![]() ![]()
Discuss this page on the Cyprus: the Environment Forum, open to all! Something you don't understand? Look it up on the Environment and Energy Wiki Encyclopaedia (beta version) The Environment and Energy Portal is now operational This site is now obsolescent and has been superseded by
|
Converting existing power stations Practically all of Cyprus' electricity is generated by oil-fired power stations. The total current capacity is about 1 100 MW and the peak demand approaches this value. This leaves insufficient reserve in the event of a major breakdown in hot weather, when the demand is highest. It is recognised that an increase of capacity is required within a few years. The average demand is increasing at a rate of nearly 10 per cent per annum while the rate of growth for peak demand is less predictable, because it is weather-dependent. If the peak demand exceeds the supply, the only solutions are either a 'brown-out' if the shortfall is small or regional black-outs. (A brown-out is where the voltage drops to about 210 V or less, a black-out being where the power supply is cut completely.) As Cyprus becomes more industrialised with greater potential tourism and homes are equipped with more appliances, the demand is expected to continue to increase over the next decade. More capacity is therefore very necessary. Ideally, the current structure could be complemented by an increase of the use of renewable sources (see the essay on Renewable Energy). It is doubtful whether these could provide more than an extra 50 MW, in the short term, mostly solar PV generation and by enhancing the value of waste. This would be useful as at least half of this would be generated when the peak demand is highest (unfortunately, though, the efficiency of solar panels drops when the temperature is high). If one or more waste enhancing power stations were built and the necessary collection infrastructure implemented, then the total capacity could be increased by a further 100 MW. This would have other environmental advantages. However, none of these measures will be sufficient in the long term (say, within a decade) and demand will outstrip the expected supply. It is therefore necessary to envisage the construction of new power stations. This is exacerbated by the requirement to reduce carbon dioxide emissions from current oil-burning ones (see the essay on Climate change). How can this be achieved? Converting existing power stationsThe ability to convert existing power stations from oil-burning is very limited. At the best, the more modern plants could be converted to burn methane (natural gas). This would reduce the carbon dioxide emissions by up to about 10 percent per kWh but at the cost of a significantly increased concomitant emission of methane at all stages of production of the gas. Because methane is a bad greenhouse gas, much worse than carbon dioxide, this would actually be environmentally negative (see the essay on natural gas). However, major changes to the thermal design of the plant would be necessary; gas is not a "drop-in" substitute for oil. Notably, the stack gases would contain much higher levels of water vapour. Other infrastructure changes would be the provision of high-pressure, insulated, liquid gas reservoirs at -164°C and the means of filling them from ships and from biological methane. Worse, it requires considerable energy to liquefy the natural gas and to transport it from the producer to this island, all of which will also come from fossil fuels and will contribute to carbon dioxide emissions. New power stationsNew power generating capacity must be built. The big question is what type? Natural gas-firedThis is the obvious and easy method, but there are four serious disadvantages that must be taken into consideration:
There are two kinds of gas-fired stations: conventional thermal types with a boiler driving a steam turbine and direct-fired gas turbines. The latter has the advantage that, in the event of a breakdown, a loss of wind or sun, or a sudden increase in demand, they can be brought on line in a very short time: this makes for the ideal back-up method without the need to idle conventional thermal systems. Planning applications have been made for an off-shore 200 MW platform power station to be built, close to Vassiliou power station. I must admit that the cost of this must be considerably higher than a traditional land-based one, which makes me wonder what the advantages could be, especially as the promoters state that LNG tankers would need to shuttle to it only once every 80 days. I also wonder whether it would affect the amenities in the Governor's Beach area. NuclearThis also suffers from disadvantages:
However, there also great advantages:
The choiceTaking the long term view, I believe that the most economical, environmentally sensitive and reliable choice is with a small nuclear power station. A capacity of 1 to 1.5 GW would cover the foreseeable needs of Cyprus for at least two decades and provide a degree of independence from politically unstable regions. The recycling of the fuel could be kept within the European Union (France) with easy means of transport. The actual cost of nuclear-generated electricity is typically towards the top of the same range as fossil-fuel-fired systems, so should not entail any great adjustment of prices. In fact, as the cost of oil and gas increases, so nuclear energy will become increasingly competitive. The holistic carbon dioxide emissions, including mining, purification and transport of the fuel is typically about 2 - 3 per cent of that from even the best fossil fuels:
Of course, this should be complemented by renewable sources, to a maximum possible. This maximum of variable methods is generally about 18 - 20 percent of the grid capacity, to ensure stability. At all times, the electricity from these sources should be used to a maximum and the shortfall be filled in, initially, by nuclear, then gas-fired, if the demand still exceeds the supply and, finally, oil-fired, only in an emergency. It should be remembered that Cyprus, unlike the rest of Europe, cannot supply a shortfall by importing electricity from other countries. In my opinion, this kind of scenario provides the best possibility for Cyprus' future. If the hydrogen-fuelled car becomes the norm, then a further 2 GW of generating capacity will be required (see the essays on Cars and Hydrogen). ConservationOf course, electricity should not be wasted. If it is, it is costly and polluting. It therefore behoves every user to use this source of energy as economically as possible. There are various ways of doing this:
ConclusionFuture electricity supplies in Cyprus are a thorny problem that cannot be resolved by half-measures. All parties, including the public, must take the bull by the horns. Conservation is important, as are renewable supplies, where these are feasible. Demand will foreseeably rise to over twice the current peak requirements within a decade, probably sooner. Decisions must be made as to how this will be done, even if they are unpopular. Further readingThe following three references are EU publications, impartially putting forth the advantages and disadvantages of nuclear power: The following summarises the problems and solutions for an "environmentally-friendly" supply of electricity:
|
Discuss anything related to this page at this forum. The opinions on this site are personal and do not necessarily reflect those of any third party. All information is given in good faith but no responsibility is taken for such information; any person or organisation using such information should ascertain that it is suitable for his/her/their conditions of use. No reproduction of the contents of part or the whole of this site may be made in any form without the written permission of the owner. An exception is made that a print-out may be made for one individual's private use without seeking permission; it is forbidden to make multiple copies or to photocopy a print-out. Links may be made to this site. Copyright © CypEnv 2004/2007
|