Eco Evolution Blog

Ardtornish Estate is a Highland estate in Scotland located in Morvern, Lochaber.  The present owner of the estate is passionate about conservation; and with the estate team has spent the last few years creating a hydro-power systems high in the hills to provide low-carbon, renewable energy.

With conservation and sustainability at the heart of the estate’s objectives, three hydro power schemes are currently in place, another is under construction, and a fifth , an Archimedean Screw hydropower turbine is due to be commissioned in July 2016. A biomass woodchip boiler heats the mansion house, and green initiatives are being developed to reduce further the estate’s carbon footprint.

The delivery of the Archimedean Screw hydropower turbine required delivery along some single track roads through stunning mountain scenery. This installation will provide a unique visitor attraction as well as supplying power to the estate businesses and holiday cottages.

Rated at 100kW this semi compact Archimedes Screw hydropower turbine at Ardtronish Estate will save 86 tonnes of CO2 annually. Mann Power Consulting Ltd., the UK based Archimedean Screw specialists designed the equipment for this project.  After various consultations it was decided that the most suitable turbine for the site was a semi compact Archimedes Screw Hydro turbine which was manufactured by Landustrie based in Holland.

The Archimedes Screw hydropower turbine is a new application of an ancient technology. For thousands of years the screw was used to pump water up from rivers or streams to irrigate farm land. Now, using the same system in reverse the Archimedean Screw is being used to harness the power of the water to generate hydroelectricity. Once your turbine has been commissioned and connected to the grid you’ll be generating hydro-electric power 24 hours a day, seven days a week. Whether the power is for your own property, to sell back to the grid or a combination of both, the Archimedean Screw will likely pay for itself several times over in the course of its operational lifetime (depending on the feed-in tariffs available) . And what’s more these turbines can be scaled to suit all needs – from small domestic applications to huge industrial installations.

The basic requirements required for an Archimedes Screw hydro turbine are:

• A water source with a drop of at least 1.5 metres
• Access rights to that water source
• A grid hook-up point less than 500 metres from the water source – unless the Screw is being used for ‘off grid’ generation only.

If your site satisfies these criteria then there’s every chance you will be able to harness the power of the waterway to generate hydroelectricity. And Eco Evolution will be delighted to pilot your scheme all the way through to delivery.

If you’re still not sure whether your site is right for an Archimedean Screw turbine, get in touch and we will be happy to discuss the specifications and requirements in greater depth.

Ludford Mill hydropower scheme is a community investment project which will supply hydropower for local households with excess power supplied to the grid. The Ludlow Hydro Co-operative made the decision to harness the river Teme for Ludlow by bringing the 17th Century listed Ludford Mill back to life by installing  a state-of-the art Archimedean Screw hydropower turbine, cunningly designed to fit in with the current buildings. Installed at a 17th Century listed mill and horseshoe weir on the Teme the semi compact Archimedean Screw hydropower turbine with a maximun power output of 29kW and an estimated annual output of 170,000kWh will save 73 tonnes of CO2 annually.

Artists impression of Ludford Mill hydropower scheme

The Archimedean Screw is contained inside an enclosure which is built to complement the structure of the existing buildings, and the screw itself will not be visible. The enclosure will also provide sound insulation so that noise levels will be kept very low.

The scheme was designed by Mannpower Consulting Ltd and the civil engineering work began on the hydro turbine in the second week in August 2015 and the schedule was that by the second week in October the main enclosure walls would be complete, with stop logs top and bottom, which would allow the removal of the temporary cofferdam and retreat out of the river itself.

Over the next few months between October and January preparations were put in place to build the pump house for the electrical control gear, sluice gates, screens and walkways were installed and electrical cables and hydraulic lines were in place for the arrival of the turbine.

Then 30kW Archimedean Screw hydropower turbine designed by Landustrie arrived on site in March and was commissioned by Mannpower and Eco Evolution in April.

Once again we see the Ancient power of Archimedes being used for hydropower generation because if it’s fish-friendly credentials. The Archimedean Screw turbine provides a fish-friendly alternative to conventional turbines, ideally suited to low-head (1m-10m) sites, and sites with fish protection issues. Extensive fish passage tests have conclusively demonstrated that the large water chambers and slow rotation of the Archimedean Screw allow fish of all sizes, and debris, safe passage through the turbine. As a result, the Environment Agency has agreed that no screening is required.

If you are the owner of an old mill site or a potential hydro site or are a community group interested in developing a hydro project for community use please contact us here.

The Hydro scheme is located in Donside Village in Tillydrone, on the banks of the River Don. The Village is a relatively new, sustainable community based on the site of an old papermill. The hydro scheme will use the existing mill lade with the addition of a 100kW Archimedes screw. Donside Community Hydro plan to raise the money to build the scheme via a community share offer. Aberdeen Community Energy says Donside Hydro will generate £30,000 every year for community initiatives.

Photo Credit: Highland Eco-Design

The scheme which is at design stage will generate enough electricity to power 122 households.

System Elements

Available head 1.75m
Max. flow rate 10,000 l/s
Screw bladed length 5.61m
100kW Archimedes Screw
Screw weight 20 tonnes

The proposed Donside hydropower scheme

Community Benefits

Aberdeen Community Energy (Ace), a community benefit society set up by members of the Donside Community Association (DCA), will be launching a community share offer over the next few weeks to back the Donside Hydropower scheme.

The proposed hydropoweer scheme will draw water from the River Don to create renewable electricity that will be sold to the national grid. Surplus profits from the initiative will be channelled into a community fund that will be used to achieve social and environmental benefits for local, deprived communities. Ace together with their partners at the DCA have been working towards launching the scheme for the past three years and are finally in a position where they can share the project with the world, and open it up to investment.
The Donside Hydropower scheme will help Scotland on its journey towards 100% renewable electricity by 2020, and it will also create a sustainable community that truly works for its inhabitants and riverside setting. Aberdeen Community Energy are already working closely with members of the Donside and Tillydrone areas to identify priorities for the community fund, with their immediate focus being on improving the riverside for public use. They are also looking at the longer term outcomes, and have set up a social enterprise called Sinergy that will route surplus income into projects that will deliver sustainable benefits for the wider area.

With construction planned for late May 2016, Ace said potential investors in the scheme could expect an “ethical, low-risk investment opportunity” delivering around a 5% return on their investment. Ace, which has so far raised around £150,000 from loans, grants and investment from Ace directors, is also seeking conversations with businesses or individuals who may be interested in supporting the initiative financially in the short term, as either a lender or investor.
The community share offer will be available for investment from April 2016. A launch event will take place at an Aberdeen city centre location in the weeks after the share offer is live.

The Brahan estate Archimedes Screw hydropower project, an ultra low head scheme operating on only 1.5m head and producing 100kW from twin screws was commissioned near Inverness ahead of schedule and is now delivering power to the local farm with excess being sold back to the National Grid. The river level upstream varies throughout the day by up to 700mm because of sudden water releases from a large hydropower station upstream, requiring a unique design with each screw set at a different height to optimise generation.

Rated at 100kW this semi compact Archimedes Screw hydro turbine at Brahan Estate will save 258 tonnes of CO2 annually.

The Archimedes Screw hydropower turbine is a new application of an ancient technology. For thousands of years the screw was used to pump water up from rivers or streams to irrigate farm land. Now, using the same system in reverse the Archimedean Screw is being used to harness the power of the water to generate hydroelectricity. Once your turbine has been commissioned and connected to the grid you’ll be generating hydro-electric power 24 hours a day, seven days a week. Whether the power is for your own property, to sell back to the grid or a combination of both, the Archimedean Screw will likely pay for itself several times over in the course of its operational lifetime (depending on the feed-in tariffs available) . And what’s more these turbines can be scaled to suit all needs – from small domestic applications to huge industrial installations.

Mann Power Consulting Ltd., the UK based Archimedean Screw specialists designed the equipment for the Brahan Estate project.  After various consultations it was decided that the most suitable turbine for the site was a semi compact Archimedes Screw Hydro turbine which was manufactured by Landustrie based in Holland.

The hydropower scheme also required two fish passes operating at different levels, and an automatic bypass sluice gate to maintain ecological flows at all times.

Archimedean Screw turbines offer a hydropower solution that is:

• Commercially attractive & cost effective
• Practical & efficient
• Fish-friendly
• Easy implementation in existing situations (no civil constuction work)
• Insensitive to clogging
• Low maintenance costs
• Improvement of water quality
• Self regulating to changing water flow
• Long life time
• Scaleable & bespoke

The basic requirements required for an Archimedes Screw hydro turbine are:

• A water source with a drop of at least 1.5 metres
• Access rights to that water source
• A grid hook-up point less than 500 metres from the water source – unless the Screw is being used for ‘off grid’ generation only.

If your site satisfies these criteria then there’s every chance you will be able to harness the power of the waterway to generate hydroelectricity. And Eco Evolution will be delighted to pilot your scheme all the way through to delivery.

If you’re still not sure whether your site is right for an Archimedean Screw turbine, get in touchand we will be happy to discuss the specifications and requirements in greater depth.

The Totnes Weir hydropower scheme was developed by Dart Renewables and when completed it is estimated that the two Archimedean Screw hydropower turbines rated at 150kW each will generate 1,200 MWh of renewable energy every year, enough to power the equivalent of around 400 homes and saving 500 tonnes of C02. It is expected that around two thirds of the electricity generated will be used to power King Edward VI Community College, which serves around 1,700 students, and Atmos Totnes, a community development involving the construction of 60 to 70 social housing units and housing for older people.

The environment

Numbers of migratory salmon and sea trout are in decline in the river Dart, in part due to difficulty in passing the Totnes weir. The species are currently being held at the weir, where seals predate, leading to mortality of the fish. The construction of the Totnes Weir scheme will include the installation of a modern fish pass which allows the fish to pass the weir and continue their journey upstream to spawn. It is expected that this will reduce salmon and sea trout losses in the river Dart and over time increase the population of these species in the river Dart catchment. The scheme would also encompass an additional Larinier type fish pass, alongside the repair of the existing pool-and-traverse fish pass. Underwater cameras and a fish counter will estimate Salmon and Trout migration to spawning grounds in the Upper Dart. This will provide valuable data on the species in the river Dart which will be shared with both the Dart Angling Association and the Environment Agency.

Community benefits

Dart Renewables developed the Totnes Weir scheme in close conjunction with the local community in Totnes and the scheme will benefit the community in a variety of ways. Around two thirds of the power generated by the Totnes weir scheme will be used to power the local school in Totnes, King Edward VI Community College (KEVICC), and a community development of affordable homes and community facilities for the Totnes area which is being managed by the Totnes Community Development Society (TCDS). Electricity will be sold to these organisations at a mutually beneficial rate compared to prevailing market rate.

The Environment Agency, the Dart Angling Association, the TCDS and TRESOC (the Totnes Community Energy Society) have been closely involved in the consultation process for the Totnes Weir scheme and are very supportive of the project. A small classroom complex is proposed for the site next to the weir to be used by a KEVICC educational trust.

Larinier fish pass

Fishtek were responsible for the design of the new Larinier fish pass and the improvements and modifications to the existing fish pass on the far side of the river from the hydropower scheme. A few images of the turbines and fish pass are shown below.

The fish pass can be seen in the images above (running at a very high level as the turbines were temporarily turned off when these images were taken). A fish counter is to be added at the upstream end of the fish pass very shortly and this will provide invaluable data for the ongoing monitoring of fish populations in the river.

Funding

Triodos Bank helped Dart Renewables raise the £1.3 million needed to build the hydro power scheme through a Bond Issue. Local investors were offered the opportunity to invest a minimum of £2,000, with the minimum for those living further than 15 miles from Totnes being £10,000.  Investors could earn up to 8% return a year for up to 8 years.

Once again we see the Ancient power of Archimedes being used for hydropower generation because if it’s fish-friendly credentials. The Archimedean Screw turbine provides a fish-friendly alternative to conventional turbines, ideally suited to low-head (1m-10m) sites, and sites with fish protection issues. Extensive fish passage tests have conclusively demonstrated that the large water chambers and slow rotation of the Archimedean Screw allow fish of all sizes, and debris, safe passage through the turbine. As a result, the Environment Agency has agreed that no screening is required.

If you are the owner of an old mill site or a potential hydro site or are a community group interested in developing a hydro project for community use please contact us here.