The perfect afternoon was cold, windy and gusty to officially unveil one school's 40ft-high "big toy".

The name was given to Winscombe Woodborough Primary School's new wind turbine by Weston-super-Mare MP John Penrose when he explained its purpose to pupils on Friday afternoon.

The Conservative MP then unveiled, in the school's corridor, an electronic score board constantly updated with the turbine's statistics.

He said: "This is a great day and a wonderful idea and I'm delighted to declare this thing open to see how much electricity is generated."

The £31,000 electricity generator was paid for by grants and in the first 11 days in operation had generated 151 kilowatts – saving the school £10 in electrical costs.

On average the turbine is expected to generate about five kW per hour when the wind blows at eight miles an hour or higher – enough to light the school's main hall lights for two-and-a-half hours.

"It's a good start," said headteacher Linda Grogan. "It's not just about the saving but getting the children to learn about carbon footprints and emissions."

The turbine is about seven times the height of an average British man and is located in the distant corner of the school's playing field. When the wind was at its peak on Friday afternoon the noise created was minimal.

Mrs Grogan said one neighbour had been unsure about the turbine when plans were submitted but no more had been heard and lots of people had congratulated the school on its new addition.

"Someone even sent a card to the turbine welcoming it," said the headteacher.