In the warm light of a summer’s afternoon, the rays forcing their way through windows half-covered with cobwebs, Brian Shingler puts his shoulder to a large iron wheel and begins to turn it. As he does so, above our heads, cogs meet other cogs, huge crank shafts turn and, suddenly, below the wooden floor on which we stand, a low rumbling begins. Unseen, water is rushing through massive pipes housed in the deepest depths of the building; water that once powered the grinding of corn and barley, but now generates a new crop: electricity.

Gants Mill, a four-storey water mill on Shingler’s farm near Bruton in Somerset, dates back to the 12th century, but it is the vanguard of a new wave of old water mills recommissioned to cater for the 21st-century need for renewable energy sources.

“I was brought up here,” says Shingler proudly, looking around the ancient room. His father bought the mill with the farm in 1949, using the mill to grind meal for their sheep and chickens. In 1979, Shingler and his wife, Alison, took over the farm, by which time the mill had fallen into disuse and disrepair.

“Then, in 1995, we decided to restore the mill building. We got a grant from English Heritage to do it, but on the condition that we would allow the public to visit. When people started coming, they would say, ‘It’s lovely, but why aren’t you using the water power? You could generate your own electricity.’ But we knew the cost of putting in the system would be high and, back then, electricity was cheap, so it wouldn’t pay for itself very quickly.”

Since then, however, the government has become very interested in renewable power and has put in place schemes that guarantee a demand and a price for green power.

“Yes, we were a little bit altruistic in terms of trying to reduce greenhouse gases and so on,” says Shingler, “but our main motives were to reduce our energy costs, make a bit of money and use the mill again.”

Alison says: “We used to look at the mill and think there was something lacking. It was a historic place, and it should be working again. But we weren’t sure how we could afford it.” And it wasn’t just expensive — it was a project that sometimes seemed to take over their lives.

“If we knew then how hard it was going to be,” admits Shingler, “we would probably have thought twice about it. Some things were so tough and took so long — like getting the abstraction licences for the water, which really just allow you to use it.”

Adds his wife: “It’s not as if you’re actually taking it away — you just take it out of the river and then put it back where you got it. But the length of the forms we had to fill out — and the time it took to get a decision ... They treated us just the same as the local power station!” The new machinery was finally installed two years ago. Depending on the rainfall, the Shinglers now make a little under £3,000 each year from selling the power to the national grid. Because they got help from government agencies to install the new machinery, the mill will have paid for itself within six years.

The Shinglers are now in very good company. Last month, the Queen — who is installing a borehole to supply heating — was granted planning permission to construct a hydropower plant on the Thames that will supply about a third of the electricity used by Windsor Castle. In Britain, there are about 40 micro hydropower generators (those supplying 100kW or less).

Water mills have been in existence in Britain for more than 1,000 years; many are listed in the Domesday Book. They had their heyday during the Industrial Revolution, when the textile industries in the Midlands relied on this form of power. The legacy is up to 20,000 old water mills dotted throughout the country. Until a few years ago, they were seen as little more than an attractive reminder of our industrial heritage, but accelerating government commitments to green energy have made recommissioning these mechanical monoliths economically viable.

Mill owners are guaranteed a demand for their power and can also apply for grants worth up to £5,000 from the Clear Skies initiative, funded by the Department of Trade and Industry, for equipment and installation. Once installed, the mill’s mechanics are generally low-maintenance and should last about 25 years.

For a medium-sized mill with most of its original mechanics still in place, recommissioning could cost in the region of £20,000-£40,000. Most mill owners take in something between £3,000 and £10,000 per year by selling electricity, depending largely on how fast their river flows.

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