Think globally, act locally, save moneyOne of the simplest ways to save energy and money is to have a light colored roof. It the summer a black or dark roof absorbs the suns rays and heats up, a lighter colored roof reflects much of the light. In the winter the darker roof is a much more efficient radiator of solar energy than a lighter one. A few days ago, Eli was up pretty high in a building that overlooked a bunch of row houses in a seedy to improving neighborhood, and he saw that most of the roofs were light, even on the houses that had not been tarted up. So he decided to use Google maps to take a look at the area he lives in. There are very few dark roofs left. Eli suspects that progress has falsified what the EPA says
Over 90% of the roofs in the United States are dark-colored.Take a look at your neighborhood. The web page continues about dark roofs
These low-reflectance surfaces reach temperatures of 150 to 190°F (66 to 88°C) and contribute to:
- Increased cooling energy use and higher utility bills;
- Higher peak electricity demand, raised electricity production costs, and a potentially overburdened power grid;
- Reduced indoor comfort;
- Increased air pollution due to the intensification of the "heat island effect"; and
- Accelerated deterioration of roofing materials, increased roof maintenance costs, and high levels of roofing waste sent to landfills.
In contrast, cool roof systems with high reflectance and emittance stay up to 70°F (39°C) cooler than traditional materials during peak summer weather. Benefits of cool roofs include reduced building heat-gain and saving on summertime air conditioning expenditures. By minimizing energy use, cool roofs do more than save money – they reduce the demand for electric power and resulting air pollution and greenhouse gas emissions.