Staverton Leat



What: Archimedes Screw on the Dart
Where: Staverton
Why we loved it: An exciting project with encouraging estimated returns, that built on our working relationship with Hydrosense.
Total Installed Capacity: Est. 100 kW
Average Annual Generation: Est. 360,000 kWh
CO2 equivalent per year: 162 tonnes
Customer equivalent per year:  109 families typical use
Est. annual Income to TRESOC: (2% share): £6,000
Total Project Cost: Est. £916,000


Staverton Hydro Community Benefit Society to be dissolved

Between 2014 and 2020 we were co-developing a small-scale 100 kW hydro power plant at Staverton leat in joint venture with Hydrosense, developers of the scheme at Totnes Weir. To do this we set up a separate, project-specific ‘BenCom’: Staverton Hydro Community Benefit Society. Agreements were in place with the Staverton family who own the land where the leat is located and with Dartington Hall Trust, who would have received the electricity generated.

As of 2021, the Staverton Hydro Community Benefit Society is to be dissolved. With generous support from the Rural Community Energy Fund, SHCBS was able to carry out a feasibility study and to prepare and submit a full planning application to the local planning authority for a single hydro turbine on the leat at Town Mills, Staverton. Expert discussion on the Habitat Risk Assessment with the Environment Agency and Natural England in 2019 focused on the conservation status of salmon in the Dart. The conclusion of the EA was that they could only permit abstraction of water during a three month period from January to March to avoid the possibility of damage to migratory salmon and sea trout. This would mean that the financial return from electricity generated could not repay investment in the scheme. Following this decision the TRESOC Board has decided to dissolve the Society and is now in the process of doing so. However, we are grateful to everyone who supported this project for so long and hope it may yet be realised at a later date.

We had confidence in this project because there is an historical precedent—the plant once generated electricity for the Dartington estate in the 1930s (see the story below).  Also, the local developer, Hydrosense, has a successful track record of similar hydro projects which satisfy many stakeholders (Environment Agency, planners, anglers, neighbours and others), and we know the river flow in the Dart offers an excellent opportunity for generation from the work done for the Totnes Weir hydro scheme, and from the data from the very first Archimedes screw turbine in the UK at River Dart Country Park. Co-development of the project also offered a much higher projected rate of return.

In addition to generating electricity from a single Archimedes turbine, the project would have regenerated the leat, which has fallen into disrepair, with a new fish pass and smoult pass to help up- and down-stream migration of river life.

Back in June 2014, TRESOC met with Hydrosense, the landowners, Parish Council members, local residents, representatives from the Environment Agency and the Dart Anglers Association to progress the Staverton Leat hydro project. The meeting was very positive, with all present in favour of the scheme. During the meeting, Julian Sharpe of the Dart Anglers Association said, “I am very, very keen to see this scheme happen, and my beloved fish protected.” A member of the Staverton Leat Working Group said, “This is the best answer to our problems”.

Staverton Hydro Community Benefit Society (SHCBS) was set up by TRESOC specifically to develop the Staverton Hydro project. In June, 2017 a £20,000 grant from the Rural Community Energy Fund (RCEF) was awarded to kick start the development of the 100kW hydro power plant at Staverton Leat. SHCBS used the grant to do a feasibility study and part was also used for outreach work to engage the local community. This included a series of August, 2017 Walk & Talks to visit the project site and, the ‘REEL‘ programme piloting at St. Christopher’s School, Staverton.

You can read a press release, as Planning Application was submitted [October, 2018], and the Rural Community Energy Fund’s Feasibility Report [January 2018).

Staverton Leat  |  The History

In June 1930, Dorothy and Leonard Elmhirsts’ daughter Ruth, aged four, flipped a switch and formally started up a new hydro station to bring hydro-electric power up to the Dartington Estate — a J. J. Armfield water turbine installed within Town Mills, near Nappers Crossing at Staverton leat. Town Mills, which was leased from the Church Commissioners by Dartington’s trustees, was previously a corn mill built over Staverton leat.

In those days, electricity to this area was controlled by Torquay Borough Corporation. They had advised the Elmhirsts when they bought the estate in 1925, that the Hall and village were too remote to have a mains supply. With his appreciation of small scale electricity generation, Leonard Elmhirst moved forward with plans to convert Town Mills, into an ‘automatic turbo electricity generator’.

From 1932 to 1942, the plant provided electricity to Staverton Builders, but wartime production proved too demanding. Staverton switched to the mains and the trustees were ready to scrap the plant. However, the estate’s electrician, Frank Christy, was able to make the modifications necessary to overcome the technical obstacles. He also successfully conducted the high diplomacy needed to enable the plant to be run in connection with the Torquay supply.

The plant produced power for forty years via its two turbines (15kW and 35kW). Dartington took the electricity it needed and more if necessary, although by the late 60s the plant was primarily serving the Hall area. In the early 70s, the plant was closed down. Town Mills was bought at auction by Nigel Amherst, a member of staff in the music department at Dartington College of Arts and it remains the private residence of the Amherst family.

(Thanks to the staff of The Totnes Archive, part of Totnes Museum for this information)

Read our two further oral history case-studies, where Tresoc Intern Lawrie speaks to two local families about their Staverton memories and the history of the original leat and turbines.


Totnes Weir



What: An equity stake in a twin Archimedes Screw Hydro System and new fish pass
Where: at Totnes Weir, developed by Hydrosense.
Why we love it: Fantastic landmark scheme with widespread support. Local water supply pumped using energy from the river. Win-win for clean energy and spawning salmon & sea trout. Great partnership arrangement with developer and community.
Total installed capacity: 300 kWp
Average annual generation: 1,250,000 kWh
CO2 equivalent per year: 597.5 tonnes
Customer equivalent per year: 333 families typical use * Estimate based on the most recent statistics from the DECC showing that annual UK average domestic household consumption is 4,115 kWh.
Est. annual income to TRESOC: (21% stake): £37,500
Total cost: £500,000 to buy a 21% stake in the project.



The Totnes Weir Hydro power plant was constructed in 2015 and began generating electricity in December 2015. It has been performing ahead of expectations with electricity generated being higher than forecast.

Designed to withstand at least a one in 100 year flood and the additional impact of high spring tides and increased river levels due to climate change, the scheme has coped admirably with recent storms.

Two Archimedes Screw turbines are generating clean, renewable electricity for Totnes.  The scheme is expected to generate around 1,250 MWh of clean electricity each year – enough to power around 300 homes for at least 40 years*.

A new best practice fish pass has been installed adjacent to the turbines to allow more salmon and sea trout to migrate past the weir and spawn in the Dart catchment.  An automatic fish counter has also beed installed to monitor the number and sizes of fish using the pass.  Extensive research has proven that fish can pass through the slowly rotating turbine with no adverse effects.

A recreational area is being created near the turbine house with information about the scheme and a new canoe launch platform has been created.

Tresoc now participates the Annual Archimedes Screw Festival at the Totnes Hydro Weir, organised by The BioRegional Learning Centre.

* Estimate based on the most recent statistics from the DECC showing that annual UK average domestic household consumption is 4,115 kWh.



Sowton Weir



What: An equity stake in an operating single Archimedes Screw
Where: on the River Teign near Chudleigh, designed and built by Hydrosense.
Why we love it: Already generating electricity and ready for investment. Increases in migratory fish population in the upper Teign as a result of new fish pass installed with the project.
Total installed capacity: 100 kW Average annual generation: 368,000 kWh CO2 equivalent per year: 165 tonnes
Customer equivalent per year: 112 families’ typical use
Est. annual income to TRESOC (30% stake): £13,800
Total Cost: £200,000 to buy a 30% stake in the project
Status: Commissioned in October 2013


Sowton Weir

We have signed an agreement to invest £200,000 in the recently constructed 100 kW hydro power plant at Sowton Weir on the River Teign. Like the Hatchlands Farm solar roof, income will begin to accrue as soon as the purchase is made, with an internal rate of return to TRESOC of around 7% per annum. As with our estimates for Totnes Weir we have calculated returns over a 30 year-period rather than the full period of the lease to exercise some caution in our estimates. Effective optimization at the site has led to better than expected returns from the project. The generation meter readings have been matched to flow data to show that the system is producing slightly more electricity than predicted. Although exact numbers are hard to predict, there may be an increase in fish populations of 10 to 30% over the next 3 to 5 years.

The Archimedes at Sowton Mill has improved the fisheries ecology of the River Teign by allowing more juvenile salmon and sea trout to reach the sea. The improved fish pass at the weir means more adult salmon and sea trout can reach spawning grounds on the upper Teign. An automatic fish counter has been installed that records fish numbers and species using the fish pass. This is one of only 4 fish counters in the South West and provides valuable information for the Environment Agency and the Teign Fishing Association.”

Pete Kibel, Fishtek Consulting Ltd.