"Cool Trees" Project
Project At a Glance
- Project: Plant 900 to 1,000 shade trees around county school and government buildings.
- Objective: Lower the amount of energy used to heat and cool county facilities.
- Process: Place native canopy trees on east, west, and south facing façades, with adequate space between trees with attention to the landscape's function and aesthetic.
- Benefits: Conserve 4.5 million kilowatt hours of energy for cooling, intercept 150 million gallons of stormwater; save $1.8 million.
- Funding: $500,000 from Department of Energy, Energy Efficiency Conservation Block Grant Program.
In December 2009, Baltimore County was awarded $7,403,600 from the Energy Efficiency Conservation Block Grant Program (EECBG), a program funded by the American Reinvestment and Recovery Act.
The Cool Trees Project has been completed, using $500,000 allocated to tree planting from the EECBG program. The Department of Environmental Protection and Sustainability (EPS) worked with the Property Management Division of the Office of Budget and Finance, the Department of Recreation and Parks, the Baltimore County Public Schools Office of Maintenance and Grounds, and the county landscape contractor. The Cool Trees Project planted 957 native shade trees at 46 county schools, eight police precincts and PAL centers, seven community centers, five senior centers, all three Community College of Baltimore County (CCBC) campuses, two libraries, two fire stations, and one health center.
Tree Selection and Placement
Not all trees are created equal. EPS focused on choosing trees that not only provide shade, but that reflect the native Maryland canopy, match the particular site conditions, and compliment the existing landscape. Such beneficial and versatile trees include:
- Northern Red oak (Quercus rubra)
- Pin oak (Quercus palustris)
- Scarlet oak (Quercus coccinea)
- ‘Valley Forge’ American elm (Ulmus americana)
- ‘October Glory’ Red maple (Acer rubrum)
- Littleleaf linden (Tilia cordata)
Landscaping for energy efficiency involves both tree species selection and placement. In temperate regions of the northern hemisphere, trees are placed on the east, west, and south facing façades, enabling the most shade to be cast on the buildings during the warmest months of the year.
In addition to significant energy benefits, trees planted as part of the Cool Trees Project will intercept stormwater, remove atmospheric carbon, and increase the aesthetics of public facilities.
Calculations using the National Tree Benefit Calculator estimate the following savings from the 957 trees over the next 30 years:
- The trees will save 4,537,137 kilowatt hours (kWh) of energy, equating to $344,433 in savings.
- The trees will absorb 143,477,268 gallons of stormwater, equating to $1,420,408 in savings.
- The trees will provide $247,020 savings based on air quality improvement.
- The trees will help conserve 152,163 therms of natural gas, equating to $160,077 in savings.
- The trees will help sequester 15,622,068 pounds of carbon dioxide (CO2).
Revised July 23, 2015
Revised April 6, 2016