SW hydropower resource assessment

The Environment Agency has undertaken an assessment of the potential hydropower resource in the south west as part of a wider assessment of England and Wales.

The assessment estimates and maps the available unconstrained resource potential for hydropower generation in the south west using basic environmental sensitivity constraints associated with exploiting them, principally:

• the probability of migratory fish species in river systems
• Special Areas of Conservation (SAC)

The resource potential is calculated through the assessment of river height and flow data:

• sites with sufficient drop (height) to provide a hydropower opportunity, mainly weirs and other man-made structures but also natural features such as waterfalls
• estimates of river flow rates at each site using Environment Agency datasets and gauging stations

The results identify that small scale hydropower opportunities are the principal resource in England and the south west, with calculated potential power outputs per site ranging from 0 – 500 kW with an exceptional few up to 1500 kW. The vast majority are of the scale of 0 – 10 kW and 10 – 50 kW. However, in its current form the resource assessment is an overestimation of hydropower potential as it is unconstrained.

Refining the dataset

Regen is piloting an assessment of the regional hydropower data in Dorset to examine the value we can add to this data and to make it more useful to local users. We are aiming to produce guidelines setting out how to further constrain the opportunities identified by the Environment Agency regional data when undertaking local assessment. These hydropower guidelines will be supplied to you once they are completed to aid your use of the Environment Agency’s hydropower data.

Accessing the GIS dataset

The south west regional hydropower datasets and GIS layers are now available from Regen SW. However the data is still currently in its original unconstrained status which results in an overestimation of the available resource potential which will require individual site studies.

Local authorities wishing to obtain the GIS layers for their own use will need to produce signed confirmation that they hold appropriate licenses. Local authorities will need to pay an administrative charge of £550 to receive the data in their preferred format. This will entitle the user to the transfer of all available data layers from the south west heat map and resource assessments.

For more information please email Josie Ashe.