Increasing Energy Efficiency
with Vegetation

Use vegetation to increase energy efficiency

Houses use 22 percent of the energy consumed in the United States today. About half of this is for heating and cooling. A properly designed landscape can make a home significantly more energy efficient and reduce air pollution, including greenhouse gases. It can also cut heating and cooling bills by as much as 40 percent.

An energy-conserving landscape utilizes trees, shrubs, groundcovers and vines to provide cooling summer shade as well as insulation against heat loss in winter. It also serves aesthetic purposes. A windbreak, for example, can define the space in a yard or patio and provide privacy while blocking blustery winds. And by using plants as living air conditioners or insulating blankets, you can soften a building’s architectural edges with foliage and flowers while improving its performance.

Know your climate region

Energy saving strategies for buildings are in large part determined by geographic location. The U.S. Department of Energy has divided up the United States into four climate regions — cool, temperate, hot and arid, and hot and humid — and has recommended these landscaping strategies for each zone:

Cool

• Use windbreaks to protect buildings from cold winter winds.
• Avoid planting tall vegetation on the south side of the house that may prevent the sunlight from reaching walls or windows.
• Shade south and west windows and walls from the direct summer sun if summer overheating is a problem. Deciduous plants can be used to provide summer shade while allowing low-angle winter sunlight to warm your home during the coldest months.

Temperate

• Locate vegetation so that it does not block the winter sun.
• Locate vegetation so that it shades the roof, east and west-facing walls.
• Deflect winter winds away from the house.
• Funnel summer breezes toward the house.

Hot and arid

• Provide shade to cool roofs, walls, and windows.
• Landscape around your home so that it is cooled by evapotranspiration, the release of water vapor from the soil and plant surfaces into the atmosphere.
• Funnel summer breezes toward your home if it is cooled naturally and does not rely upon air conditioning.
• Deflect wind away from houses that are air-conditioned.

Hot and humid

• Make the most of summer shade with trees that allow low-angle winter sunlight to warm the home.
• Avoid locating planting beds close to the house if they require frequent watering.
• Direct summer breezes toward the house.