5鈥� high-efficiency prototype store for the Western US climates, promising to reduce energy use a whopping 45% over its current stores. We鈥檒l see the first 鈥渘et zero鈥� energy retail stores, I鈥檓 sure, by 2010, both in the US and in the UK.

Finally, I鈥檇 like to relate a little from my attendance at the 12th Passiv Haus conference in Nuremberg, Germany, last week. The German Passive House concept shows clearly how to reduce energy use in housing by 90% without sacrificing comfort, health or safety. In fact, comfort is increased because those nasty draughts that ventilate most homes just disappear, replaced by a well modulated fresh-air intake via a whole-house heat recovery ventilator.

Windows are so well insulated that the temperate difference between the center of the room and the window surface is about two to three degrees Kelvin (Celsius), even when outdoor temperatures are minus five or more. The net cost add-on is about 2%, pretty much in the noise level for home building. Looks like Code 6 zero net energy housing in the UK could be quite feasible by 2016, with only 10% on-site renewables. There was a considerable UK and Irish contingent at the conference, most notably leading a rousing Friday evening banquet sing-along of 鈥淪weet Molly Malone.鈥�