Pumped Hydro Storage


The World’s Most Sustainable Balancing Power Enabling a Fossil-Free Generation

Long experience

Pumped Hydro’s and SENS team has an extensive experience of renewable energy development and planning

Focus on the future

We are a growing company with co-workers that are all passionate about the same thing – to enable the energy transition and a sustainable future


of all stored electricity is Pumped Hydro




years life-cycle

Lowest cost of storage

Low environmental impact

Large-scale long-term energy storage

The technology works by flowing water through corrosion-resistant pipes between an upper and a lower reservoir.

By constructing the reservoirs in underground mines, the costs are low and the environmental impact is minimal. We use technology and our understanding of the electricity market to design and optimise facilities that are adapted to local market and operating conditions. At the rate that the energy transition is moving, electricity production will need to be doubled within the next 10-15 years. With our portfolio of energy solutions, we can reduce the problem of insufficient power and provide consumers with electricity regardless of whether the sun is shining or the wind is blowing. Effective energy storage is simply a fundamental factor in driving the green transition forward.

Cave with water

Storage technologies

With a growing share of weather-dependent electricity production, price volatility increases on the electricity market at the same time as there is a growing need for frequency regulation in the electricity grid.

Competitive energy storage must be cheap, have a high degree of efficiency and be able to respond quickly to changes in the electricity grid. It must also have a long life cycle, low environmental impact, and a long discharge time. The only existing technology that meets these requirements is pumping power in mines, which SENS is alone in offering.

Stora batterier i solnedgång

Our solution

SENS's solution is based on an understanding of the electricity market and future revenue streams for pumped storage plants. We have translated this into a software to simulate revenue streams from electricity trading and balancing services for the electricity grid. We use the knowledge to design and optimise facilities. These are easily adapted to local market and operating conditions.

Each facility has a unique and customised operating schedule. This maximises the utilisation of the energy storage to the benefit of its owner. The technology itself is proven and consists of pumps, generators and turbines in a synchronised system. With the help of this, water is moved in a closed system through corrosion-resistant pipes between an upper and a lower reservoir. By constructing the reservoirs in underground mines, the cost of these fires and the environmental impact are minimal.

An illustration of how pumped hydro storage works.

SENS can help you develop a solution for a more sustainable and reliable power system. Contact us and we will tell you more!

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