UK experiences first major solar eclipse for 16 years

Britain's first big solar eclipse for 16 years was under way on Friday, leaving commuters to make their way into work under darkened skies.

Watchful electricity grid operators, expectant scientists and excited schoolchildren will already have seen the beginnings of the eclipse as a sliver of moon began to pass between the earth and the sun at around 8:30am.

The eclipse is expected to peak at about 9:30am and wind down at around 10:40am.

Solar eclipse in Australia, November 14, 2012
Greg Wood | AFP | Getty Images
Solar eclipse in Australia, November 14, 2012

The eclipse will be total to the north of the UK, in the Faroe Islands and the Svalbard archipelago. In Britain, the best views will be seen by people in the north, where the sun will be almost completely obscured. But even in London, around 85 per cent of the sun will be covered at the peak of the eclipse, and there will not be another chance to see one of this magnitude until 2026.

The event will be closely monitored by grid managers. In 1999, which saw a total eclipse over southwest England, a solar panel was a rare sight on a British roof or field. Today there is more than 5,000 megawatts of solar generating capacity, more than from Yorkshire's huge Drax power plant, the country's biggest.

Other nations, such as Germany, have almost eight times as much solar power, and Europe's electricity system operators have given warning about the prospect of disrupted supplies during the eclipse.

Up to 35 gigawatts of solar power, the equivalent of about 80 conventional power stations, is expected to fall off the European grid during the event, according to Frost & Sullivan research analysts.

The UK's National Grid will be working with its counterparts on the continent to ensure supplies are maintained, but says it is well-prepared.

"We are in a slightly different position to some of our counterparts in Europe, owing to our particular generation mix," said the Grid, explaining that it was expecting a loss of 850 megawatts of solar power from the system.

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This should be more than offset by a 1,100MW drop in demand for electricity as people go outside to watch the eclipse.

"This loss of solar is entirely manageable," said Jeremy Caplin, forecasting manager at National Grid. "We started planning for this in May last year."

If there is bad weather, even fewer people will be watching and there will be less solar generation lost.

The prospect of cloudy skies is a worry for scientists and thousands of children who will be monitoring the event. Watchers were advised to take to the hills to secure better views.

"The weather is the villain of the piece in eclipses," said Professor Giles Harrison, head of the University of Reading's meteorology department.

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He is leading a national experiment involving nearly 200 schools and specially deployed weather balloons around the country that will try to detect phenomena such as the "eclipse wind", or changes in the breeze anecdotally reported during an eclipse.

Scientists hope the information gathered will help to boost understanding of how the weather works so that forecasts and even climate change models can be improved.

Medical experts stress that it is dangerous to look straight at the sun during an eclipse, even with sunglasses.

The Royal Astronomical Society has produced a booklet on the best way to watch it safely, and says the simplest method is to use a kitchen colander and a piece of paper.

By standing with your back to the sun, you can hold the colander in one hand and the paper in the other and safely see images of the eclipse as it passes.

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