New lines from north to south are being planned

The regulator Ofgem has drawn up its preliminary plans for a cash deal to pay for a lift to the country's transmission network.

All but �10m will go towards power lines between Beauly in the north and Denny in central Scotland, if planning permission is granted.

The rest could go on improving the link between Scotland and England.

The move is aimed at cashing in on the potential of renewable energy.

Deputy Enterprise Minister Lewis Macdonald said: "This is a clear green light from the regulator for the network upgrades required to fully exploit Scotland's green energy potential.

"Upgrading the electricity grid is essential if the renewable sector is to reach its full potential and we have continually pressed the regulator for progress to take this vital work forward."

New mechanism

Ofgem chief executive Alistair Buchanan added: "To avoid any possible delay, Ofgem has acted now to propose a new mechanism to allow investment for network upgrades to support the growth in renewable generation."

The investment announcement was made as ScottishPower revealed it had increased its client base by 250,000 more customers.

The company said the gain was made in the three months to 30 June.

However, energywatch Scotland, the independent gas and electricity watchdog, called on the firm to celebrate its improved performance by rewarding its loyal Scottish consumer base, who it claims pay �100 more in some cases than customers in England.