Dear EarthTalk: Do insulating paints actually insulate and save energy? If they do, are they environmentally friendly to use?
—Bob Dibrindisi, Easthampton, MA
Paint additives that claim insulating qualities have been marketed since the late 1990s, but energy research organizations have not confirmed their insulating value. For its part, the U.S. Environmental Protection Agency (EPA) does not recommend using paints or coatings in place of traditional bulk insulation. "We haven't seen any independent studies that can verify their insulating qualities," the agency reports. The federal government does rate roofing paint for its energy efficiency, but such findings only take into account a substance's ability to reflect heat off the roof—not its insulating properties per se—to keep the building cooler.
According to the Department of Energy's Oak Ridge National Laboratory, the use of so-called insulated paints is in most cases "difficult to justify on the basis of savings in energy costs alone." Meanwhile, the non-profit EnergyIdeas Clearinghouse, a partnership between Washington State University and the nonprofit Northwest Energy Efficiency Alliance, found that under ideal circumstances insulating paints can achieve a "reduction in heat gain" of around 20 percent on freshly-painted sun-exposed walls, but notes that such walls will only face direct sunlight for a limited part of even the clearest summer day. Also, the clearinghouse reports that "heat gain reductions
are significant only for sun-bathed surfaces" and that the "reflectivity of the painted surface generally declines considerably with time."
Alex Wilson of the website BuildingGreen.com is not a fan of insulating paints: “To say that there is a lot of hype about insulating paints
is an understatement," he tells the website Treehugger.com. "The Internet is rife with claims of paints that dramatically reduce heat transfer—usually based on some technological magic spun off from NASA. While these products may have some relevance in the extreme conditions of outer space, manufacturers of paints containing [insulating additives] are making claims that defy the laws of physics
when they claim they can save significant energy in buildings.”
Nevertheless, for certain applications, especially in concert with traditional forms of insulation underneath, insulating paint can help reduce energy expenditures and air conditioning bills accordingly. For those who want to forge ahead with insulating paint despite the limited benefits, some of the leading brands to look for include Insuladd, Hy-Tech, Therma-Guard and Eagle Coatings" SuperTherm.
Adding insulating paint should merely be the icing on the cake of an otherwise well-conceived plan to cut heating and cooling costs. Installing a traditional form of insulation would be the first defense. A reflective, radiant barrier on the roof structure in the attic also could offer significant help, according to the Florida Solar Energy Center. Thermal-pane windows and energy-conscious practices will contribute to the effort. Finally, consider trees and other landscape shading, which the U.S. Department of Energy recommends as an effective way of passively cooling your home. For more ideas, visit the "do-it-yourself energy audit tool" on the Lawrence Berkeley National Laboratory's Home Energy Saver website.
Dear EarthTalk: As I understand it, "clean" coal really isn"t—yet the Bush Administration gushed strongly for it. What is Obama's take on it?
—John Zippert, Eutaw, AL
Barack Obama and George W. Bush differ in many ways, but both have embraced so-called "clean coal" for providing an ongoing supply of cheap and readily available energy for electricity generation.
The term "clean coal" is loosely defined as coal that is washed or processed to remove pollutants, so as to reduce emissions of carbon dioxide (CO2), the leading greenhouse gas, when the coal is burned. Coal-burning plants emit 40 percent of U.S. CO2 pollution—half of our electricity comes from coal—so reducing the industry's carbon footprint in any way possible would be a big win for the environment.
Luckily for clean coal advocates, the White House has been and continues to push for its development. George W. Bush's support for clean coal dates back to his first term in office, when he stated that such technologies should be encouraged as a means of reducing dependence on foreign oil. And since taking office, the Obama administration has committed $3.4 billion in stimulus dollars to clean coal projects.
But green groups continue to question the wisdom of relying on coal at all. Coal wreaks environmental havoc, from the coal mines that pollute rivers and streams, to the premature deaths of coal miners from accidents and lung diseases, to the release of greenhouse gases, mercury and other toxins at power plants.
According to Greenpeace, burning coal emits 29 percent more CO2 than does burning oil or natural gas. And coal-fired power plants are the world's largest sources of atmospheric mercury, a known neurotoxin that disperses quickly throughout the environment and into the food chain. Greenpeace says that clean coal technologies will not address this problem, and that there are "no commercially available technologies to prevent mercury emissions from coal-fired power plants." Also, the group says, clean coal will do nothing to mitigate coal mining's damage to wildlife habitat and drinking water sources.
"There is no such thing as "clean coal" and there never will be," Dan Becker of the Sierra Club told the Grist.org website. "It's an oxymoron." The Reality Coalition, a group of nonprofits that includes the Sierra Club, has been running TV ads seeking to debunk industry claims that coal can be clean. Green groups also worry that pushing clean coal will only delay the transition to a truly cleaner and greener energy infrastructure based on solar, wind and other emissions-free renewable energy sources.
In April of 2009, environmental lawyer Robert F. Kennedy, Jr. questioned the motivations of Obama and other politicians who back clean coal. "The coal industry and the carbon industry in general are the largest contributors to the political process," Kennedy told ABC News. "You don't have politicians representing the American public, but rather the people who finance their campaigns."
Of course, Obama's support for clean coal doesn't negate the fact that he has proposed spending much more on further development of alternative energy sources. He has called for getting 10 percent of U.S. electricity from renewable sources by 2012 and 25 percent by 2025, and has committed upwards of $32 billion of stimulus dollar
s to the cause, according to an analysis by the nonprofit Environment America.
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