Small-Scale Hydro In Our Community

Introduction

60 years ago, aside from diesel generators, most of our regions electricity came from hydro electric installations. Most of the communities in our region probably have the remnants of these systems under their noses in the form of decommissioned reservoirs, old mills and run-of-the-river schemes. However, with the advent of the National Grid came the decommissioning and abandonment of many of these schemes. Over the last five years there has been a huge upsurge of interest in hydroelectrics, as a means of generating income for farmers, as historical restoration projects and as a way for community groups to kick-start their energy initiatives. In 2008 there were six hydro installations installed in The Green Valleys (we even have two neighbours with their own hydros!) and we are keen to develop local capacity for survey work, employment for installers, setting up new community initiatives and realising the huge potential that exists.

Due to their very nature, and the fact that much of our region's waterways are Special Areas of Conservation (SACs), it will always be imperative that all new schemes do not have a detrimental impact on the environment. With the assistance of agencies such as the Environment Agency (EA), the Countryside Council for Wales (CCW), the Brecon Beacons National Park Authority, amongst others, we are keen to develop new models and initiatives that can ensure that all new schemes are of benefit to the local environment through the creation of new habitats, reducing flooding issues and protecting the outstanding natural beauty of our region.

How Does It Work?

Micro hydro, or small-scale hydro, is one of the most environmentally benign energy conversion options available, because unlike large-scale hydro power, it does not attempt to interfere significantly with river flows. Hydropower is a well-proven technology, relying on a non-polluting, renewable and indigenous resource, which can integrate easily with irrigation and water supply projects.

Hydro power works by using falling water to drive a turbine, which generates electricity. The amount of energy produced by a hydro power scheme depends on how far the water is falling (called head) and the flow rate (i.e. how much water is flowing past each second). Low-head sites are generally considered to be where the head is less than 3 metres. High-head sites, especially in the Brecon Beacons, can have up to several hundred metres of head.

High Head Systems usually have a water intake above a weir or dam. Some of the water flowing along a watercourse is re-directed into the intake which screens for debris and fish to prevent them entering the turbine. From the intake the water then leads into a channel or pipe (called the penstock) where it falls down through one or more turbines. The water passing through the turbines generates electricity and is returned to the river afterwards.

Low Head Systems: One way to identify sites for small hydro power projects is to look for old water mill sites (or place names including the word “mill”). Usually the highest cost in Hydro power development is the building work needed to house the turbine appropriately and redirect water from the river through the turbine, and old mill sites may have some of the building work in place already. Although it is possible to use existing waterwheels to generate electricity it can be expensive and inefficient due to the gearing required to get the low revolutions per minute (rpm) of the waterwheel to the much higher rpm required by the electricity generator.

What Permissions Do I Require?

Environmental criteria are very important in deciding whether a site is suitable for hydro power. The following permissions are usually needed to run a hydro power project:

· Access permission to use the land

· Planning Permission from the National Park Authority

· Abstraction and Impoundment licenses from the Environment Agency

The environmental impacts associated with construction and possible alterations to the river environment should be minimal for a micro hydro power project if the scheme is well designed. Nevertheless, sites should still be chosen carefully.

You will almost certainly require an abstraction and containment license for any hydro scheme. These licences are granted by the Environment Agency (EA). The EA recognises the potential benefits of small-scale hydropower to rural communities and in meeting local needs for power, but by their nature, hydropower proposals often require the EA to balance the requirements of developers with protection of the environment. Where a proposed scheme is inappropriate for its location the EA will advise a prospective developer at as early a stage as possible. It will take a positive view of reasonable and well designed proposals for hydropower schemes and will work with developers and others in attempting to agree a viable, sustainable project.

We advise that you follow three separate enquiries for your hydro system. First, ensure that you have a legal right to use the land. If you do not own the land ensure that you have written consent from a landowner and that your consent has been checked by a legal professional. Secondly you will require planning permission for your development. We advise that you consult with an accredited installer and develop detailed designs of the project before seeking planning permission. The National Park Authority Planning Department view hydro installations favourably, but they will require detailed drawings of your proposal. Thirdly, you will be required to contact the EA for your licenses to use the water. We recommend that you contact them first of all to ensure that they have no major concerns with your particular watercourse, but you will be required to have access and planning permissions already granted for the EA licences to be approved.

Costs and Maintenance: High head hydro systems have proved to be very reliable and can have a design life of 25 years or more. Costs vary due to a range of factors such as length of penstock, size of turbine and geographic location. Hydro systems generally require very little maintenance other than ensuring they are kept relatively clean and checking that the amount of flow in the watercourse is not at a low level (thus affecting your license to use the water).

Do I Need Planning Permission?

Click here to download our Small Scale Hydro (High Head) Planning Information Sheet

Click here to download our Small Scale Hydro (Low Head) Planning Information Sheet

Examples Of Micro-Hydro In The Green Valleys Region

Within The Green Valleys region there are presently 10 hydro electric installations ranging from a couple of kilowatts to 36kW. You can learn about several of the individual schemes here.

Surveying In The Region

Throughout early 2009 the community groups in The Green Valleys region identified 92 possible hydro schemes in the Green Valleys. All of these have now been surveyed by trained hydro installers and the feasibility studies are coming in. The first 23 sites that were surveyed came back as having the potential to generate 399kW (which represents 6% of the annual electricity demand for the homes in the Brecon Beacons).

Talybont-on-Usk Community Hydro Scheme

A 36kW Cross-Flow Turbine utilising the compensation flow from the Talybont Reservoir. Completed in 2006 the hydro installation now generates over £20,000 per year for the local community. For further information visit their website.

Dyffryn Crawnon Hydro

In 2007 Pip and Gill applied for assistance from the Brecon Beacons National Park Authority’s Renewable Energy Assistance Program (REAP) and were awarded £2,067 towards the cost of the installation of a hydro generator with a 3.3kW potential. The generator is powered by a small spring that originates high up on the hillside.

Pip decided on a renewable resource in an effort to reduce their impact on their environment and to use the resources available to them in a sustainable way. They decided on a hydro installation due to the availability of resources and the consistency of supply. Pip and Gil consider it a benefit to not be reliant on the larger power companies for supply and to be able to maximize the sensitive use of the resources available to them. They were surprised by the bureaucracy of some of the grants available to them and agree that a step by step guide to all the elements of the installation process would have been helpful.

Abercraf Hydros

Howell and Llinos Williams applied to the Brecon Beacons National Park Authority’s Renewable Energy Assistance Program (REAP) fund for funding and was granted £2565 towards the cost of installing the Hydro electric system. This system was not eligible for any of the UK government grant schemes. He runs a system with a 11kW potential. This generates approximately 90,000 kwh per annum.

The Williams’ household decided on a renewable source of energy supply in 2008 as a reaction to the rise in oil prices. They originally considered a wind turbine but a neighbor had installed a hydro system and this, combined with the abundance of water available, sealed the decision.

The Williams’ consider the security of energy supply, the diversification of their farm business and the financial return from selling their excess electricity back to the National Grid as being the greatest benefits of the installation. They expect to pay back their investment within three years based on the trend of the last two years precipitation.

Howell experienced no unforeseen problems during the installation of the hydro system, which is housed in a small shed next to his house. The process of obtaining planning permission took some time but everything went smoothly and they recommend similar installations to all those with the available resources.

Llanover Hydro

Farmer Alan Williams began his journey thinking about a wind turbine system to assist in his diversification plans for his business. He later discovered that he had an ideal site for a small scale Hydro electric system and by 2007 his 10kW system was operational. He now generated 80,000kWh per annum and sells the majority of the electricity he produces directly to the National Grid.

The project took eight months to complete, with members of the Williams family helping out with the construction work. Now that it is finished the hydro turbine will generate approximately 50 megawatt hours a year, which is enough to supply 20 homes. The farm now enjoys a renewable source, which runs 24 hours a day seven days a week. After leaving the turbine the water is then returned to the same stream with no impact on the environment. Alan’s neighbour is now planning a hydro on his land as well.