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Renewable Energy

In Britain, as elsewhere, this is a challenging time for the energy industry.

Environmental concerns, in particular, cast a shadow over the electricity production. But it is a time for opportunities, as well as stress, and tribute to the privatization of the electricity industry, renewable energy is set to boom. Indeed, it is estimated that up to the fifth of Britain’s electricity requirements could realistically be met from renewable sources by the year 2025.

The installation of a water turbine. Erection of a wind-farm. The construction of a waste-to-energy plant - all are the responses to the new opportunities for renewable energy in Britain today.

Currently, electricity generation in Britain is dominated by the use of fossil fuels: oil, gas - which has become increasingly popular in recent times – and particularly coal. About three quarters of British electricity is produces in coal-via-power stations.

The majority of the non-fossil-generated electricity supply to the grid comes from the nuclear power. With renewable energy at present accounting for only a smaller part of the country’s electrical power, around 2% of the total - most of it from hydropower. What is really giving a push to the development of renewable energy and has enabled many projects to go from drawing - board concepts to reality, was the privatization of the British electricity industry combined with the offering of commercial incentives.

The key factor in encouraging the development of renewable energy by large and small companies alike was a Major (in 1989) Electricity Act, known as the Non-Fossil Fuel Obligation. Under this scheme a guaranteed initial market is provided for approved renewable projects to help them get off the ground and become fully competitive. The privatized electricity industries together with the arrangements for subsidizing for the use of renewable energy are regulated by offer.

“The government wish is to encourage new renewable projects. It is recognized that at the present stage they could well be more expensive to run than traditional generation projects. So it’s needed to provide additional finance. It’s thought the best way of doing this was to put a levy on traditional fossil fuels - such as coal, oil and gas - so that a little extra revenue could be raised on them to finance the new renewable projects”

“Wind Cluster was delighted when the government announced a new subsidy scheme on Non-Fossil Fuel Obligation and without that assistance wind energy development could not take off. And we are very pleased this happened and we hope to see much more of it in the future”.

In planning future role in the electricity market-place for the renewables, environmental considerations play a significant part. As public concern grows over the damage being done to the environment by our industrial consumer society and in particular by the burning of fossil fuels in power generation, the renewables are coming increasingly to be seen as a desirable and environmentally-friendly option.

“Most methods of generating electricity involve some of defects, damages to the environment, and of course, in particular, we have in mind the emission pollution that comes from fossil fuels - gas, coal and oil. Those emissions take the form of sulphur doixide and magnesium dioxide, and acid rains cocktail, and also the carbon-dioxide which is a major contributor to potential global warming. So there is a great interest in renewable energies insofar as they avoid those environmental damages.”

Renewable energy, of course, is a traditional power source. It was only in the last century that it was largely squeezed out by the use of fossil fuels, and the wheels and sails stopped turning. Today, the growing awareness of the environmental damage, caused by fossil fuels caused the resurgence of renewable energy in new forms. It is increasingly seen as having a role to play in a move towards sustainable future. “…All forms of fossil fuel - coal, oil, gas and nuclear - all have one, and some of them many environmentally similar problems… Renewables are…more benign, if not completely benign…” Although the scope for developing more of these large-scale schemes in Britain is limited, because most of the suitable sites have already been exploited, there is, however, a potential for developing water-power on a smaller scale. Such as here, for example, across Scotland where local land-owners have joined together to install a small-scale hydro-scheme on a local river. The work involves diverting river water through a pipe down the cliff-face to drive the turbine below. When operational, this scheme will deliver enough electricity to the grid to meet the need of 500 homes. At the mouth of the Severn is Britain’s most significant site for another possible source of water power: electricity from the tides. By placing of a barrage across the estuary and building turbines into it, the rise and fall of the tides can be harnessed and used to generate electrical power. There is considerable potential for tidal energy along the western coasts of England and Wales, and the barrages were built across all the practical estuaries. This could meet a quarter of the country’s present electricity requirements. This will provide considerable environmental benefits by saving on the use of coal and therefore the emission of many millions of tons of carbon-dioxide and other pollutants into the atmosphere each year. There will also be a notable impact on the local ecologies.

So, studies are continuing to examine further the environmental effects together with the costs and technical performance.

A power of the sea is a tremendous force, and investigations are under way to study how to harness the energy of the wave. Optional is very large, the costs of converting it into the electricity extremely uncertain. Wind-power is becoming an established option in the British energy equation moving on from the research and development stage to the application on the local scale, the harvesting of the wind for electricity generation is now entering the mainstream. Wind Farms are springing up around the country to capitalize on the opportunities, renewables have to offer.

Britain has the best wind resources in Europe, so there is plenty of opportunity for setting the generators and indeed avoiding areas of real environmental sensitivity.

The locating of Wind Farms does, of course, raise environmental issues and debates on the scale of implementation. “Our philosophy is based on that of Denmark, where wind technology first took off in Europe”.

Radiation from the sun is high in energy even in northern latitudes such as Britain. With careful building design the sun’s heating and lighting properties can be enhanced, so reducing the need for artificial heat and light.

But also it is possible to convert the sun’s rays directly into electricity, using what are known as photo-voltaic sells. The researchers are examining whether this technology could compete effectively with other forms of electricity generation.

Investigations are also being conducted into geo-thermal power, the drawing of heat from the hot rocks below the earth’s surface to generate electricity. Geo-thermal energy is a major resource but it presents a formidable technological challenge, and the search continues in collaboration with other countries to turn it into an economically viable proposition.

Of considerably more interest at present, however, is the generation of electricity from a whole range of bio-fuels and wastes. Bacteria act on the sewage in enclosed tanks, creating methane, which is a bio-gas. This gas is fed into the power house where it is used to produce electricity for the national grid.

Methane is a powerful green-house gas and its consumption here for the production of electricity creates notable environmental advantages.

“Electricity generation from sewage-gas is environmentally friendly for 2 reasons: firstly, by producing the electricity from this renewable source, we are not burning fossil fuels; secondly by using methane in a power-generation scheme, this gas will not be escaping into the atmosphere and thereby will not contribute to the global warming effect.”

In Britain about 50 million tons of household and commercial wastes are produced each year. And 90% of these are placed in land-fill sites. Here again, the action of bacteria creates a methane-based bio-gas, which can be extracted and used for the generating of electricity, at the same time preventing it from causing harm by escaping into the atmosphere.

A variety of interesting specialized schemes have been developed for reclaiming energy from waste. Tyres-to-electricity, for example. As the number of vehicles on the roads increases, so does the problem of disposing of millions of scrap-tyres.

The tyres, in fact, have a higher calorific value than coal and work up a significant energy potential. In Ire, in rural Suffolk, is another rather unexpected response to the new opportunities in the energy market place. Opened in 1992, this is the world’s first electricity generating station fuelled by chicken litter or manure. It generates enough electricity for 12500 homes. You can see the waste products of millions of hens in surrounding poultry farms. The disposal of these wastes would normally present an environmental problem, and they would be spread on the land resulting in releases of methane into the atmosphere and microbes into the water supply. Now, with their use in the power station, this pollution problem is removed, as well as electricity generated.

And in forestry the residue of the tree-tops and branches that are usually left on the forest floor when the trees are harvested, could form a valuable fuel. Trees and other plants absorb carbon-dioxide from the environment when they grow, so burning them doesn’t add in overall way to the green-house effect. They are carbon-dioxide neutral. And when these bio-power sources are used in power plants instead of fossil fuels, this leads to a reduction of carbon-dioxide.

Renewable energy is now entering the mainstream of British technology and society.

“We now have over 200 schemes, a wide variety of schemes actively under way, a 100 of them are already producing another hundred in course of coming into production. The government has indicated an intention to support more, and we have over a thousand enquiries from other generators, interested in getting into this area. I think renewable energy is on the increase, a part of the energy of the future”.

1. Why is the present a challenging time for energy industry?

2. What is the connection of environmental concerns and electricity production

3. What part of electricity requirements could be met from renewable sources by 2025? (Britain)

4. How much electricity is at present produced in Britain in coal-via-power stations?

5. How much electricity does Britain get from renewable sources at present?

6. What gives a real push to the development of renewable energy in Britain? What is the situation in Russia?

7. What are the ways of using the power of water to generate electricity in Britain\ Russia?

8. In what region do geo-thermal power stations function in Russia?

9. What are gaseous forms of pollution?

10. What are the advantages of generating electricity from bio-fuels and wastes?

11. What are the two ways of using the sun’s rays for producing electricity?

12. What wastes have a very high calorific value?

13. What fuel is carbon-dioxide neutral? Why?

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