This is part of a continuing series of articles on simple, inexpensive energy saving tips to implement now that will produce real, measureable, quick energy savings, monetary gains, and greenhouse gas (GHG) emission reductions. These are suggestions that will not “put out” your staff, but make you look like a hero.
Turn your roof into a “Cool Roof”
Cool roofs are roofs that reflect and absorb less of many kinds of solar radiation, such as visible, infrared, and ultraviolet wavelengths. Common roofs have a high thermal emittance, allowing the heat energy from this radiation to enter the building, causing an additional heating load for your air conditioning system. Besides the cost saving benefits of taxing your air conditioning system less, cool roofs also save money by extending the life of your roof. Summer temperatures on black roofs can reach 150°F. Cool roofs reduce this peak temperature by as much as 50°F, reducing the “heat island” effect on the roof which can cause premature damage to your roof and structures on it.
A University of Central Florida study showed a strip mall’s cool roof caused average electricity savings of about 25% (http://www.fsec.ucf.edu/en/publications/pdf/FSEC-CR-964-97.pdf). In addition to this usage decrease, a significant decrease in peak demand during the summer months was measured, as well. More buildings are now required by their utility to pay extra charges for high instantaneous demand during the summer.
These benefits can be easily achieved by merely painting your black roof. It does not have to be white; silver or light blue are popular colors that have a positive effect. More manufacturers are producing light-color roofing materials these days.
Of course, by not allowing heat to enter a building cool roofs may cause your boiler to combust more fuel in the winter to heat occupants for comfort. Thus, overall cool roof cost savings will vary based on local climate. Several studies indicate that unless the building is located in an area of long, severe winters, most buildings will receive some overall economic benefit from installing a cool roof. According to the UCF study, the ROI was about 9 years. So, while you may not want to convert an otherwise good roof to a cool one now, if a roof needs replacement anyway, request cool roof materials.
Remember, installing a new cool roof is not the end. Like many other new technologies, proper maintenance is important or else energy savings of cool roofs will drop over time.
CCES has experience in performing site-specific energy audits and recommend proven strategies and technologies used by others to reduce your facility’s energy usage, saving you money with a good ROI and without inconveniencing your staff.