Eureka! How Archimedes and his 2,000-year-old invention will help provide green energy



A device invented more than 2,000 years ago by Archimedes has found a 21st century use - generating 'green' electricity.



A crumbling 99-year-old hydroelectric plant in the Yorkshire Dales will come out of retirement thanks to the Ancient Greek's genius.



Key to the English Heritage project is the adaptation of Archimedean screws to operate turbines.



The screw was designed to carry water upwards as it rotates, but the project at the Linton Falls plant has reversed this principle.



The river Wharfe will flow down through two screws, spinning them fast enough to generate enough renewable and clean energy to power 100 homes.



Archimedes of Syracuse (287-212 BC) has been credited with inventing the screw to remove water from the hold of a ship.



The revolving screw-shaped blade inside an angled pipe was turned by a handle, scooping up water and carrying it to the top.



The same technology has been widely used to pump water from low-lying rivers for crop irrigation, as it is still used in the Nile delta in Egypt.



The method is also used to drain flooded fields, move grain in mills and powders in factories.



The tiny Linton Falls plant was built in 1909 to bring the first electricity to the village of Grassington, but has been out of action since 1948.



Since then it has been protected as a scheduled monument because of its historical significance.



By next summer it should once more be generating electricity for the National Grid.



It will produce 510,000 kilowatt hours of electricity a year, saving around 216 tons of carbon dioxide emissions compared with fossil fuel generation.



The scheme's cost has not been revealed. 'Archimedes should be pleased,' said Austin Flather, the project manager.



'There is sometimes a feeling that technology is everything and we must always be striving for the latest developments. But quite often the older, tried-and-tested methods are just as good, if not better.



'I think if he saw us using his technology this way he would smile. Frankly it is not highly sophisticated - which is a good thing. It's easier and cheaper to build, maintain and operate than more modern systems.



The 100-year-old defunct hydro plant at Linton Falls is to be refurbished and put back into use to create green power

'Also, circumstances are changing and this kind of smaller installation is becoming viable where it would not have been just a few years ago. It fits with the government requirements for green renewable energy technology. This method takes nothing away from the river, nor adds anything to it.'



The Yorkshire Dales National Park Authority is considering up to 50 sites for small hydro-electricity schemes.



Chief planner Peter Watson said: 'This project brings together two vital characteristics of the National Park - the protection of its cultural heritage and the promotion of new technologies to meet the climate change challenge and protect the environment.'