By Costis Stambolis
The Greek power system is under huge strain from skyrocketing numbers of airconditioners. Temporary power outages are already a fact of life, but a major nationwide blackout could be just around the corner if more energy production capacity isn’t created.
Such a scenario has so far been avoided this summer through preemptive action by HTSO, Greece’s electricity distributor, which cut the electricity supply in different areas of the country on a rotating basis, especially in suburban areas of Thessaloniki and Athens. So on July 23 and 24, whole towns and selected blocks in large cities were left without electricity for several hours.
The problem is that during the hot summer months, especially during periods of intense heat with temperatures reaching as high as 45 and 46C, peak loads rise as the result of large-scale use of airconditioning units.
Following a heatwave in the summer of 1987 when as many as 1500 people lost their lives, airconditioning started becoming norm in many houses and businesses. However, a large majority of airconditioning units installed in Greece are energy-hungry. Most units sold in this country lack power condensers, which sharply reduce electricity demand, but raise the cost of the unit.
With approximately 400,000 new airconditioning units being installed in the country every year, there is a sharp increase of unpredictable peak loads each summer. The system cannot cope, making the threat of a countrywide blackout very real.
The demand for electricity from the grid – which is run by the state-controlled Public Power Corporation’s (PPC) – hit a new record on July 23, as the country sweltered in very hot weather conditions that were not expected to ease up until the end of the week.
Demand in the PPC’s power network hit 10.610 MW at 2.10 p.m. on July 23, beating the previous record of 10,512 MW set on June 27- during a previous heatwave that killed 12 people.
Demand for power in the Athens region was slightly lower than that recorded at the end of June, which reflects the large number of residents that have left the city for their summer vacation.
HTSO confirmed that the power grid managed to meet the surging demand after controlled power cuts in PPC lignite mines, irrigation networks and a number of industrial areas.
Greece is not the only country that faces such extreme weather conditions each summer. In many other places – like Australia, Spain and California, where electricity systems are also under strain – a large variety of peak load saving measures have been introduced with quite impressive results.
Evangelos Lekatsas, chairman of HTSO, tells the Athens News that the problem with the Greek electricity system is clearly due to peak loads and these have to be addressed with more demand-side management measures, such as increased electricity rates for the 200 peak summer hours, rather than through an increase in power generation.
But that idea has been consistently vetoed in favour of artificially low electricity rates.
This is not to say that additional capacity is not required. With 12,500 MW installed capacity in the interconnected grid and peak loads now reaching 11,000 MW, it is clear that the Greek system falls far short of the industry standard of 15 percent spare capacity. Out of some 30 large base load thermal power plants, it is normal that three or four of them – corresponding to 1,000-1,400 MW – may be out of service due to maintenance or repairs at any one time.
Every year, Greece is obliged to import enough electricity to cover shortfalls from neighbouring countries. The precariousness of that system became apparent on July 24, when power systems in Kosovo, Montenegro and the Former Yugoslav Republic of Macedonia collapsed, abruptly cutting more than 1,000 MW from the Greek system. That led to a blackout in Thessaloniki and the surrounding area for several hours.
However, critics say the government has failed once again to predict actual needs and has mismanaged completely this aspect of grid requirements. They point out that Greece has failed to commission, let alone build, a single new large power plant over the last three years.
(Athens News, 27/7/07)