Tree planting for energy conservation
Have you heard that by strategically planting trees and shrubs around your house you can conserve energy and thereby cut your home heating and cooling bills? In Minnesota, we spend about ten times more for heating than cooling costs, but energy savings in all seasons should be considered, and will add up over time! Can you remember the rules about where and what to plant? Here is a quick primer to get you started on life-long energy savings through purposeful planting!
- Q: I’d like to reduce my heating bill next winter. Where should I plant trees to shelter my house from cold, winter winds?
A: Your goal is to plant trees to cut cold winter winds before they enter your house. We also want to be sure not to plant on a side of the house that will block winter sunlight, which can actually help heat a house. To achieve both outcomes, your first priority should be to plant trees or tall shrubs within 20–50 feet from west-facing windows. You should choose an evergreen species because it will block winter winds from entering through windows, and give you the best summer shade. Alternatively, if you have the space in your yard, you could also plant a windbreak. This is a row of evergreen trees spaced 10–20 feet apart, planted in rows perpendicular to the to the primary winter wind direction, usually running along the west and north sides of the property.
Illustration adapted from material provided by U of MN SULIS- Q: My house gets really hot in the summer and I’d like to turn off the air conditioning from time to time. What is the best strategy for planting trees if I want to keep my house cooler?
- A: To keep your house cool naturally, you should plant trees on the west and east sides of your house. Your goal is to reduce the summer solar heat that enters your house through windows. By this time, you’ve already decided to plant evergreens on the north and west side of your home because it will keep you warm in the winter. Those trees will also shade your windows from solar heat in the summer. When planting near the windows on the east side of the house, you should select deciduous shade trees (trees that lose their leaves in the fall) because you’ll reap the summer shade but also get some solar heat gain in the winter. You can also plant a tree or shrub near your air conditioning unit to block the sun, increasing its efficiency by up to ten percent.
- Q: Is there any place I shouldn’t plant a tree for energy savings?
- A: Yes! You should avoid planting trees in front of windows on the south side of your home, since they can block the solar heat that can be gained in the winter. Trees planted in this area do not give the benefits of shade due to the angle of the sun during the summer in Minnesota. If you absolutely must put a tree near your south windows, chose a tree with small leaves, and “dappled” shade which will let in light such as Honey locust or Kentucky coffee tree.
- Q: Are there any other general tips to keep in mind when planting for energy savings?
- A: So glad you asked! Yes, there are a few other tips to keep in mind:
- Plant a tree whose mature height will not interfere with an overhead power line or the structure of your home.
- Plant the tree no closer than ten feet to your home but within 50 feet.
- Choose a tree/shrub that will fit well in your unique space, light, and soil conditions making sure it is a species resistant to damage from diseases and insects.
- Make sure to plant a tree species with strong wood since it will be close to the structure of your home, and monitor it in order to maintain its structure and safety. Ask a professional arborist or nursery person if you need help with tree care or selection.
- Q: Where can I go to read more about planting for energy conservation?
- A: Here are some good places to start: the Minnesota DNR and the University of MN Sustainable Urban Landscape Information Series.
