How does Micro Hydro Power work?
In the drive towards generating power by natural sources such as wind and water, micro hydro turbines are becoming more popular. The supply of moving water, usually a stream, is essential but the power of converting the movement of the water to electricity is based on the same principle as that of wind turbines. The turbines are activated by the water and energy is produced when passed to a generator that produces electricity.
Ideally, the recipient of the power should be as close to the stream as possible although it is not essential but the greater the distance between the water source and the dwelling, the greater the cost will be. There are several different types of turbines on the market and the selection of the right one will depend upon the characteristics of the water source because the flow and volume of the moving water will determine which type of turbine is the most suitable.
Unlike wind or solar-based energy systems that are subject to almost total dependency upon the weather, hydro power is more reliable because the constant flow of water is only reduced in unusual drought conditions. This results in an efficiency rating of almost 90% which is far superior to those for wind and solar systems.
In assessing whether a micro hydro turbine system is feasible in a particular location, the web site of the Environment Agency should be visited. Flow and volume details are available for most streams and rivers in the UK and this information is essential in the initial feasibility study.
What types of Water Turbines are available?
There are three main types of water turbines: Impulse, Reaction and Submersible Propeller. The Impulse turbine would be used where there is a high head of water (about 6 metres) or where a stream runs down a steep slope. The Reaction turbine can operate where the head of water is as little as 1 metre but they need a large volume of moving water to operate successfully.
The Submersible Propeller type of wind turbine is the simplest but is also the least efficient. It is best installed in a fast moving stream or river. It could also be used on a moving boat or even a stationary one provided it is moored in moving water.
The installation of micro hydro turbine systems need consents from various bodies before work can commence. These include an Abstraction License from the Environment Agency plus Flood Defence consent. Planning permission will also be required from the local authority and permission will also be necessary from the electricity distribution network operator (DNO) to connect the system to the grid. It sounds formidable but there are firms who will undertake the chore of obtaining these permissions on behalf of potential users.
The Feed-in Tariffs (FiTs) scheme came into operation in the UK (except Northern Ireland) on 1 April 2010 which sets out details of payments available to householders providing electricity from low carbon sources.
There is such a wide variation in the sizes and types of micro hydro turbine schemes available it would be misleading to quote costs. Householders considering using this method of power generation should contact one of the many firms specialising in this field. See our handy Energy Assessment form for information on installers local to you.