How To Get Started

Installing a solar PV system is easy, just plug it in and it does the rest.

Designing and installing a hydro system is a bit more complex and initially requires a lot of data to decide if the site is going to be viable both from an economic and environmental perspective.

Many people who come to us start by asking "How much water do I need?”.

Hydro design always starts with "How much water have you got?”, and how much height is there between the point where you will take it out of the water course and the point where you will return it. This data together with the distance between the two points enables us to calculate what might be possible.

Very few water courses have the same amount of water in them all year round. Many might be full in Winter but are almost dry in Summer. as a result, many Pico hydro schemes only run for 4 - 6 months of the year, typically October to March. During this time they can make a very substantial contribution to the energy demand of a property when the load is highest as a result of short days and long cold nights. Many location additionally have solar panels as well as hydro to meet their electricity demand during summer months.

Environmental restrictions may specify that a certain volume of water cannot be removed from the water course and must be allowed to flow down the depleted reach (the distance between abstraction and return) to protect the existing habitat. This is typically referred to the "hands off flow"

When all this is known the turbine and its pipes and screens can be designed specifically for that location.

If you have a possible site then we can start with a free "desk top” Initial Viability Study which uses both the data you supply plus the various software and mapping systems we have to come up with a response which might be somewhere between "definitely interesting, or no chance”

This will enable you to decide if you wish to proceed further or drop the idea without spending any more time or money.

Please download our Initial Viability Questionnaire and fill it in as fully as possible before either scanning it and emailing it to us or sending it by surface post. We will use the information you have provided and the data we have to indicate if your proposal will be viable, or not.

You can download the Initial Viability Questionnaire HERE


  1. The grid reference for the abstraction and return points can be provided either as a 10 digit National Grid Reference comprising 2 letters and 10 numbers, or as Latitude and Longitude.

    You can use the web site Enter the nearest post code to bring up the satellite image and then zoom in if required. Right click on the point and a flag will appear. At the bottom of the page you will see both the grid reference and Lat Long displayed against the flag number.

    Alternatively you can use Google Earth to display the area. When you "hover” your mouse point over the satellite map you will see the Lat Long and altitude displayed at the bottom of the page.

  2. The most accurate way to measure the head is with a staff and level. For the Initial Viability Study it is generally sufficient to use the altitude data available from Google Earth. Alternatively you can estimate it using the contour lines on a 1:25k Ordinance Survey map.

  3. 3. The pipe length between the abstraction and return points can be calculated using the ruler / path tool in Google Earth or with a scale rule on an ordinance survey map. However, the measured distance is the true horizontal distance so will need to be adjusted to the slope distance using the height and a bit of trig. If you have lost your trig tables then go to where you enter 2 sides of a right angled triangle to calculate the length of the hypotenuse.

  4. 4. Measuring the average monthly flow over 12 months to generate an annual flow duration graph is usually the biggest challenge. On larger systems we can use a software package called LowFlows to provide a reasonably accurate 12 month forecast. However, on small systems this software may possibly be quite inaccurate so actual physical measurements to back up the computer predictions is always recommended. Deciding how to take the measurements is the first step and the various possibilities using a bucket, tennis ball and stop watch or a V notched weir are described in one of our info sheets.