Installing Domestic Micro Hydro Electricity Systems

Although obviously very site specific, hydro electricity is one of the cheapest and cleanest methods of producing renewable energy. The best location would be on a steep hill with fast flowing water. The great advantage over other renewable options is that the rate of power production is more or less constant and is not dependant on the weather or the time of day.

The initial installation costs are high but can be recovered through fuel bill savings and through the feed in tariff scheme, which pays you for each kWh of electricity generated.

How Much Does a Micro-Hydro System Cost?

Since installations are very site specific it is difficult to accurately estimate costs, however as a rough guide a 2kW system, installed by a professional, will be around £16,000. However, a 5kW system, despite being 2 and a half times as powerful, will cost only around 50% more, or approximately £25,000.

You will need to get a quote from a professional installer to get an accurate estimate of the installation cost.

Would a Micro Hydro System Be Suitable for my Home?

Obviously you will 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 (so a steeper hill means a bigger head).

Will I Need a Licence to Install a Micro Hydro System?

You will need an abstraction licence to remove more than 20,000 litres per day from a watercourse, even where is on your land and even though you will be putting the water straight back, therefore practically every project will require a licence.

A licence is obtained from the Environment Agency who will assess the impact on the ecology of the river and on flooding. It will take around 3 months to obtain. In addition planning permission may be required.

How to Find a Micro Hydro Installer

To benefit from the feed in tariff the system must be installed by an MCS registered installer. The official directory of Micro generation Certification Scheme (MCS) installer can be found at www.microgenerationcertification.org. A map of local installers can be found at www.saveandgenerate.com.

How Much Energy Will a Micro Hydro System Produce?

This depends on the particular 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. A typical UK household will use around 3,300kWh per year.

How Much Could I Earn From a Micro Hydro System?

In addition to what you will save on electricity bills, you can receive a payment of 19.9 pence for every kWh of energy produced plus an extra 3 pence per kWh for every kWh which is exported back to the National Grid rather that used in the home.

To put this in perspective, a 2kW system producing 7,000kWh a year, if 3,300kWh is used in the home, would return 19.9p x 3,300 + 22.9p x 3,700 = £1,504 per year.

It must be stressed of course that the actual amount a particular system could earn depends very much on the specific site. It should also be noted that the feed in tariff is due for review in 2011. Any projects registered prior to a review are however guaranteed to receive 19.9p (22.9p for exported electricity) per kWh for the next 20 years.