windbreak

In this paper the authors describe in detail the planted circumstances with wind-break effects developed in the isles of Tonaki and Aguni. tens of kilometers off the main island of Okinawa in the East China Sea; both these isles are abundunt in Fukugi, an evergreen, tall and sturdy tree of tropic origin; and the time-honored Fukugi groves have played an all-important role in protecting the people and their properties against the year-round strong winds and casual but frequent typhoons.

Effects of a coniferous windbreak on electrical energy use in a 66-unit mobile home park in central Pennsylvania were studied during the winters of 1981-82 and 1982-83.

The heat losses from small houses, due to transmission and ventilation, are estimated. The estimation i s based up on the house owness daily readings of electricity and water meters, and their notes on behaviour influencing the energy use. Consideration is taken to heat supply from insolation and from people. Hot water losses are calculated from use of water and use of household machinery. Besides the estimation of the heat losses, Q, wind and temperature in the area is registrated .

Windbreaks probably are more important for reducing infiltration of cold outside air into houses than for reducing convective heat losses. It is difficult to estimate the magnitude of tree effects on energy use for space conditioning on a year-round basis, but past studies suggest that trees have the potential to reduce winter fuel consumption by 10-25%. Describes several studies of trees as windbreaks and for summer shade. Discusses location of trees with respect to buildings.

Evaluates the space-conditioning energy conservation potentials of landscapes designed to ameliorate building microclimates. The physical bases for vegetative modifications of climate are discussed, and results of past study of the effects of vegetation on space-conditioning energy consumption in buildings are reviewed. The state-of-the-art of energy-conserving landscape designs is assessed and recommendations are presented for further research. Landscaping mobile houses and single family dwellings is considered.

During winter experiments in central Pennsylvania a windbreak, 61 metres long and composed of a single row of white pine trees, significantly reduced air infiltration rates and space heating energy needs in a small mobile home by upto 54% and 18% respectively. Greatest reductions in air infiltration rates occurred with the home at one windbreak height (1H) downwind, even though maximum reductions in wind velocity occurred at 2H or 4H downwind. Space heating energy savings were less sensitive to downwind position, with maximum energy savings measured at both 1H and 2H.