The use of solar energy in homes

The post-industrial revolution world that we live in is a product of fossil fuels such as petroleum. All that we take for granted has been built on this non-renewable commodity and all indications are that in the next few decades, reserves will come to an end.

Our homes are vast consumers of oil in the form of electricity. While lighting and appliances like television sets consume their fair share of electricity it is the process of cooling or heating a property that takes the largest bite of energy consumption.

Unfortunately, Malta, although a country blessed with almost unlimited amounts of sunlight, has been lagging behind in solar energy utilisation. The present government seems to work using crisis management instead of looking ahead.

It is only now that petroleum prices have skyrocketed that the government is making half-hearted noises about alternative sources of energy for households. In the Budget speech the Minister of Finance emphasised the role of education; however it is legislation and economic incentives that are ultimately the driving force behind the right choices.

There are well established regulations regarding health when it comes to building houses but few, if any, laws apply to energy saving practices. For example the use of solar water heaters should be encouraged by giving their utilisation legislative backing.

This can be done by making it compulsory to install these heaters in all new houses. Economies of scale and government tax incentives will help to bring their prices down considerably.

Although Malta is perceived as being a 'warm' country, for at least a third of each year the temperature drops sufficiently to make it necessary to use some form of heating inside homes which unfortunately usually depends on oil (indirectly in the form of electricity) or other fossil fuels. However our climate is ideal for employing so-called passive solar heating.

The principles of passive solar heating are well established, their lack of utilisation is again due to a lack of legislative backing. Some of the standard practices used in passive solar heating such as a well insulated building envelope are also efficient at keeping a house cool during the summer.

Nevertheless there are ways of actually cooling a home by using solar energy. Many passive solar designs include natural ventilation for cooling. Windows used in the winter for solar heating can be fitted with vertical panels called wing walls on the windward side of the house.

These panels accelerate the natural breeze in the interior to keep it cooler. Another passive solar cooling device is the thermal chimney which vents hot air from the house through the roof, while drawing in cool air from pipes buried beneath the ground. Retrofitting an already built home with solar-assisted heating and cooling is also possible but an architect conversant with the principles and techniques involved must be consulted.

The Malta Labour Party, in its document on Environmental Policies for Malta, stresses the importance of government commitment in the use of renewable and perpetual energy sources. The same document emphasises the need for government incentives for the use of solar energy for domestic use.

It is also mentioned that Government should incentivise not just the home owner but also private enterprise to encourage investment in research and development of alternative sources of energy.