The power of the River Wharfe – first tapped by Burley-in-Wharfedale mill-owners in the 18th century – is to be harnessed once more to provide green energy.

A £1 million-plus hydro power scheme at the former cotton spinning mill Greenholme Mills will be officially unveiled by MP Philip Davies next week.

A joint venture between Derwent Hydro and TLS Hydro, the new plant, providing enough environmentally-friendly electricity to power 340 homes a year, will open its doors to the public between 11am and 1pm on Saturday, August 20.

The plant’s new Kaplan turbine can process ten metres-cubed of water per second, and it is said it will save the equivalent of 645 tonnes of carbon dioxide being relased into the atmosphere a year from an equivalent fossil-fuelled power station.

Green energy may be a fast-growing modern trend, but using the power of the river is nothing new. Water from the Wharfe was the key to cotton spinning operations at the location from the late 18th century.

Greenholme Mills grew to be hailed as the largest water-power scheme in England, and continued to use hydro-electric power after similar manufacturers had switched to other sources. It traded until the 1960s.

The mill that still stands was built in 1819, and the hydro scheme uses an old mill leat – the channel taking water out of the River Wharfe into the turbine.

The electricity it produces will be sold to independent British renewable energy supplier LoCO2 Energy. The company relies on projects like Greenholme Mils to buy electricity for its customers.

Members of the public will be able to get a closer look at the workings of the hydro scheme at the open day, and talk to engineers and other members of the team behind the project.