Scottish Water considers hydropower projects

An international hydropower project to review the effectiveness of hydroelectric plants in Africa and Europe has been completed by a Scottish Water engineer.

The project, conducted by environmental engineer Claire Chapman, aimed to find out about the environmental impact of modern hydropower sites, with a view to applying similar schemes in Scotland.

The findings of the ‘Harnessing Hydropower In Africa & Europe: Environmental Observations of Hydropower Plants’ report are expected to provide Scottish Water with greater understanding of environmental licensing requirements and to find out more about a ‘pumped storage’ process, where reservoirs are used to store water for times of peak energy demand and about financing models.

Interest in hydropower has increased in the UK in the past year, partly because of the introduction of the Feed-in Tariff in Britain, and as a direct result of dwindling fossil fuel supplies pushing up energy prices.

However, the in the report Ms Chapman admits that while hydropower is the lowest producer of greenhouses gases it requires “high amounts of capital and long lead in times, so is not always suitable for urgent energy demands”.

As part of the research trip, Ms Chapman spent ten days in Norway, followed by a month in Africa visiting South Africa, Lesotho, Zambia and Tanzania where she met with local operators and researched environmental sensitivities.

In the report, Ms Chapman noted that in parts of sub-Saharan Africa, where there is currently a critical availability of power, hydropower plants were running with no allowances being made for the river’s environmental requirements.

This, she said, has been exacerbated by drought conditions in some parts, as well as artificial droughts arising from water-intensive crops being planted upstream of hydropower plants.

In contrast, the report found that Norway has implemented a solution to store power in its reservoirs, which can be released at a moment’s notice, and are now capitalising on this by selling energy storage to the EU.

Similarly, in South Africa, more pumped storage sites are being constructed to allow for quick access to power.

Ms Chapman said: “Carbon-based thermal energy production is increasingly giving way to renewables – and unlike wind or ocean turbines, hydro is well established as a reliable energy source”.

The commercial arm of the water company Scottish Water Horizons (SWH) is reported to have recently started generating for the National Grid following the installation of a 52kw turbine at its defunct Touch water treatment works near Stirling.

The scheme has seen £400,000 invested and is expected to generate 300MWh a year – enough to power 50 homes.

Ms Chapman said that SWH expects to see a return on its investment within six years, while income generated from the Touch works will be reinvested into further renewable energy projects.

She added: “There is much more potential for hydro power in Scotland. There are, however, significant environmental and engineering challenges – but these are not insurmountable.

“The pumped storage solution – holding water in higher locations that can be released to generate energy when it is required – is viable as similar schemes in Norway are providing power and also are a stable investment.”

The full report can be viewed here.

Carys Matthews

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