Micro Hydro Power or Small Hydroelectric Power
Micro hydro power or small hydroelectric are terms given to installations that use the energy in falling water to produce electricity.
How does Micro Hydro Power Work?
Micro hydro power works by using falling water to drive a turbine, which generates electricity. This process converts potential energy stored in water held at height to kinetic energy which is used to turn the turbine and produce electricity. The amount of electricity a system generates depends on how efficiently it converts the power of the water into electrical power.
The amount of energy that a micro hydro power installation can generate depends on the flow rate of the water (i.e. how much water is flowing past each second) and the height, or head that the water is falling from, but useful energy can be produced from even a small stream. Micro hydro power schemes can be classified as low head, medium head or high head schemes, dependent on the height drop, and this is the main variable that is used to determine turbine type and system design. An example of a high head scheme would be a waterfall where the water intake can be close to the turbine but schemes can run over much larger distances such as the ‘run of the river’ micro hydro system depicted below which is a good example of a low head scheme where there is gradual drop in height over a large distance.
There are many different types of turbine available for a huge variety of micro hydro power applications, so view our information page for more details and to see which turbines are suitable for your micro hydro project.
How can Micro Hydro Power be used?
Micro hydro systems can be connected to the main electricity grid or as a part of a stand alone (off grid) power system. In a grid-connected system, any electricity generated but not used can be sold to electricity companies.
In an off-grid micro hydro system, electricity can be supplied directly to the devices powered, or through a battery bank and inverter set up. A back-up power system may be needed to compensate for seasonal variations in water flow.
How much energy does Micro Hydro cost and how much energy can it generate?
The amount of energy that a micro hydro power system can generate and the cost of its installation are very site specific due to the sensitivity to water head and flow.
As an idea, a typical small low head domestic system that could provide all the energy needs to an average property may cost around £20,000. For larger systems, the installation costs would generally be higher but excess energy could be sold to the National Grid for profit.
Generally, micro hydro systems are very reliable and maintenance costs are very small.
Is Micro Hydro suitable for me?
To tell if a hydro system is right for you, there are a few key questions to consider:
Is there a river or steam close to your home?
You'll need access to a fairly fast flowing water course, and the right to build around it.
Does the water flow vary significantly during the year?
If so, the hydro system may not be able to supply you with all the electricity you need during dry months. If you're not connected to the electricity grid, you'll need a backup power system.
Do you want to sell excess energy?
Hydro systems can be connected to the National Grid if a suitable connection point is available. Any electricity you generate but don't use can then be sold to electricity companies.
So, if you are lucky enough to have a river or stream close to your property and feel that micro hydro power is something that you would like to consider, Green Energy Consultancy can carry out an assessment to see if micro hydro power is right for you, just contact us and we can talk over your requirements or arrange a site visit if needed.
