Hydroelectricity

Hydroelectricity systems generate electricity from running water - usually a small stream. Small or "micro" hydroelectricity systems can produce enough electricity for lighting and electrical appliances in an average home.
Hydroelectricity systems are also called hydro power systems or just hydro systems.

• How do hydroelectricity systems work?
• The benefits of hydro systems
• Is a hydro system suitable for my home?
• Making the most of hydroelectricity
• Costs and savings
• Find out more

How do hydro power systems work?

Hydro power systems use running water to turn a small turbine which generates electricity. The faster the water flows and the more water there is, the more electricity can be generated.

The amount of electricity a system actually generates depends on how efficiently it converts the power of the moving water into electrical power.

Hydro power systems convert potential energy stored in water held at height to kinetic energy

The benefits of hydro systems

• Cut your carbon footprint: hydroelectricity is green, renewable energy and doesn't release any harmful carbon dioxide or other pollutants.
• Cut your electricity bills: hydroelectricity is free, so once you've paid for the initial installation you'll reduce or even eliminate your electricity bills.
• A lower cost option: installing a hydro system can be expensive, but in many cases it's less than the cost of getting a connection to the National Grid.
• Cheap heating and hot water: a hydro system may generate more electricity than you need for lighting your home and powering your electrical appliances - so you can use the excess to heat your home and your hot water too.

Is a hydro system suitable for my home?

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. Read more about selling your own energy

To find out if a hydro system is suitable for your home use our energy selector tool - coming soon.

Making the most of hydroelectricity

To make the electricity you produce go further:

• use low energy bulbs throughout your home - these produce the same amount of light as conventional bulbs and use up to 80% less electricity. Find out more about energy saving bulbs

• invest in energy efficient appliances. Find energy saving products
  

Costs and savings

Costs for installing a hydro system vary a lot, depending on the location and the amount of electricity it can generate. A typical 5kW scheme suitable for an average home might cost £20,000 - £25,000 including installation.

Savings depend on the amount of hydroelectricity that is used in place of electricity bought from another source. If the hydro system replaces electricity bought from the National Grid then typical savings could be substantial.

Maintenance costs vary but are usually low as hydro systems are very reliable.

From 1st April 2010 you could be eligible to receive cash for each unit of electricity you generate using this technology. Find out more about the Clean Energy Cashback Scheme

Planning Tip

The companion guide to Planning Policy Statement 22 on Renewable Energy recommends that if you are intending to install a small hydro system for example, that you make early contact with the developer, planning authorities, the Environment Agency and statutory consultees, such as Natural England to ensure that all statutory remits are met.

To help you with this process a tool – the Planning Performance Agreement (PPA) – has been developed. The PPA is a framework agreed between a local planning authority and a planning applicant for the management of complex development proposals within the planning process.

The benefit of the PPA is that it allows both the developer and the local planning authority to agree a project plan and programme, which ensures that the planning application is committed to a firm timetable, and one which is unconstrained by a 13-week target. It will also make clear, in advance, what will be required of each party.

Find out more

What's suitable for your home?
To find renewable technologies to suit your home, try the Energy Saving Trust home energy generation selector

Technologies
For more information on home energy generation technologies, contact your local Energy Saving Trust Advice Centre on 0800 512 012.

For specific technology questions, visit the British Hydro Association