Hydro electricity takes advantage of the energy that exits within the water and turns that energy into electricity.
So, how do micro hydropower systems work?
The aforementioned energy is captured from running water in a river or stream that falls from a height to a lower level, i.e. a waterfall. The captured energy is then used to generate electricity as the power of the water is converted into kinetic energy which is used to turn a turbine which in turn produces the electricity. The higher and faster the water falls, the more electricity is generated.
How much electricity will a micro system produce?
The energy output will vary depending on the characteristics of each individual site but, as an example, a 2kW system with a 3m head and a flow rate of 500 litres per second could produce around 7,000kWh per year. To put this in perspective, a typical UK household will use around 3,300kWh per year; this then allows you to sell your excess electricity back to the grid through the government's Feed-in-Tariff.
Would a hydro system be suitable for my home?
Obviously you need to have a river or stream flowing through your land and the flow will need to be sufficiently powerful. There are a number of variables to consider and you will need to have the site assessed by a professional but the two basic factors are flow and head. Flow is the speed of the water flow and head is the distance the water falls to reach the turbine.
How Much Does a Hydro System Cost?
Since installations are very site specific it is difficult to accurately estimate costs - however, as a rough guide a 2kW system will be around £16,000. Costs are not necessarily directly proportional to the power of system you install, since a 5kW system can cost between £20,000 to £25,000.
Please note that these costs are speculative.
Will I need a planning permission to install a Hydro System?
Planning permission usually takes the form of an abstraction licence, obtained from the Environmental Agency.
The benefits of micro hydro systems
• Micro hydro systems generate electricity 24 hours a day, potentially generating all the electrical requirements for your home.
• Excess electricity can be exported to the national grid, providing an income through the government's Feed-in-Tariff.
• Although obviously very site specific, hydroelectricity is one of the cheapest and cleanest methods of producing renewable energy.
• Installing a hydro system can be expensive, but in many cases when the site is off grid, it can often be a cheaper alternative to connecting to the national grid.
• Hydroelectricity is a 'green', renewable energy and doesn't release any harmful carbon dioxide or other pollutants.