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A NEW flue lining system will clean up Guernsey Electricity’s chimney from the inside.

Emissions from the Northside power station have been reduced by more than 80% since 2001, as a result of the submarine cable link.

This was confirmed by the 2005 Sustainable Guernsey Report, which attributed the sharp decline in local atmospheric levels of sulphur dioxide to the reduction in the burning of fossil fuels by the company.

However the intermittent use of the power station, which now supplies less than a fifth of the island’s electricity requirements, has increased corrosion within the 50 metre high chimney. Engineers are now working on a solution to the problem, which will involve relining the flue and installing a sophisticated infrasonic system.

Guernsey Electricity engineering director Steve Morris explained that the problem is caused by the stop-start use of the generators. This meant more moisture is now getting into the chimney, and allowing rust to form on the interior.

When a generator is switched on the flue heats up and causes the metal surface to expand. This can cause rust particles to be dislodged and expelled into the air, along with a coating of soot from inside the chimney.

Mr Morris said that these discharges were not a regular occurrence. However the company was aware of some instances where this had happened, and was therefore taking action to remedy the situation.

However he stressed the incidents that had occurred had not posed a risk to health. The particles were potentially corrosive on painted or metal surfaces, which had meant the company having to pay to clean up any property that had been affected.

‘Until now, whenever an incident has been reported which may have been the result of a discharge of soot from our chimney our policy has been to put right any problems caused,’ he said.

‘Although we believe that is the right thing to do, it is obviously not a situation that we are particularly happy with. As a company, we take our environmental responsibilities very seriously, and therefore wish to minimise the potential impact of any of our operations.’

Engineers are currently relining some mild steel sections of flue with a corrosion-proof, stainless steel tubing. An infrasonic system is also being installed, which will prevent particles from sticking together and forming deposits within the chimney.

All of the work is going on inside the stack. However a 75 meter crane, with a lifting capacity of 140-tonnes, is in place while engineers carry out the work. This is expected to take seven weeks.

The main contractor for the work is Wartsila Finland, with major subcontracts awarded to Swedish and Danish companies. However the new exhaust structures are all being manufactured by local company Marine and General Engineers Ltd.