Landscaping For Energy Efficiency

Landscaping For Energy Efficiency

Are you looking for cost-effective yet eye-pleasing ways to lower your energy bills? Planting trees, shrubs, vines, grasses, and hedges could be the answer. In fact, landscaping is your best long-term investment for reducing heating and cooling costs, while also bringing other improvements to your community. (Not to mention the curb appeal and beauty it adds)
A well-designed landscape will:
* Cut your summer and winter energy costs dramatically.* Protect your home from winter wind and summer sun.* Reduce consumption of water, pesticides, and fuel for landscaping and lawn maintenance.* Help control noise and air pollution.
Landscaping Saves Money Year-Round
Carefully positioned trees can save up to 25% of a household’s energy consumption for heating and cooling. Computer models devised by the U.S. Department of Energy predict that the proper placement of only three trees will save an average household between $300 and $600 and more in energy costs annually.
During Hot weather
You may have noticed the coolness of parks and wooded areas compared to the temperature of nearby city streets. Shading and evapo-transpiration (the process by which a plant actively moves and releases water vapor) from trees can reduce surrounding air temperatures as much as 9 degrees F (5 degrees C).
Because cool air settles near the ground, air temperatures directly under trees can be as much as 25 degrees F (14 degrees C) cooler than air temperatures above nearby blacktop. Studies by the Lawrence Berkeley Laboratory found summer daytime air temperatures to be 3 degrees F to 6 degrees F (2 degrees C to 3 degrees C) cooler in tree- shaded neighborhoods than in treeless areas.
A well-planned landscape can reduce an un-shaded home's summer air-conditioning costs by 15% to 50%. One Pennsylvania study reported air-conditioning savings of as much as 75% for small mobile homes.
During cold weather and wind
You may be familiar with wind chill. If the outside temperature is 10 degrees F (-12 degrees C) and the wind speed is 20 miles per hour (32 kilometers per hour), the wind chill is -24 degrees F (-31 degrees C). Trees, fences, or geographical features can be used as windbreaks to shield your house from the wind.
A study in South Dakota windbreaks to the north, west, and east of houses cut fuel consumption by an average of 40%. Houses with windbreaks placed only on the windward side (the side from which the wind is coming) averaged 25% less fuel consumption than similar but unprotected homes. If you live in a windy climate, your well-planned landscape can reduce your winter heating bills by approximately one-third.
Compiled by Yehuda Draiman
PS
Greening your rooftops
The benefits of grassy rooftops are manifold - they reduce heat, clean the air, improve biodiversity and are relatively affordable
Rooftops are arguably the area with the greatest potential of all urban spaces for creating a higher environmental quality of life. A green roof or living roof is a roof covered with a dense mat of growing plants. Most people are familiar with the turf roofs used for centuries in Iceland; green roofs (developed in Germany in the 60s and 70s), essentially adopt the idea of turf roofs but instead of using mostly grasses, they employ drought- resistant plants appropriate to the tough conditions on a roof top. At its most basic, a waterproof membrane is installed on the roof, which is then covered with 8-15cm of soil and planted with low-growing succulents and alpine plants.
Techniques have become more sophisticated over the years and nowadays water-holding natural fibro panels are available, which give seeds or young plants good anchorage and ensure efficient water supply. The effect of green roofs can be astonishingly beautiful, especially when the plants start to flower. Succulents such as stonecrops and houseleeks are often the plants of choice because they can tolerate hot, dry conditions.
The benefits of a green roof are significant for both the environment and the purse.
Green roofs can greatly reduce the' heat island' effect by cooling and humidifying the surroundings through evaporation of moisture. A heat-trapping building removes a natural space from the environment but a green roof can compensate for concreted (sealed) land and improve biodiversity in the city.
Green roofs 'scrub' the air clean. The texture of the plants captures dust and particles of pollution in the air. In this way they get filtered out and bound within the soil, where they are broken down and even reabsorbed as fertilizer (this must be the ultimate in recycling).
Roof vegetation absorbs rainfall and helps reduce need for costly drainage systems at ground level. In high density areas like Athens where there is little green space for storm water to percolate into the soil, storage tanks and other forms of storm water management are structurally and economically not very viable. Green roofs have a high applicability to such urban zones where ground green space is in short supply.
Green roofs provide structural protection often extending the life of a normal roof two or more times over. Protecting structures from hail damage, UV rays and temperature fluctuations, a green roof also offers fire protection.
Green roofs insulate, cooling buildings in summer and reducing heat loss in winter. Researchers believe the attendant cost savings are very promising.
Vegetation absorbs sound, so noise pollution is reduced.