June 26, 2002—New research compiled by Plants at Work indicates that interior plants can play a critical role in offsetting escalating summer energy costs.
Plants cool by a process called transpiration, which, according to the US Department of Agriculture, decreases air temperature in offices by 10 degrees. A study out of Washington State University demonstrates that plant transpiration in an office environment releases moisture, creating a humidity level exactly matching the recommended human comfort range of 30 – 60 percent. The same study concludes that in the absence of plants, the relative humidity in offices runs below this recommended range. When the relative humidity is too high, the condensation of windows and exterior walls can result in costly structural damage.
According to the International Society of Arboricultural, the net cooling effect of one young, healthy interior tree is equivalent to ten room-size air conditioners operating twenty hours a day. According to literature from the Associated Landscape Contractors of America of Herndon, Va., proper selection and placement of plant materials can lower heating and cooling costs by as much as 20 percent.
For more information, contact Plants at Work.
