# Cool Roof Calculator

Estimates Cooling and Heating Savings for Flat Roofs with Non-Black Surfaces

• Developed by the U.S. Department of Energy's Oak Ridge National Laboratory (Version 1.2)
• This version of the calculator is for small and medium-sized facilities that purchase electricity without a demand charge based on peak monthly load. If you have a large facility that purchases electricity with a demand charge, run the Peak version of the calculator in order to include the savings in peak demand charges from using solar radiation control.
• What you get out of this calculator is only as good as what you put in. If you click here , you'll find help in figuring out the best input values. Some things, such as the weathering of the solar radiation control properties and the effects of a plenum, are especially important. You'll also find help in figuring out your heating and cooling system efficiencies and proper fuel prices.
• To compare two non-black roofs, print out results of separate estimates for each vs. a black roof. Manually compute the difference in savings to compare the two non-black roofs.
• If your energy costs are determined by on-peak and off-peak rates, print out results of separate estimates with on-peak and off-peak rates for the same roof. Judge what fraction of the savings with on-peak rates is appropriate.
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Oak Ridge National Laboratory is managed by UT-Battelle for the Department of Energy