The scheme is also "demonstrably more economic" than putting the line underground, according to the would-be developers.

They warned that if parts of the line had to be buried, the whole scheme would have to be re-evaluated because of the extra costs involved.

The inquiry opened in Perth into proposals to replace the existing 137-mile electricity transmission line between Beauly near Inverness, and Denny, near Stirling, to help take power from planned renewable energy developments.

But the scheme by Scottish Hydro Electric Transmission (SHETL), a subsidiary of Scottish & Southern Energy (SSE); and SP Transmission, a subsidiary of ScottishPower, has met objections from the five planning authorities involved - Highland, Perth and Kinross, Stirling and Falkirk councils, and the Cairngorms National Park Authority.

More than 17,000 people have also protested and a number of campaign groups have been formed to fight the plans, claiming the new line will threaten health, landscape, tourism, wildlife and property values.

The proposed GBP 320 million, 400,000-volt transmission line would replace the 132,000-volt line. It would use about 600 pylons - some 200 fewer than in the one it will replace - but they will be more than 20 metres higher at 67 metres (200ft).

The inquiry's first witness, David Densley, SHETL's regulations manager, said the energy regulator Ofgem had considered the plan and seen it as necessary and economic.

He said the planned overhead route was demonstrably more economic than going underground, as campaigners are calling for.

Mr Densley said the electricity companies would recoup the cost of the upgrade over 20 years. However, if the inquiry reporters decided some or all of the line had to be put underground, the companies would have to return to Ofgem to seek approval for more funding.

He said that as Ofgem's main concern was to protect prices to customers, the regulator would be keen to cap the cost as ultimately this would find its way back on to electricity bills.

The inquiry is set to become the longest ever in Scotland, with 29 weeks set aside over the next 11 months, and will cost an estimated GBP 10 million.

The first eight weeks will be taken up with SHETL making the case for the upgrade. The inquiry will then move to Inverness in May and June; Kingussie in August and September; back to Perth during October and November; and then Stirling in November and December.

Before evidence started yesterday Colin Hood, SSE's operating officer, said

: "We believe (the plans) are strongly founded and will eventually receive the go-ahead. It is vital that they do, because the country's goals for greener and more indigenous sources of energy depend on it."

However, it has been claimed the inquiry will waste time and money and discredit the planning system.

Highland Council has questioned whether communities and pressure groups will be able to attend much of the inquiry and be properly represented.

(c) 2007 Scotsman, The. Provided by ProQuest Information and Learning. All rights Reserved.

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