October 15, 2009
Concern about carbon emissions and associated climate change, along with rising fuel costs, have made energy conservation a pressing public policy issue. Increased planting of urban shade trees has been suggested as one way of conserving energy by reducing the demand for heating and cooling. Indeed, some utility companies offer customers free or reduced-cost trees. However, no studies of utility billing data had shown that trees reduce energy consumption.
The Value of Shade: Energy and Climate Impacts Resource List
Misha Sarkovich, Residential Services, Sacramento Municipal Utility District (Sacramento, CA)
Trees planted in the right spaces in our urban environment provide shade and offer significant energy savings. Each year, the Sacramento Municipal Utility District (SMUD) invest over $1.4 million into the Sacramento Shade program, with which the Sacramento Tree Foundation hires staff, purchases trees, and provides other support to plant more than 13,000 new shade trees. Participants receive tree selection, planting and care guidance along with healthy trees for shading their homes, schools, parks and streets. This model program is the largest and most successful of its kind. Since the program inception in 1990, SMUD had planted more than 450,000 shade trees at approximately 150,000 residential homes. In addition, SMUD gives out 4,000 trees for schools, parks and streets to mitigate the urban heat island effects and engages thousands of volunteers in the planting and care of community trees.
Geoffrey Donovan, Research Forester, Portland Forestry Sciences Lab (Portland, OR)
Previous studies reviewing the effect of shade trees on energy use fell into two categories: (1) small-scale controlled experiments that examined the effect of trees on an individual house and (2) large-scale simulation modeling. Generally, results showed that the trees reduced seasonal cooling costs by between 26% and 47%. However, none of these studies used actual electricity billing data. New research now closes the literature gap that links energy savings and urban trees.
Jacobe Caditz, Sacramento Shade Director, Sacramento Tree Foundation (Sacramento, CA)
Partnering with the local electric utility, Sacramento Municipal Utility District (SMUD), the Shade Tree Program provides education and quality trees to residents with the goal of shading buildings and reducing energy consumption. Sacramento County residents are eligible for up to 10 free trees through the Sacramento Shade Tree Program. Since 1990 almost 400,000 trees have been planted through the program- making this a nationwide model for utility nonprofit partnership. The Sacramento Shade tree program offers more than 25 trees of varying sizes. All of the available trees are deciduous, so they shed their leaves in the fall to allow the warm winter sun into your home. Residential customers who want a tree need only schedule an appointment with a Sacramento Tree Foundation Community Forester to discuss the best location for the trees. The Foundation will deliver the tree with all the necessary supplies including trees, stakes, ties, and fertilizer. In addition, SMUD funds another urban heat-island mitigation effort, Community Shade. SMUD offers free 15-gallon container trees for planting in public areas such as parks, playgrounds, and schools. These trees provide additional indirect cooling of the urban heat island via evapotranspiration, as well as help beautify public places.
Webcast attendees will learn:
* The effect of trees on carbon emissions due to decreased electricity use and from direct sequestration.
* How the magnitude of energy savings depends on the tree’s location.
* How shade tree programs benefit utilities (looking at when the wholesale price of electricity varies by time of day but the retail price does not)
* Working with developers for energy considerations.
* Making the case to homeowners who experience virtually none of the carbon and stormwater benefits of tree planting, and whether a subsidy to encourage tree planting is warranted.
About the Third Thursday Webcast Series
The Third Thursday Webcast Series is the Alliance for Community Trees’ monthly webcast series held at the lunch hour and made possible through support from The Home Depot Foundation and USDA Forest Service. The goal is to create informal training opportunities for local urban and community forestry organizations. The content is geared to mainly serve the needs of volunteer organizations and community groups, although webcasts are open to all.
The trainings leverage local successes by amplifying to a larger audience the model organizations’ methods, materials, and approaches. Sessions are planned to last no more than one hour, with two presenters speaking on the same topic from slightly different perspectives, each for 10-15 minutes, followed by 10-15 minutes of questions and answers.
CEU Approved: 1 Hour
CFE Category 1 Approved: 1 Hour