The Marsa power station's largest turbine, an important cog in energy generation, has been in service for half a century and its operational lifetime expires next year.

According to information obtained from Enemalta's Electricity Generation Plan, the 60-megawatt turbine was commissioned in the UK in 1959. Malta bought it second hand in 1987 and refurbished it in 1996 to extend its lifetime by another 15 years. It has an efficiency rating of 29 per cent.

The lifetime extension ends in 2011, which does not bode well for security of supply in the next couple of years until the new Delimara power station extension is built and the cable interconnector with Sicily is up and running.

However, the turbine is not Enemalta's most ancient relic. Three 30MW turbines at Marsa are 58 years old and were commissioned in Palermo, Sicily in 1952, just seven years after the end of World War II. They were bought second hand and installed at Marsa between 1982 and 1984 and their efficiency is rated at 25 per cent.

Not far behind are another two 30MW steam turbines installed in 1970, making them 40 years old.

The youngest turbine at Marsa is 20 years old and was installed in 1990 with a capacity of 37.5MW. It is an open cycle gas turbine that operates on diesel.

Marsa is an aged plant by all counts and should be phased out before 2015. However, a number of turbines at Delimara power station, which came on line in 1992, are already half way through their operational lifetime, according to the Electricity Generation Plan drawn up in 2006.

Two 60MW steam units at Delimara are 18 years old and were the first to be commissioned when the new power station was built. Another two 37.5MW gas turbines are 15 years old while the biggest unit, a combined cycle plant producing 110MW, is 12 years old.