The expansion and upgrade of existing hydropower plants represents a possible alternative to wind farm development. So-called environmental design makes it possible to conserve natural habitats while at the same time generating renewable energy profitably. Photo: alxpin/iStock

More hydropower and a better environment

  • Published 21.11.19

The Norwegian public authorities’ estimates of the potential to expand the country’s power plants are probably too low. A new approach is creating opportunities for increased production while also enhancing environmental aspects.

The heated debate about onshore wind farm development has led to animated discussions about other renewable sources of electricity generation. Not least, a debate about how much additional power Norway can extract by upgrading and expanding existing hydropower facilities as a possible alternative to wind farm development plans.

The public authorities’ estimates for expansion potential are regarded as moderate. However, Norwegian researchers have now developed approaches involving so-called environmental design that make it possible to conserve natural habitats, while at the same time generating electricity profitably.

The Sira-Kvina Power Company is among the first to apply the new approach.

Salmon and power plants share the water

The company is planning to boost power production by transferring water from the Knabenåni tributary to an existing reservoir. At the same time, some of this extra water will be used to improve conditions for salmon in the Kvina river. Moreover, other measures such as better migration devices, combined with the establishment of spawning and juvenile growth areas, will be implemented to boost the fish population.

As a result of all this, the Sira-Kvina Power Company anticipates increasing its power production by 140 GWh (equivalent to the needs of 5,600 households) while simultaneously achieving a two-fold increase in the salmon population in the Kvina river.

This approach is creating opportunities for similar benefits in other catchments as well. The method is ideally suited to the upgrade and expansion of hydropower facilities and may thus raise the threshold for the number of initiatives of this kind that can be implemented. This is why the estimates issued by the authorities for expansion opportunities linked to hydropower in Norway are regarded as being too low.

Study of implemented expansion projects

Hydropower expansion potential, initially highlighted by a scientific study published by NTNU, is now the subject of heated debate. The conclusion of the study, presented on 10 May in the financial daily Dagens Næringsliv (DN) by Professor Leif Lia, is that upgrades to, and expansion of, Norway’s existing hydropower system will allow it to generate between 15 and 20 per cent more electricity than at present.

This is equivalent to between 22 and 30 terrawatt hours (TWh), which is as much electricity as all Norwegian onshore wind farms currently in the planning stage.

The study’s conclusion is based in on boosting production that many plants have already achieved following upgrade and expansion initiatives. In the newspaper article, the authors emphasise that politics and environmental factors will determine how much of the 22 to 30 TWh increase can be achieved.

Debate about potential

In a reply, also published in DN, Kjetil Lund, Director of the Norwegian Water Resources and Energy Directorate (NVE) points out that his organisation has previously estimated that the technical/economic potential available from upgrades and expansions in the Norwegian hydropower system is about six terrawatt hours.

He concludes his article by saying that unless society is willing to accept the major destruction of natural habitats, or introduce a very generous tax regime, it is unlikely that the potential for increases in hydropower generation from existing plants will ever reach the orders of magnitude claimed by Professor Lia.

Net environmental benefit

It is true that the expansion of hydropower plants impacts on nature due to measures such as the design of new water conduits, dam enlargement and the linkage of previously unregulated lakes, tributaries and streams.

However, the deep-rooted assumption that every expansion project is certain to have a negative environmental impact is now being turned on its head – thanks to the new approach involving environmental design.

The method has been developed by SINTEF, NTNU and the Norwegian Institute for Nature Research (NINA) as part of a national research initiative called CEDREN. By organising our knowledge of power generation, economics, societal interests and environmental factors within a system, the new method makes it possible to boost power generation from any given catchment while at the same time producing a net environmental benefit.

Diagnosis and cure

Environmental design is like taking the catchment and the power plant to the doctor. It first involves making a diagnosis of what is failing to function adequately. Then we start looking for opportunities to expand and make improvements with the help of measurements and computational tools that are integrated into the methodology. Such tools are like “stethoscopes” and “x-ray examinations” that help us to find the “right medication” for both power generation and the environment.

In the light of this, we are now proposing that environmental design should be applied to determine how much upgrade and expansion potential should be achieved within the hydropower system.

The answer will probably lie somewhere between the NVE’s moderate estimate of six TWh and the  NTNU researchers’ maximum value of 30 TWh.

A golden opportunity

Many Norwegian power plants are so old that their licence terms and conditions are now up for revision. Guidelines require that expansions shall be assessed as part of these revisions. However, such assessments are unfortunately not always being carried out.

The opportunities offered by environmental design are providing Norway with the chance to revisit this requirement. By doing so we can conserve our valuable natural habitats while also obtaining renewable energy for the future electrification of transport systems and other sectors within society.

We must take the natural world into account as part of all future renewables initiatives such as hydropower and solar energy, as well as onshore and offshore wind power developments. Environmental design can be applied both in the development of new plants, and when considering the ageing of existing facilities.

This article was first published in the financial daily Dagens Næringsliv (DN) on 26 August 2019, and is reprinted here with the permission of DN.