Pumped-storage power plants

We are assessing possibilities to build pumped-storage power plants in Northern Finland. New hydroelectricity accelerates Finland’s energy transition and secures the uninterrupted flow of society’s everyday life.

Hydropower’s regulating capability is increasingly important to our energy self-sufficiency and security of supply as Finland transitions from fossil fuels to renewable energy sources.  The increasing variable wind and solar power production rapidly changes the Finnish energy system. In addition, the electrification of society and future industrial investments will inflate electricity demand. Thus, there is a growing need for regulating power that balances the energy system and for large-scale electricity storages.

Pumped-storage power acts as a water battery that balances Finland’s electricity system. Pumped-storage power plants reduce the price of electricity for Finnish users – for households, companies and industries alike. They also stabilise fluctuations in electricity prices and improve the predictability of pricing, thus enabling new industrial investments in Finland.

Spikes in electricity consumption and production are mainly balanced through hydropower

The current amount of regulating power is not enough to balance the fast increase of wind and solar power, which are sensitive to weather. According to Fingrid’s predictions, the capacity of wind power could reach up to 21,000 megawatts (MW) by the end of the decade, while the overall installed production capacity of electricity in Finland was approximately 20,000 megawatts in 2022. At the same time, electricity consumption is expected to increase up to 49% by 2040. That is why more hydropower – the best kind of regulating power – is needed.

Sources: Fingrid, Energy Authority

Ailangantunturi pumped-storage power plant

We are continuing the preliminary planning of the pumped-storage plant at Ailangantunturi in Kemijärvi.

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Pumped-storage power is a well-known technology

Pumped-storage power is a well-known and used technology, enabling the storage of electricity with an exceptionally high efficiency. Pumped-storage power plants can produce electricity when demand is high or if there is a malfunction in the electricity system. On windy and sunny days, or when there is an oversupply of electricity, a pumped-storage plant pumps water back to the upper storage.

How pumped-storage power works

  • Water in the upper storage flows through turbines into the lower storage – a regulated lake or river in the case of Kemijoki Oy’s pumped-storage plants. Depending on capacity, draining the upper storage takes from 7 to 9 hours.
  • When electricity demand or prices are low, e.g. at nighttime, the pumped-storage plant pumps water back to the upper storage. This also takes around 7-9 hours.

Assessing the environmental impacts of pumped-storage power plants

Clean energy has a crucial role in mitigating and controlling climate change. The more we can use carbon-free hydropower, the more we can also use other renewable energy sources. However, all forms of energy production have an impact on the environment.

We assess and strive to minimise the environmental impacts of pumped-storage plants and how pumped-storage power might affect biodiversity. Assessing the impacts requires site-specific modelling and thorough evaluations.

  • Pumped-storage plants require water supplies that cover natural habitats.
  • Pumped-storage power uses land efficiently. The area it requires is relatively small: the size of the upper storage is close to a square kilometre, which equals the area needed for 1−2 wind farms.
  • The building structures of a pumped-storage plant are mostly underground.
  • Pumped-storage power plants have an impact on the changes in currents, for example.

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