Passive Solar building and low energy design
Architects make use of various techniques to increase the ability of buildings to generate or capture their own energy and to lessen the energy needs of buildings. The single most important goal of sustainable architecture is achieving energy efficiency over the entire life cycle of a building.
Well-insulated buildings are of primary importance and are a cost-effective element of an efficient heating, ventilating, and air conditioning (HVAC) system. A more efficient building requires less heat dissipating or power generating. However, to expel polluted indoor air it could require more ventilation capacity. Building and site orientation have extensive effects on a building’s HVAC efficiency.
HVAC systems powered by motors and the use of copper as opposed to other metal conductors, aids to improve the electrical energy efficiencies of motors, thus enhanced sustainability of electrical building components is achieved.
Significant amounts of energy are flushed out of buildings in the compost, air and water streams. Energy from waste hot water and stale air can be effectively recaptured and redirected by off the shelf, on-site energy recycling technologies into incoming fresh cold water or fresh air. Centralised anaerobic digesters are required to recapture energy for uses other than gardening from compost leaving buildings.
The energy of the sun can be harnessed efficiently through passive solar building design. This method excludes the use of active solar mechanisms such as solar hot water panels and photovoltaic cells.
Building materials that retain heat effectively with high thermal mass and the prevention of heat escape with strong insulation are very typical for a passive solar building design. To reduce the need for artificial cooling and relieve the level of solar heat gain during the summer months, low energy building designs require the use of solar shading, by means of shutters, awnings or blinds. Additionally a low surface area to volume ratio to minimize heat loss is typical of low energy buildings. Therefore, this is why more centralised structures are often constructed as opposed to the more ‘organic’ looking multi-winged building designs.