Small-scale hydropower: how to reconcile electricity generation and environmental protection goals? ETC/ACC Technical Paper 2009/13

20 May 2010

This project assessed the environmentally compatible potential of small-scale hydropower (SHP) in Europe. The recently agreed target for 20% of the EU’s energy consumption to be derived from renewable energy sources by 2020 is providing a strong added impetus to deploy technologies such as SHP, however such deployment must not cause unacceptable harm to the environment. The Water Framework Directive (WFD) encourages significantly higher environmental standards than those implemented by the majority of existing SHP plant. It could likely limit the growth of new SHP plant and it could have an impact on existing SHP plant, which currently provide 9% of the EU’s electricity from renewables sources. Modelling by others suggests that SHP could provide a 50% increased contribution by 2020 but it is unclear to what extent environmental constraints have been taken into account.

In order to understand the impact that environmental standards will have on the contribution that SHP can make to the renewables target it is necessary to have an agreed methodology to assess SHP potential and an agreed approach to factoring down the potential to account for environmental constraints. The goal is to calculate a technical potential and decide how to account for the environmental constraints: (i) a requirement to implement mitigation measures such as fish passes, flow control or the undergounding of transmission wires will generally increase the cost of electricity production, making it potentially uncompetitive in the electricity market; (ii) exclusion of technically viable SHP sites because they lie within a geographically designated area (e.g. a Natura 2000 site or national park) resulting in a too high deployment density or conflict with policies. These constraints may result in a much smaller number of technically viable sites actually being realistically viable, which is what dictates the contribution that SHP will make in practice.

During 2009 an assessment was made of various SHP resource assessment methodologies to identify whether any of them would be suitable for calculating the SHP technical potential across different European countries based on hydrological data available electronically in the public domain. A number of software packages have been developed to do SHP resource assessment but most of these have either relied on site specific information or were designed for use in specific countries. We believe one of these may be adaptable for use across European countries, however this will require further investigation.

A stakeholder workshop in 2009 brought parties together to review SHP’s environmental impacts and discuss how these should be factored into calculating its environmentally compatible potential. Full information is provided in this report’s appendices. Based on feedback from this workshop, coupled with the work described above on resource assessment methodologies, in 2010 efforts are made to develop a workable methodology and apply it on a pilot basis to at least one representative European river catchment.

Prepared by: Mike Landy and James Craig (AEA, UK)

Published by: ETC/ACC, December 2009, 67 pp.