There aren’t a lot of windmills in South Yorkshire. Until the demise of the mining industry in the 1980s, coal was the traditional source of power round here, and in Royston, near Barnsley, the old colliery buildings are still visible on the horizon. But now a new landmark has appeared on the village skyline - a small, three-sailed wind turbine that turns slowly above the rooftops of the town’s secondary school.

Royston’s windmill is the most striking feature of a renewable energy project started several years ago by Ken Dunn, the school’s development manager. When he arrived as head of geography in 1994, the village’s reason for being there - the coal mine - had gone and the disused pithead winding gear loomed like a question mark over its future. But as Ken looked out on to the courtyard outside his office, he saw an opportunity to reinvent the area’s association with power.

Most people who are thinking of improving a patch of ground with a bit of a garden might think of including a water feature. But Ken had bigger ideas. “I thought what I would really like to have would be my own river.” So he built one.

Royston school’s river starts in a mountain tarn, tumbles down as a mountain stream, courses along a steep-sided valley and, through lowland, meanders out into an estuary. It runs in a wide loop round the courtyard, and is planted with species typical of each environment along the way. But it’s more than just a fancy rockery - it’s also a hands-on teaching resource and energy-saving system. Varying grades of stones can be added to the “riverbed” to mimic the effects of erosion, transportation and deposition, and the slopes are used to explain what contours represent on a map.

The windmill stands in the centre of the courtyard, powering a pump housed in a wishing well that carries the water back up to the tarn. The 225-watt windmill is supplemented by two solar panels mounted on a south-facing wall of the courtyard, which between them can generate another 60 watts of electricity. Far from being an expensive burden on the school’s resources, the windmill and river system are self-sufficient.

This innovative scheme has won several thousand of pounds in environmental awards and sponsorship from local engineering companies impressed by the school’s commitment to renewable energy. Although the low output prevents it from being connected to the school’s main electricity supply, there are plans to rig up a separate lighting system so that the excess electricity generated is not wasted.

“The thing that really frustrates teachers is they get a good idea and then they’ve got no money to make it happen. We are showing that renewable energy has a place in schools,” says Ken.

The school has a popular environmental group whose members give up their dinner and playtimes to collect waste paper, glass and plastic for recycling; Barnsley council pays pound;35 for every tonne they collect. Pupils enthusiastically recycle their soft drinks cans in a crushing machine in Ken’s classroom. Aluminium commands a good price - about pound;600 a tonne - so the crusher has paid for its initial pound;200 cost many times over. “Every school should have one,” he says.

The greening of Royston school has also seen a willow plantation spring up in a corner of the school fields; the quick-growing shoots will be used in a willow sculpture. Ken has also overseen other environmental improvements. The lion which stands guard outside the school’s reception was carved by a chainsaw artist from an old ash tree felled in the grounds. And old tennis courts have been resurfaced as an all-weather, multi-purpose sports pitch, thanks to a deal with a local manufacturer.

In keeping with the green adage to “think global, act local”, pupils are now hoping a village in Africa can benefit from the technology on their doorstep. The link with Malealea in Lesotho began by chance when Ken won a trip there in a photographic competition. He saw how reliance on wood burning for cooking and heating had led to deforestation, and had an idea - to bring electricity to the village by way of a wind turbine.

Pupils are raising money to buy one and have made pen pals at Makhettheng school in the village; their letters and photos decorate the wall. “The kids learn about another community - it is hugely enriching for them,” says Ken.

“When I started this project I had three aims - to create a learning landscape, to reduce the waste produced by the school, and to reduce the energy the school uses. The whole idea is to show students that energy is not just the black stuff that this village was built on.”

Thanks to his energy and enthusiasm, the children of Royston school are now seeing far beyond the familiar landscape of their home town.

The Growing Schools garden is part of a government initiative called Growing Schools which was launched in September 2001 and is supported by a pound;500,000 grant from the Department for Education and Skills. The initiative aims to increase pupils’ understanding and involvement in outdoor education by funding visits to farms and environmental centres, developing school grounds, and promoting healthy lifestyles. Further projects are planned for the next two years. For details go to www.growingschools.org.uk or www.schoolsgarden.org.uk