Energy Sources and Environmental Considerations

Energy sources

Energy for warmth and light is obtained from coal, oil, gas, wood, peat, wind, water, sun and nuclear power.

Many of these sources are used to produce electricity which in turn is used in the manufacture of all our physical needs, such as clothes, medicines, heat and light. Some fuel sources are used for transport. There are costs involved in producing energy sources, financial costs and also a cost to the environment. Environmental considerations should always be considered against the financial and comfort costs.

Coal, oil, natural gas and peat have taken many thousand of years to form in the earth. They are being used up very rapidly at present and cannot be replaced. They are non-renewable and are referred to as fossil fuels. Wood is renewable but takes many years to replace. Nuclear power can be used for many years using fissile plutonium but if nuclear fusion can be developed this source could be everlasting.

The sun, wind and water can also be used as sources of energy and these can be used indefinitely. They, along with nuclear fusion, are said to be renewable sources of energy. At the moment fossil fuels are the most used sources of energy and they are exploited mainly by the western world.

Environmental considerations:
Environmental damage is inevitable from all fuels and has to be accepted to some degree if we are to maintain energy use at present levels. The economic cost of having to meet environmental needs is being met by the introduction of techniques such as flue gas desulphurisation in the case of coal, in an attempt to reduce the amount of gases emitted to the air. Unleaded petrol is now widely used in cars. Ways of reducing carbon dioxide in the environment are being actively investigated.

There are two main types of effect on the environment from energy processes: the physical and the chemical

Physical pollution:

The production and transportation of energy have effects on the physical environment. For instance:  a wind turbine, or the chimney of a power station, or the pylons and network to transport power around the country.  All of these have a visual effect on the landscape.

On the other hand – reliable power is essential to our lives – in our homes, on our farms, in our schools and factories, and in hospitals and offices.  When developments are taking place, it is important that environmental effects are taken into account and the cost of these effects, as well as remediation actions, are weighed against the benefits of sustainable power.   In order for Ireland to have cleaner power from renewable energy, we need to transport it to people who will use it, or even to export it abroad.

Chemical pollution:
The chemical sources of pollution can be injurious to health either directly or indirectly through the food chain. The resulting damage may be physical in nature, for example, acid rain will cause serious damage to buildings over time, to forestry and also to fish in rivers.  

Environmental considerations

	The effects of pollution on the environment include: Acid rain as mentioned above. Global warming which is as a result of the greenhouse effect, and is also due to fossil fuel use.
	Global warming is being blamed for many of the present climatic excesses, such as flooding, rising temperatures and droughts

Accidental or deliberate leakage of oil can cause serious environmental problems. The oil slick and the burning of oil wells in the Persian Gulf in 1991 are regarded as the worst environmental disaster in history.

Nuclear accidents can and do happen as was proved by Chernobyl.
 

Fuels of all kinds carry with their use environmental consequences. The burning of fuels in buildings or for transport releases some quantity of toxic emissions in the form of smoke, hydrocarbons, sulphur dioxide, nitrogen oxides, lead, benzene and other compounds into the atmosphere.

Energy conservation and efficiency:
The finite nature of fossil fuels has led to campaigns to conserve energy but without loss of comfort. To achieve this, ways must be found of using our energy more efficiently.

Some examples include reducing wastage by improving the fabric of houses through insulation and other means. Insulating your home can reduce heating bills and increase comfort. Turning off appliances, heating and lights when not required are other means which are inexpensive and are worthwhile in economic terms.

To date alternative sources of energy have not been used to their full potential in Ireland. Hydro-electricity resources have been developed and what exists is relatively small but significant. Wind farms are becoming more prominent.

At a personal level energy can be conserved by wearing clothes which retain heat (insulation).

At the industrial and commercial level recovery of energy is becoming more common. Waste heat recovery is now widely used for example. The heat generated in one process is used for another.

Many homes and schools are poorly insulated and lose heat. This loss can be reduced by proper insulation and the inclusion of efficient control systems.

Transport systems can be improved either by sharing, using a better public transport system, or by people cycling and walking.

Energy conservation and efficiency

Energy conservation is not the same as energy efficiency.

Homes which have been made more energy efficient through improved insulation have not always led to energy conservation. It is important to determine how energy is used in the home in order to find ways of improving efficiency. 'Energy Audits' is one way of achieving this.

They are carried out in two stages:

1. Determine how much energy was used in the previous twelve months and how much it cost.
2. Set up a programme to show how energy can be conserved and to determine where, how and by how much energy savings can be made.

The efficient use of energy in one area when it is not overcompensated by waste in another will lead to conservation.

Activities:
Complete this crossword on Energy Sources.

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