The full solar eclipse on Wednesday evening could pile pressure on already struggling power systems across Europe.

Experts say a dip in solar power because of the eclipse could affect the electricity grid which has suffered because of this summer’s extreme weather.

Heatwaves have forced nuclear and coal plants to switch off across the continent and low water levels have halted hydropower stations. 

Grid operators in France and Spain are expecting solar power production losses and stand by to balance the system from other power sources.

Spanish grid operator Red Electrica says the eclipse could reduce Spanish solar power by up to 5GW – equivalent to 13 per cent of maximum demand for a typical Wednesday in August.

In Britain, the National Energy System Operator says solar output is likely to drop by up to 1.3GW, comparable to losing the output of two nuclear reactors.

The first eclipse visible in Europe this century will start in the UK just after 6pm. It will not happen again until 2081. In much of the country, the eclipse will exceed 90 per cent, meaning the Moon will obscure more than nine–tenths of the Sun.

It will be the most complete eclipse here since August 1999 when darkness fell across the UK in mid–morning. 

This time, people in the West and South West will see more of the Sun obscured, with 95 per cent blocked in Plymouth. 

London will see a 91 per cent eclipse but the figure drops to 88 per cent in Shetland.

In north and east Spain, the Balearic islands and north–east Portugal, the eclipse will be total, completely blotting out the Sun for more than two minutes.

Nightclubs in Ibiza are gearing up for ‘the party to top all parties’ as the total eclipse draws near.