By JOHN ROBERTSON
INVESTIGATIONS are taking place into building a new power station on a site further out of Lerwick because the existing one at Gremista will struggle to meet more modern pollution standards.
Scottish and Southern Energy is currently assessing a range of possible options for the period after 2010 to put before the electricity watchdog Ofgem for approval.
A new plant will be required even if Viking Energy succeeds in building its massive windfarm because energy regulations dictate that there should be security of supply, and the possibility of a failure in the proposed interconnector cable between Shetland and the mainland which is it hoped might supply the islands with power from the National Grid when there is little or no wind must be factored in.
It could work out cheaper to build a modern new plant from scratch on an out-of-town site than to clean up old plant and renovate or replace ageing generators, some of which will soon be 40 years old and were due to be retired back in 2000. Such a multi-million pound development would free up a large area of prime waterfront land to be cleared for new ventures.
According to local sources Scottish and Southern Energy representatives have been seen looking at possible new sites including areas around Rova Head, where the former SIC dump and incinerator used to operate. Another likely option might be the Dales Voe base which already has a quay fuel tankers could call at.
Most of the land in that area north of town is owned by Lerwick Port Authority which might be able to strike a reciprocal deal with Scottish and Southern to gain itself the current power station site – the elusive piece in its jigsaw of harbour redevelopment land stretching from the town centre to Greenhead.
The environmental regulator Sepa might also have good reasons to encourage such a giant industrial plant to flit from town to countryside.
On Wednesday, Lerwick Port Authority confirmed it had taken part in initial discussions with SSE during its evaluation of its options and expressed interest in helping the company find a new site on the authority’s land to the north of Lerwick. Chief executive Sandra Laurenson admitted the authority’s interest in acquiring the existing waterfront site “if it became available”.
She did not have specific plans for the site but added: “It’s a piece of waterfront estate so in the fullness of time the port authority would always be keen on land next to the sea for future quay developments.”
An SSE press spokeswoman confirmed a new power station was one of a range of options currently being assessed. She stressed no project had been settled upon at this stage and no contracts had been signed. “It’s not at that stage yet.”
The process is part of Ofgem’s so-called distribution price control, which requires power companies to provide it with five-year plans for approval. The next one from Scottish and Southern is due in December next year and the spokeswoman expected big decisions to be made late next year.
“We’re in the process of looking with Ofgem at how we continue to secure the supply to the Shetland Islands. As part of that we’re looking at the whole range of potential options, one of them being a new power station. But at the moment, until things are firmed up and we understand whether it’s a viable option, it is not a done deal.”
She said plant throughout Scottish and Southern’s network was obviously getting older and coming to the end of its life. “Lerwick is getting to that stage but it’s not there quite yet. Obviously we will look at the age, how it is working, the emissions etc.”
It might come as a surprise to some that a new power station is being contemplated at all, given Shetland is looking to generate 10 times its electricity needs at the Viking windfarm and also to import energy from the National Grid through an undersea cable when the wind isn’t blowing.
But full back-up will always be required in the islands, possibly kept in mothballs in case of a cable breakage or other technical failures, which effectively means a power station capable of generating Shetland’s full needs will have to be kept ready at the flick of a switch.
It is not known at this stage what options for powering a new station are being considered by Scottish and Southern. The existing 66 megaWatt plant is fed on heavy fuel oil – like ships’ bunkers – and medium fuel oil. Contrary to popular belief, the only use of diesel (or light fuel oil) is to start the big generators. Alternative fuel sources for a new power plant could include biofuels, gas or diesel.
Lerwick Power Station’s A station started life in 1953 and was joined in 1996 by the B station. But the set-up is inefficient. According to a report by the district heating scheme company Sheap, a shocking 60 per cent of the energy from burning fuel oil in the generators is “dumped” as waste heat into Lerwick harbour and the air above Gremista. If accurate, Sheap said the amount wasted is “many times” what the SIC’s waste-to-energy incinerator is able to produce in heat from burning the rubbish from Shetland, Orkney and offshore platforms.
Scottish and Southern was originally an equal partner in the district heating system, which was going to take waste heat from the power station generators. But the liaison fell through for technical reasons. The scheme was designed so the power station could opt in at a later date but it never happened.
Last week Sheap manager Neville Martin said: “It must be the only power station in the UK with a district heating scheme on its doorstep.”
In recent weeks SIC councillor Jonathan Wills has complained several times about the power station dumping heat. “It seems ridiculous to pour money into Lerwick harbour,” he said to fellow councillors.
However, Sheap now actually does not want the heat for several reasons, the main one being uncertainty over the power station’s future, which could see them come to rely on a heat source only for it to disappear within a few years by being mothballed. The heated water is also actually not very hot compared with what the system gets from the SIC waste incinerator.
In a separate development, Scottish and Southern applied to the council last month for permission to site the six big diesel storage tanks it has dotted around the power station. The retrospective application results from legislation passed in recent years requiring fuel tank owners to gain hazardous substances consent.
The tanks contain heavy, medium and light fuel oil for the nine engines and two gas turbines in the two power station buildings and they range in size from one that can hold 3,800 tonnes of heavy fuel oil to small ones holding 300 tonnes. There is also a number of small tanks holding chemicals and lubricants, making a total of up to 12,752 tonnes of oil on site.
The bulk fuel arrives by marine tanker at Holmsgarth to be pumped via a pipeline running from the quayside next to NorthLink’s car park, along the side of the main road to the power station tanks. There was a tanker in this week, the Sea Dweller, which arrived from Grangemouth on Wednesday. Scottish and Southern buys its fuel from various sources on the open market wherever it gets the best price. Its spokeswoman said the company did not discuss the matter publicly.
In the tanks application Scottish and Southern’s Shetland manager Bob Kelman stated: “This process and plant have been running at this location for in excess of 50 years using these fuels which help provide a lifeline service to the island community.”
John Holden of the SIC planning division said it was essentially a “catch-up exercise” which was taking time to fall into place. Last year GB Oils got consent to keep its seven fuel tanks at its North Ness depot for a further three years despite facing strong opposition from local residents worried about a possible explosion. Early this summer Peterson SBS applied for consent for its marine gas oil tanks at the Greenhead Base.