13 October 2011 Last updated at 11:08 ET

Work to restore power after fire at Winster

People have been warned to use their electricity sparingly and be prepared for some further disruption

Thousands of homes and businesses in Derbyshire were left without power overnight after an explosion at an electrical substation.

The station at Winster, near Matlock, was damaged on Wednesday afternoon and more than 30,000 properties in Matlock, Darley Dale and Cromford were affected.

By Thursday morning about 5,000 customers were still without power but this was restored by about 16:00 BST.

Western Power Distribution said it was investigating the cause of the blast.

Environmental impact

Simon Pett, from the company, apologised for the disruption and said engineers had been working round-the-clock to get the supplies back on.

Mobile generators are being used to supply power in the area

Western Power Distribution has brought in mobile generators from across England. It is estimated repairs to the substation will take until at least the weekend.

In the wake of the explosion, traffic lights in the area stopped working, causing some road disruption. Extra police patrols were also put on after street lights failed.

Several major buildings such as County Hall and the newly-opened Arc Leisure Centre in Matlock were blacked out after emergency generators ran out of fuel.

Centre manager Paul Blakemore said: "Our emergency generators came in and we made some phone calls, hoping the power would come back but we lost all power after about three hours.

"This has meant we had no option but to remain closed [on Thursday morning] which is obviously disappointing for our users."

Residents who had their power restored earlier were asked to use it considerately so the temporary supply could cope.

The Environment Agency said it had attended the scene to ensure no cooling oil from the substation - or foam from firefighters - leaked into water courses.

It said it would also be checking local pumping stations to ensure they were working correctly.