As the green transition accelerates, the need for energy storage is increasing. Hydrogen storage and batteries are seen as particularly important technologies. Building an energy storage facility is a big investment - but there are also opportunities to save and make money.
Renewable energy sources such as solar and wind are becoming an increasingly important part of the energy mix. This increases the need for energy storage solutions that can store energy until it is needed. To maintain a reliable power supply, energy must be available at all times, not just when weather conditions are favorable. Energy storage can help the manufacturing company with 24/7 production and the hospital with life-support equipment to secure their power supply.
Multiple Energy Storage Technologies
A wide range of energy storage technologies are available today. Pumped water storage, mechanical motion storage, magnetic storage, and thermal storage are some examples. However, the most popular technologies are batteries and hydrogen storage.
– Traditionally, large-scale energy storage has been done with fossil fuels such as oil. This is a very efficient form of storage, but the green transition means that we need to find new sources of energy that are not burdened by carbon emissions. Batteries have emerged as a solution, and hydrogen has also become more interesting. Depending on the circumstances and application, different technologies are suitable for different purposes, says Claes Winzell, business developer at RISE.
– Simply put, batteries are heavy and expensive, so it is often not cost effective to use this solution on a large scale. Batteries are good for smaller applications, such as in an electric car, and hydrogen storage is good for large applications. Hydrogen may also be better for long-term storage. However, the energy losses in the conversion from electricity to hydrogen and from hydrogen back to electricity are quite high. This also has to be taken into account, says Gustav Green, research and development engineer at RISE.
Holding an energy storage facility allows you to provide ancillary services to the electricity grid and be part of the balancing market
Energy storage generates revenue
Gustav Green and Claes Winzell emphasize that it is easy to become cost-driven when you start thinking big – regardless of the technology you choose. But having energy storage also opens the door to new revenues.
– With energy storage, you can provide ancillary services to the grid and be part of the balancing market. That plays a very big role when we're talking about industry, because of course you want to make money there, says Gustav Green.
– We usually talk about local benefits and benefits to the larger system. For example, if you have your own solar panels on your property and an energy storage system, you can use the stored solar energy at night. This is a local benefit, says Claes Winzell and continues:
– Looking at the benefits for the larger system, energy storage can act as a regulator and help balance the electricity grid. When electricity demand is higher than electricity production, energy storage can kick in and replenish the supply. If production is higher than consumption, it is possible to reduce the input from the energy storage. Svenska Kraftnät will compensate you financially for providing this support service.
Evaluate your own needs
To implement an energy storage system in your organization, you need to evaluate your own needs. How do you need the energy - high power for a short time, or a constant flow for a long time? Where is it possible to install an energy storage system? What are the grid connection points there? There are many parameters to consider and calculate. This is where RISE can help.
– We have a lot of knowledge and can help companies and organisations that want to build an energy storage facility, for example, with investigative work in the form of feasibility studies and dimensioning, says Claes Winzell.
– We see a need for more knowledge along the entire value chain, from energy production to distribution and utilization. This is where we can help and also contribute with a systems perspective. We also have many laboratories, including one where we can test hydrogen components, for example. We are both a testing and an expertise partner, says Gustav Green.
From dams to magnetic fields - energy storage technologies
Energy storage is the process of saving energy for later use. It enables a balance between energy production and demand. Batteries and hydrogen storage are currently the most discussed, but there are others:
Hydroelectric dam water reservoirs
The method requires two water reservoirs at different heights. Excess electricity is used to pump water from the lower to the higher reservoir. When electricity is needed, the water is released from the higher reservoir to the lower one and drives a generator.
Storage in the form of mechanical movement
Large flywheels are set in motion in hydroelectric or nuclear power plants, for example. The flywheels drive generators.
Magnetic storage
Technology where energy is stored in magnetic fields. Achieved by using superconducting materials that are magnetised. When there is a need to recover the stored energy, the magnetic energy is removed.
Compressed air storage
Air is compressed and stored in underground large liquid tanks. When electricity is needed, the compressed air is released and used to drive a generator.
Thermal energy storage
Materials with high heat capacity, such as molten salt, are used to store thermal energy. It is also possible to store energy using cold. An example of this is using surplus electricity to freeze water. When there is a need for cooling energy, heat from process environments can be used to melt the ice, which then emits cold.
