Tag: energia

They have been dubbed Britain’s “industrial soldiers”, marching across hill and valley since before the second world war to carry the national grid’s 400,000-volt power lines. But the government is calling time on the 84-year-old design of the electricity pylon, with a competition to find a more attractive 21st-century alternative.
The National Grid and the energy and climate change secretary, Chris Huhne, are calling for ideas for pylons to carry electricity from a new generation of nuclear power stations and windfarms across hundreds of miles of British countryside.
Sir Reginald Blomfield’s resolutely practical 1927 lattice-tower design is said to be unsuitable to carry higher loads from the new power stations and the government and the National Grid are also hoping a sleeker, more elegant design could head off public anger at new pylons and high-voltage cables planned to serve a 10-fold growth in electricity from wind power and up to 10 new nuclear plants.
About 80 miles of high-voltage pylons are planned in the Lake District, 50 miles in Snowdonia and 30 miles in the Mendip Hills in Somerset, according to calculations by the Campaign to Protect Rural England (CPRE).

Huhne’s call to “ignite creative excitement” and “seek the most acceptable ways of accommodating infrastructure in our natural and urban environments” comes as more than 1,500 people from Montgomeryshire prepare to descend on the Welsh assembly on Tuesday to protest against a 30-mile, 400,000-volt link taking energy into Shropshire from up to 800 wind turbines on Welsh uplands. Glyn Davies, Conservative MP for Montgomeryshire, claimed the proposal would “completely dominate the area” and endanger its tourist industry.
In Lancashire, residents are fighting plans to link Irish Sea wind turbines to the urban areas of the north-west by putting pylons through beauty spots including the Trough of Bowland. A Ribble Valley councillor, Ken Hind, has said the scheme has “a Day of the Triffids feel to it” and scoffed when he heard about the design competition.
“How do you disguise a 50-metre pylon?” he said. “Paint it green, put camouflage on it? We don’t want this to happen in areas of beautiful countryside. It is a form of environmental savagery. Yes, we have to keep the lights on, but we have to realise there is a price to pay for protecting the countryside and that is burying the cables.”
National Grid estimates that running the cables underground costs £15m to £20m a mile, 10 times more than using pylons, and require excavation of a strip of land as wide as a dual carriageway. A CPRE report says that experience in Denmark suggests it could cost £6m a mile to lay an underground cable.
The National Grid’s executive director, Nick Winser, says it is keen to support the development of the most visually acceptable overhead solutions. “The pylon has served the nation well, but new technologies and materials mean there may now be opportunities for new designs.”
Coal-fired power stations that meet one fifth of Britain’s peak demand will close by 2016 and nuclear power stations providing an eighth of peak demand will also go off-line. To replace them, the government plans to build onshore wind farms providing 20 gigawatts of power and enough off-shore turbines to provide 33 gigawatts by 2020. It has also identified 10 potential sites for new nuclear power stations.
A spokesman for the CPRE, Jack Neill-Hall, said it accepted that new power lines would be needed, but believed it was economically viable to run the lines underground or under the sea, preventing disfigurement to the landscape. “Although a less intrusive pylon design would be welcome, the real focus should be on how we can get pylons out of our national parks and other valued landscapes,” he said.
Attempts to redesign the pylon are already under way in Iceland and Italy.
Iceland’s national grid company ran a design competition last year in which entries included pylons reconfigured to look like giants striding across the landscape holding power cables in their hands. Another, whose designers were said to be inspired by a recent viewing of The War of the Worlds, had cross bracing like curved bones.
A Paris-based British designer, Hugh Dutton, won a competition for the Italian energy company Terna with slender Y-shaped pylons inspired by the first tender shoots of a young plant. The first prototypes are set to go into production soon. He said creating a more positive image for pylons to try to head off local opposition was a key concern for clients, but added that his more elegant design was more expensive.
“Traditional pylons are the very symbol of insensitive intervention of mankind on the landscape,” he said. “These industrial soldiers that march across the countryside, galvanised steel trellis towers, are certainly optimal and efficient structures, but lack poetry.”
In 2000, Lord Foster designed a pylon for Italian utility Enel that looked like a gymnast standing with arms aloft.
His practice explained that the design “abandons the conventional and untidy ‘Christmas tree’ configuration in which cables are supported by arms sprouting at intervals from the pylon’s main mast. Instead the cables are neatly grouped within an open V-form, created by the junction of two attenuated masts”.
National Grid said the winner of its competition would be announced in October. It would try to make a “system-compliant” version of the winning design and offer it as an option for future power lines.

Fonte:

Guardian