Passive solar energy and passive solar design refer to the planned harnessing of the sun’s energy for the purpose of both cooling and heating of living spaces. Using passive solar energy buildings are designed in such a way as to take the maximum advantage of the natural energy capture abilities of certain materials when they are exposed to sunlight. If designed well, passive energy systems are invariably simple, easy to use and require little maintenance due to their lack of mechanical or moving parts.
Common features of passive solar design are thermal mass, thermal chimneys and operable windows (ie windows that can be opened). Thermal mass is any building material that is efficient in storing heat for a long period of time (such as masonry or water). The use of thermal mass is crucial because it helps to prevent any fast fluctuations in temperature. Thermal chimneys reinforce and / or create the movement of hot air rising upwards in order to control the movement of air for the purpose of cooling.
One common example of design used to trap heat is the addition of glassed areas onto houses. This is an addition that, comparatively speaking costs very little, particularly when building from scratch, but is highly effective at capturing and storing heat, especially when used in conjunction with double or triple glazing, adjustable blinds and efficient wall insulation.
In the UK, we currently only benefit from about 14% of space heating through passive energy and therefore have a long way to go when it comes to taking advantage of this particular energy source. A tightening of building standards and a sea change in the way we build and use our homes is needed in order to make the most of this energy. On the other hand that means there are all kinds of cheap and easy measures people can take to improve the energy retention of their homes and bring down the cost of their heating and electricity.
Passive solar energy is something all new buildings should take into account as it is integral to the design of any building and if done correctly, will add no extra cost to construction, but will save money and resources for the lifetime of that new building. Glass, insulation, location and orientation of the building and even the position of rooms and services can all play a factor in making any building as efficient as possible and capable of making use of passive solar energy.