sustainability

The prospect of generating pollution-free power from the sun’s rays is appealing, but to-date the low price of oil combined with the high costs of developing new technology have prevented the widespread adoption of solar power in the U.S. and beyond. At a current cost of 25 to 50 cents per kilowatt-hour, solar power costs as much as five times more than conventional fossil fuel based electricity. And dwindling supplies of polysilicon, the element found in traditional photovoltaic cells, are not helping.

According to Gary Gerber of the Berkeley, California-based Sun Light & Power, not long after Ronald Reagan moved into the White House in 1980 and removed the solar collectors from the roof that Jimmy Carter had installed, tax credits for solar development disappeared and the industry plunged “over a cliff.”

Federal spending on solar energy picked up under the Clinton administration, but trailed off again once George W. Bush took office. But growing climate change worries and high oil prices have forced the Bush administration to reconsider its stance on alternatives like solar, and the White House has proposed $148 million for solar energy development in 2007, up almost 80 percent from what it invested in 2006.

In the realm of research and development, enterprising engineers are working hard to get solar power’s costs down, and expect it to be price-competitive with fossil fuels within 20 years. One technological innovator is California-based Nanosolar, which replaces the silicon used to absorb sunlight and convert it into electricity with a thin film of copper, indium, gallium and selenium (CIGS). Says Nanosolar’s Martin Roscheisen, CIGS-based cells are flexible and more durable, making them easier to install in a wide range of applications. Roscheisen expects he will be able to build a 400-megawatt electricity plant for about a tenth of the price of a comparable silicon-based plant. Other companies making waves with CIGS-based solar cells include New York’s DayStar Technologies and California’s Miasol .

Another recent innovation in solar power is the co-called “spray-on” cell, such as those made by Massachusetts’ Konarka. Like paint, the composite can be sprayed on to other materials, where it can harness the sun’s infrared rays to power cell phones and other portable or wireless devices. Some analysts think spray-on cells could become five times more efficient than the current photovoltaic standard.

Environmentalists and mechanical engineers aren’t the only ones bullish on solar these days. According to the Cleantech Venture Network, a forum of investors interested in clean renewable energy, venture capitalists poured some $100 million into solar start-ups of all sizes in 2006 alone, and expect to commit even more money in 2007. Given the venture capital community’s interest in relatively short-term returns, it’s a good bet that some of today’s promising solar start-ups will be tomorrow’s energy behemoths.

For more information
• Sun Light & Power
• Nanosolar
• DayStar Technologies
• Miasol
• PowerFilm
• Konarka

Dear EarthTalk: Do buildings with various “green” features cost more to build and operate than traditional buildings?

It is difficult to do an apples-to-apples cost comparison of a “green” structure against one that is not due to differences in design, materials and other factors, including the location. But the general consensus is that a green building might well cost slightly more up front, but it will very likely reap the rewards of lower operating costs going forward.

The U.S. Green Building Council’s Leadership in Energy and Environmental Design (LEED) program is the standard-bearer used today in evaluating the relative green-friendliness of building projects. A 2004 nationwide study conducted by Greg Kats of the research and consulting firm Capital E found that structures that qualified for the lowest LEED rating (“LEED Certified”) cost builders less than one percent more up-front than equivalent non-green buildings. For projects with more ambitious green features that qualified for higher LEED ratings (silver, gold and the highest, platinum), the cost premiums went up from between 1.9 percent and 6.8 percent, still surprisingly low.

What surprised Kats even more, though, was the value of the payback. Overall, Kats found that the average cost premium for building green was about $4-5 per square foot, while the financial benefits derived over 20 years from incorporating sustainability features—such as lower energy and water bills—was in the range of $49-65 per square foot, or about 10 times the value of the initial investment. Another 2004 study by Lisa Matthiessen of the consulting firm Davis Langdon came to similar conclusions. According to Matthiessen, incorporating sustainability elements in a project’s design from the get-go—not layering them on later in the process—is essential to keeping the costs down.
Despite these financial benefits, Kats points out that there is unfortunately a “consistent disconnect” in peoples’ minds between the higher up-front costs of building green and the ensuing savings in operating costs. He says that overcoming this is fundamental to understanding the value of green building.

And, of course, money is not the only issue. Transitioning to a greener built environment is important for the conservation of natural resources as well as for reducing pollution. According to statistics gathered by the U.S. Green Building Council, the 76 million residential and five million commercial buildings in the U.S. collectively consume 65 percent of America’s electricity, 37 percent of its energy, 25 percent of its water supplies and 30 percent of its wood and materials. Likewise, buildings account for 35 percent of the nation’s solid waste, 36 percent of carbon dioxide emissions, 46 percent of sulfur dioxide emissions, 19 percent of nitrous oxide emissions and 10 percent of fine particulate emissions.

Sustainable buildings, such as those that qualify for LEED certification, consume fewer resources, generate less waste, cost less to operate and provide healthier living and working environments for everyone—both indoors and out.

For more information
• U.S. Green Building Council, www.usgbc.org; Capital E’s “Green Building Costs and Financial Benefits,” www.cap-e.com/ewebeditpro/items/O59F3481.pdf.

Got an environmental question? Send it to: EarthTalk, c/o E/The Environmental Magazine, P.O. Box 5098, Westport, CT 06881; submit it at: www.emagazine.com/earthtalk/, or e-mail: earthtalk@emagazine.com. Read past columns at: www.emagazine.com/earthtalk/archives.php