The Hydro Turbine

Inside the hydro turbine building on the Castle Drogo estate

Over the past year the Hydro Turbine, which sits on the River Teign has been restored so that it can once again utilise the power of the river.

The story of hydroelectric power at Castle Drogo began in 1916. At the same time as Castle Drogo was being built Julius Drewe wrote to Gilbert Gilkes and Co. (a well-established engineering company specialising in hydro-electricity generation) to enquire whether it was possible on the river Teign.

Work didn’t actually start until 1927, Sir Edwin Lutyens designed the building and Gilbert Gilkes and Co. installed 2 turbines. By March 1929 the turbines were producing electricity which supplied the castle. There were 332 electrical plug socks installed throughout the castle to power all of the gadgets in Julius Drewe’s thoroughly modern home.

The original switch board in the hydro turbine building.
The switch board in the hydro turbine building at Castle Drogo.

The supply wasn’t always reliable as one family member recalls, “when it was windy the power was unreliable and mother was never able to have a washing machine.”

As part of the National Trust’s objective to produce 50% of its energy from renewable sources by 2020 and using a building for its original purpose, for the past year work has been undertaken to reinstate the hydro turbine.

" We’re absolutely delighted that after all this time, we can finally fully reinstate the entire character of this remarkable place, with its renewable energy system powering the property once again. It’s is fantastic to be able to share with the public for the first time what must have been absolutely unique in its day – and the message of generating sustainable , renewable energy is something that resonates with all of us even today, in an age where talking climate change is an increasingly urgent issue."
- Graham Waddell

The majority of the original infrastructure was found to be sound and reusable. The 2 Francis turbines were sensitively restored and the concrete pipe which takes the water from the weir to the turbine house was still in good condition.

As well as restoration, the project has also required the installation of new elements, including a state of the art intake screening system, which will ensure that fish and eels cannot enter the turbine system. A new cable has also been installed to bring the power directly to the visitor centre.

The turbine house will be commissioned in late October 2017 and will start generating electricity once there is sufficient water flow in the river meaning that generation will slow in the summer months and increase through the autumn and winter, whilst ensuring the river retains sufficient natural flow.

The electricity will be used by the visitor centre and any excess will be used to heat one of the boilers in the biomass house so there will be no waste.