Landscaping to Help Landscaping to Help Conserve EnergyConserve Energy

Master Gardener Volunteers TrainingMaster Gardener Volunteers Training

Why landscape with energy Why landscape with energy efficiency in mind?efficiency in mind?

Cut summer and winter energy costsCut summer and winter energy costs Protect your home from windsProtect your home from winds Help control noise and air pollutionHelp control noise and air pollution Increase the value of your homeIncrease the value of your home

An average landscaped house is worth An average landscaped house is worth 10-15% more than a bare landscape.10-15% more than a bare landscape.

A value that could be greater than $10,000!A value that could be greater than $10,000!

The United State Department of The United State Department of Energy states the proper placement Energy states the proper placement of only three trees could save about of only three trees could save about $100-$250 in ANNUAL energy costs.$100-$250 in ANNUAL energy costs.

The return to investment - The return to investment - 8+ years.8+ years.

Considerations for Maine:Considerations for Maine:

Maximum sun warming effects in the Maximum sun warming effects in the winterwinter

Maximum shade during the summerMaximum shade during the summer Deflect winter winds away from Deflect winter winds away from

buildingsbuildings Funnel summer breezes toward the Funnel summer breezes toward the

home.home.

Three methods of heat exchangeThree methods of heat exchange

1.1. Air InfiltrationAir Infiltration

2.2. ConductionConduction

3.3. RadiationRadiation

1.1. Air InfiltrationAir Infiltration– Passage of outside air through cracks Passage of outside air through cracks

and openings.and openings.– Strong winds against a building Strong winds against a building

increase air infiltrationincrease air infiltration– As air enters through openings, an As air enters through openings, an

equal amount of air (usually warmer) is equal amount of air (usually warmer) is forced out of the home through forced out of the home through openings that face away from the windopenings that face away from the wind

– Can represent Can represent 50%50% of heat loss on of heat loss on cold, windy daycold, windy day

2.2. ConductionConduction

Heat loss through materials. Dependent Heat loss through materials. Dependent upon temperature difference between upon temperature difference between inner and outer surfaces.inner and outer surfaces.

3. 3. Solar radiationSolar radiation – – warmth directly warmth directly from the sun from the sun

East or west facing windows East or west facing windows allow for allow for hot summer sunhot summer sun

South facing windows allow South facing windows allow heat for heat for winterwinter

Summer ConsiderationsSummer Considerations

northwinter

summer

ShadeShade

Shading is the most cost-effective Shading is the most cost-effective way to reduce solar heat gain and way to reduce solar heat gain and cut AC costscut AC costs

Shade and evapotranspiration Shade and evapotranspiration from trees can reduce from trees can reduce surrounding air temperature as surrounding air temperature as much as 9much as 9oo

Shading an AC unit can increase Shading an AC unit can increase efficiency by 10%efficiency by 10%

In summer, trees and shrubs can reduce In summer, trees and shrubs can reduce the amount of solar radiation hitting the amount of solar radiation hitting outside surfaces, thus reducing heat outside surfaces, thus reducing heat conduction into homes.conduction into homes.

Because cool air settles, air Because cool air settles, air directly under shade trees can be directly under shade trees can be 2525oo cooler than nearby blacktop. cooler than nearby blacktop.

Shade considerations:Shade considerations:

Deciduous trees are best;Deciduous trees are best;they maximize summer shade they maximize summer shade and winter sunand winter sun

Plant on the south and Plant on the south and southwest sides of buildingsouthwest sides of building

Trees with high, spreading branchesTrees with high, spreading branchesprovide maximum roof shadingprovide maximum roof shading

Place large trees no closer than 20 feet Place large trees no closer than 20 feet from the house.from the house.

Good shading requires the knowledge Good shading requires the knowledge of the size, shape and location of the of the size, shape and location of the moving shadow.moving shadow.

Trellises and arborsTrellises and arbors

Cool the house by reducing solar radiation Cool the house by reducing solar radiation hitting the househitting the house

Deciduous plants cool in summer, allow sun Deciduous plants cool in summer, allow sun in in winterwinter

Don’t attach plant Don’t attach plant

directly to buildingdirectly to building..

Use plants to shade ground and Use plants to shade ground and pavement around the home.pavement around the home.

– It reduces heat radiation and coolsIt reduces heat radiation and cools

the air before it reaches walls the air before it reaches walls

and windows.and windows.

Shading the roof of a house by large Shading the roof of a house by large trees can reduce inside temperature by trees can reduce inside temperature by 8-108-10oo

Winter ConsiderationsWinter Considerations

north

summer

winter

In the winter, deciduous trees and In the winter, deciduous trees and shrubs can reduce the rate of heat shrubs can reduce the rate of heat loss by allowing the winter sun to loss by allowing the winter sun to raise the outside temperature of raise the outside temperature of walls.walls.

Wind EffectsWind Effects

Unprotected homes lose much more heat on Unprotected homes lose much more heat on cold windy days than on equally cold still days.cold windy days than on equally cold still days.

Up to 1/3 of heat loss may occur through heat Up to 1/3 of heat loss may occur through heat loss from the walls and roof via conduction.loss from the walls and roof via conduction.– Wind increases the convective air currents Wind increases the convective air currents

along walls and roof, thus increasing heat along walls and roof, thus increasing heat lossloss

Infiltration or air leakage can account for as Infiltration or air leakage can account for as much as 1/3 of heat lost from some buildings.much as 1/3 of heat lost from some buildings.

WindbreaksWindbreaks

Can reduce winter fuel consumption by 10-Can reduce winter fuel consumption by 10-30%.30%.

Best planted on the north and northwest Best planted on the north and northwest sides of the home.sides of the home.

They are most effective when plants They are most effective when plants branch to ground level. Evergreens best branch to ground level. Evergreens best for this.for this.

The wider the planting, the more effective.The wider the planting, the more effective. When planting more than one row, stagger When planting more than one row, stagger

the plantings.the plantings.

Windbreaks cont.Windbreaks cont.

Locate the wind break 2-5 times the Locate the wind break 2-5 times the mature height of the trees from the mature height of the trees from the househouse

20 ft

40 – 100 ft

Remember snow typically drifts in an area from 1-3 times the height of the trees, so plant appropriately!

Dead Air SpaceDead Air Space

Foundation plantings planted close to Foundation plantings planted close to buildings reduce wind currents that buildings reduce wind currents that otherwise would chill outside surfaces otherwise would chill outside surfaces (conduction heat loss).(conduction heat loss).

Foundation plantings create a “dead air” Foundation plantings create a “dead air” space which slows heat loss from the space which slows heat loss from the building. Also will help insulate the house building. Also will help insulate the house from hot outside air in summer.from hot outside air in summer.

By reducing air velocity, air infiltration heat By reducing air velocity, air infiltration heat losses are also reduced.losses are also reduced.

Evergreens are most effective for both winter warming and summer cooling.

Place plants from 1-5 feet from the building.

Resources:Resources:

Landscape Plantings for Energy SavingsLandscape Plantings for Energy Savings

http://extension.missouri.eduhttp://extension.missouri.edu Landscaping for Energy ConservationLandscaping for Energy Conservation

http://osufacts.okstate.eduhttp://osufacts.okstate.edu Landscaping for Energy EfficiencyLandscaping for Energy Efficiency

http://apps1.eere.energy.gov/consumer/http://apps1.eere.energy.gov/consumer/your_homeyour_home