Dr. Melissa Johansson

The UK and European governments are committed to reducing Greenhouse Gases by 15% by 2020 and Hydro Power, specifically small scale hydroelectric schemes has been identified as one possible renewable energy solution. Hydropower technology is mature with extended longevity, and once built is considered comparatively environmentally benign in contrast to other energy industries, especially if it uses existing weirs. Recent environmental awareness, together with government supported financial schemes, have enabled small scale residential energy projects to become a viable option and are thought to contribute to economic regeneration, social cohesion and provide education in renewable energy in local communities. The UK currently (2016) generates between 1.5-1.8% of its electricity from small hydroelectrical power, and although most of Britain’s large-scale development potential are already exhausted, there is much scope for exploiting small scale resource such as run-of-the-river schemes. Current obstacles to small hydropower schemes on existing weirs in Europe, as set out by the EU Water Directive is the potential hindrance to fish migration due to the elevated head caused by the weir. However, these small scheme, if installed in declining industrial communities, not only reduce the carbon footprint of our energy usage but can help offset the growing rise of fuel poverty and help rejuvenate local economies. One current example of a renewable energy scheme in Cardiff is the Radyr Weir Hydro Scheme which uses water flowing over an old weir from the River Taff to generate electricity. The gross head of the system has been calculated as 3.5m with a mean flow of 21.37m3/s. The turbines chosen for such a project were two Archimedes screw turbines (3.5 meters in diameter and 10 meters in length) to generate a maximum of 394kW (2 x 200kW). The annual energy yield will be approximately 1.8 million kWh per year, with an annual CO2 saving of around 785 tonnes. Although the future economics are difficult to project due to fluctuating Feed-in-Tariffs in the UK, the value of producing electricity in the winter months when it is needed most, with little to no carbon footprint cannot be quantified. In addition implementing fish friendly turbines, including fish passageways in the design will improve fish migration and a review of the current EU Water Directive is needed to encourage the development of the these small microhydro power schemes in the U.K. and Europe.

GEOLOGIST with a Ph.D in Deep Marine Sediments and 20 years experience in the oil and gas industry. Key strengths include: clastic & carbonate sedimentology (marine environments incl. deep-water (turbidites) & shallow-water (coastal plain). I am specialized in 3D image, analysis & data interpretation; facies modelling; log operations; software (Techlog & Petrel); seismic inversion & geological modelling; project planning & management. Recently I have received a Distiction in my Masters in Sustainable Energy and the Environment, at Cardiff University Engineering Department, specializing in microhydro power, and I now have my own company Geode-Energy Ltd, which is now looking to develop microhydro schemes in Wales.