Small Scale Hydro Electricity.

Water from your stream or river is run through a penstock (pipe) to a turbine installed in a powerhouse. The turbine is rotated by the water, driving a shaft in an electrical generator.  The water is returned to the stream or river.

‘Is my stream/river suitable?

We will conduct a feasibility study and if it looks suitable hydrometric measurements and a report will be undertaken.

A water course that runs down steeply (high head) but has a low flow can be particularly viable for a micro hydroelectric scheme.

‘How much power can I generate?’

This obviously depends on many variables. For example a stream that has an intake at 50 metres above the powerhouse and a flow rate of 40 l/s can generate  around 14 kWs of power at maximum capacity.

‘What is the Feed-in-Tariff?’

FiT is a government incentive to use and produce renewable energy. If eligible you can receive payment for producing energy for yourself, and additionally for providing electricity fed (your surplus) back to the grid. You will save money on your energy bills by using what you produce on site.  To be eligible for FIT payments you must have all the correct paperwork in place. 

‘What licenses do I need for a hydro power system?’

Each site should have an Abstraction and Impoundment License, Flood Defence Consent, Full Planning Permission, and a Grid Connection Agreement. 

‘How much will it cost me to build a hydro scheme and what am I paying for?’

The costs involved vary depending on the size of the scheme. For example if the powerhouse and the intake are far apart then the cost will be higher due to the increased amount of materials required. The cost will depend on the level of consultancy required, size of your scheme, and grid connection requirements. 

Current projects have ranged from £100,000 To £350,000 for systems up to 100kWs.  However it is common for projects to cost more than this.

A good hydro site should pay for itself in between 5-10 years depending on the amount of rainfall per annum and the level of work required.

‘How long will it take?’

The average time is 2-3 years. The majority of that is taken up with licencing and permission which is a detailed procedure.

‘What is the environmental impact?’

This varies depending on site location as each hydro project is unique.  Snowdonia Hydro takes steps to ensure we have a minimal environmental impact and aims to leave a site in better ecological condition than when we started work. 

As part of the technical design we conduct tree, ecology, geomorphology and if necessary an archaeological survey to assess the potential impact. The intake and powerhouse sites will be accessed frequently during building work. We use specialised companies for steep access work and we aim to regenerate the area after work has been completed.

The aim is to produce electricity from a renewable source overall reducing the environmental impact of electricity production.

‘What happens once a hydro site is up and running?’

Snowdonia Hydro offers twice yearly maintenance checks on the system, but generally they are maintenance free.  The intake screens will need to be checked for any blockages especially during autumn and the powerhouse should be visited frequently to check for any errors with the controller.  This is more important during the first year when there might be a “settling” period.

‘What role does Snowdonia Hydro play in your hydro project?’

Snowdonia Hydro act as principal consultant throughout your scheme to ensure all the right information gets through to all the right people.  We also offer project management and access to all the right trusted tradespeople at the right time.  We specify and order the equipment for your project and oversee the commissioning and sign off of your project.

‘Is there grant funding available?’

No not for private schemes.  There is funding for community projects but if you are in receipt of EU funding, it usually means you will not be eligible for FIT payments.

‘What type of hydro turbine is suitable for my site?’

Snowdonia Hydro will specify a suitable turbine during the technical design phase. 


If you need more support and your enquiry isn’t answered in the FAQs, please get in touch with us and we will get back to you as soon as possible.

A percentage of the water is taken from the river or stream, through a carefully designed weir.

Water is diverted from the watercourse to the powerhouse either over, or undergound through the penstock; large bore piping.

The head is the distance that a given water source has to fall before the point where power is generated.  In short, for a given water flow, a larger head will be converted into greater energy.

The pressurised water is excites a turbine which drives the alternator. The power is then synchronised to the grid via a computerised control box.

The powerhouse is connected to the national grid, unless the system is to be used off grid.

Once the energy has been harvested from the water, it is returned to the watercourse.

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