Glass and water may seem like strange building materials to highlight in modern construction but they are key factors in the energy efficiency of the 12-story, million-square-foot North American headquarters being constructed in Stamford, Conn., for the Royal Bank of Scotland under so-called green building principles..
Those simple ingredients are part of a trend toward nonfossil fuel heating and cooling options in cities like Stamford and throughout the Hudson Valley and Westchester County, where down-home items like wood pellets are being used in modern boilers to increase heating efficiency and reduce pollution, or where geothermal systems are heating and cooling via the Earth itself.   Â
The trend toward energy efficiency and cleaner heating and cooling options for buildings is no fad, say architects working in the field. “I think it”™s fair to characterize it as a corner that”™s been turned,” said Brad Will, president and CEO of Ashokan Architecture and Planning PLCC of Kingston. “People realize we have to be much better stewards of our urban and rural lands.”
Architect Roger Ferris of Ferris and Partners of Westport, Conn., said that in hiring his firm to design its $500 million building, RBS officials explicitly sought a progressive design. “We”™re just catching up here in America,” said Ferris. “The sustainable movement is much more advanced, progressive and sophisticated and respected in Europe than it is here. RBS had expertise and knew they wanted to have a very energy efficient sustainable building.” He said when the RBS building opens in mid-2009, it will use less energy than structures that are only 20 percent as large.
The U.S. Green Building Council offers LEEDS (Leadership in Energy and Environmental Design) rankings based on points accrued in a building design and construction, awarding either silver, gold or platinum. Ferris said that the RBS building will likely fall just short of the coveted platinum standard, but be plenty green with a gold LEEDS ranking.
He said the design starts with water. The RBS building will house a one-acre garden on the open terrace on the eighth floor of the J shaped building which will capture and decontaminate rainwater, using the plantings on the building as bio-filters. Then the water is repeatedly circulated throughout the building as a coolant. He said the complex contains large capacity water storage tanks so that there will be plenty of water to serve the needs of the building, even when rain is scarce. And he said the system will not need to draw on the groundwater or on Stamford”™s city water supply, thus preserving that resource.
And glass will also serve as a key energy component, with the horizontal design favored in Europe utilized instead of the vertical skyscraper design common in American cities. A horizontal and relatively narrow structure allows for greater use of natural light to illuminate the interior areas instead of requiring high energy office lighting fixtures. “We want natural day lighting to provide most of the light that is why windows are from floor to ceiling,” said Ferris. “Its a substantial sustainable aspect of the building.”
Glass also lets in the sun, which could serve to heat the interior of the building, a fact Ferris is keenly aware of in designing the system. “Everything is a balancing act in architecture,” Ferris said. Thus to maintain the gain glass allows in reducing energy needs from lighting, high tech glass is used. The glass contains gas that reacts to sunlight to reduce its solar heating, and is complemented by computer controlled blinds that automatically adjust to the angle of the sun and deflect the harshest and hottest rays while allowing light to permeate the interior. And then in the winter, the blinds and gases are not needed and the solar rays are allowed to penetrate to help warm the interior.
“In this part of the country we have six or seven months where we want that heat gain and we have a mechanical system that captures the heat and spreads it though the building,” said Ferris.    Â
Like glass, wood is another material not often associated with efficient modern energy and heating, yet in certain areas, wood pellets are the most economically and environmentally sound method for heating even large buildings, said Will of Ashokan Architecture. He said the new pressed pellets combined with using modern ultra-efficient boilers essentially vaporize the wood to capture an extremely high amount of heat while sending almost no particulates or pollution into the atmosphere.     Â
“Compared to say burning a log, it”™s a different delivery system altogether; it”™s very efficient and it”™s an idea that is gaining traction,” said Will. “There is a whole new generation of boilers out there.” He said like most efficiency technologies, pellet burning can be “scaled” to meet the needs of small businesses or large institutions and described one user with several boilers fed by a single silo of pellets with the heat piped to multiple buildings.Â
Geothermal heating, where wells and pipes reach the ground water that is at a constant roughly 50-degree temperature, is another option rapidly gaining adherents. Will said the system is most affordable in places where there is room for a well on the property but said wells can even be dug through the bottom of a building, albeit more expensively. Â
Will and Ferris both extolled the value of common sense in construction or renovations. Techniques as simple as allowing south facing surfaces to absorb solar heat in the winter, and using light covered roofing material to reflect sunlight in summer create energy efficiencies without using costly power. A tight building envelope that holds in heat in the winter or keeps cool air inside in summer is a basic idea that is too often overlooked.
Another important contribution to efficiency: appliances and other electrical products. Ferris said that the RBS building budget will pay for the most efficient motors and machinery to run the building mechanisms. Such efficient machinery often cost more up front, and though he said there is a pay back over a decade or more, he said that is not the reason for buying energy-smart appliances and fixtures.
“You pay the premium because you”™re providing a more responsibly designed environmentally sound building,” said Ferris. “It”™s our mandate. It”™s everybody”™s mandate to set the bar that high and climb the ladder.”
“In the past, it was always, what”™s the payback?” said Ferris. “The payback is we”™re all going to have fresher water and cleaner air and we”™re not going to run out of fuel. Is that a good enough payback?”Â
