Conventional electricity

Practically all of Cyprus' electricity is generated by oil-fired power stations. The total current capacity is about 1 300 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 or if there is a breakdown in generating capacity or distribution, 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 stations

The 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 -164Â°C and the means of filling them from ships, along with capitally expensive regasification plants. Alternatively, compressed natural gas has been suggested, but this seems even less viable, although at a better scale for the island. Biological methane would seem even less likely to be useful. Worse, it requires considerable energy to liquefy or compress 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 stations

New power generating capacity must be built. The big question is what type?

Natural gas-fired

This is the obvious and easy method, but there are four serious disadvantages that must be taken into consideration:

natural gas combustion produces carbon dioxide emissions, responsible for climate change. For each kilogram of natural gas burnt, nearly 2Â¾ kilograms of carbon dioxide is emitted.
tthe supply of natural gas is limited, the bulk coming from politically volatile Middle and Far Eastern countries and Russia: supply is therefore impossible to guarantee and the price is sure to rise drastically as reserves dwindle and as oil becomes scarcer
supply is dependent on special tanker ships, which are limited in number
natural gas is inherently a bad greenhouse gas and emissions from the wellhead to the power station are inevitable

TThere 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 advantages that they are more efficient and, 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 assiliou 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.

Nuclear

Conservation

Of 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:

use low-energy light bulbs
switch off lights when not required for more than 3 minutes
switch off all appliances not in use
keep constant room and water temperatures but switch off at night
set the thermostat of immersion heaters to 50 - 55Â°C
ventilate rooms minimally
ffor electric room heating, use the air conditioner in 'heat' mode to rapidly bring a room up to a comfortable temperature, rather than a fan convector or heater
consider night-storage heaters rather than fan convectors or other heaters (these have the advantage that they 'burn' electricity when the supply is much greater than the demand and the power stations are producing their background levels of emissions; the extra load makes almost no difference to the pollution. The cost of energy is also reduced on Tariff 55.)
consider heat pump central heating.
run irrigation pumps at night (this also conserves water)
use thermostatted electric heating to a maximum of 20Â°C in living rooms and 18Â°C in bedrooms
use thermostatted air-conditioning to 28Â°C in summer for only a minimum time
improve house insulation
purchase low-consumption appliances

Conclusion

Future 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.

Electricity