Technology

The energy storage system we have developed converts electrical energy into potential energy bylifting the mass modules from the lower storage to the upper storage. The potential energy isconverted back into electricity by bringing down the mass modules for the upper storage.

The system can be used, for example, to balance electricity production and consumption in the balance frequency markets. Our systems can also be directly connected to renewable energy production systems, such as wind power and solar power, making it possible to sell the produced energy the electricity market at a more productive time.

Our technology is also suitable for long-term energy storage because the stored energy does not discharge by itself. The gravity battery we have developed is reliable and long-lasting. The operating life of our system is even more than 50 years.

Operating principle

Elevator system

  • The elevator system is used to move mass modules between the lower and upper warehouses.

Storing electrical energy as potential energy

  • The mass modules are lifted by electric motors from the lower warehouse to the upper warehouse.
  • The amount of stored energy can be determined directly by the weight and height difference of the modules of mass. E = mgh.

Conversion of potential energy into electricity

  • The mass modules are brought down from the upper storage to the lower storage, in which case the electric motors act as generators, producing electricity for the power grid.

Storage system

  • The elevator system is connected to a conveyor located in the storage areas.
  • When storing, the mass modules are moved from the conveyor to the storage area, either with the help of hoists shown in the video or with the help of a transfer system developed by us.
  • When unloading inventory, the system works in the opposite direction.
  • Storage is carried out in an energy-efficient manner to achieve maximum overall efficiency.

Applicability

Locations

Our gravity batteries can be built almost anywhere there are height differences, thanks to the flexibility of our technology.

  • Queries
  • Mines
  • Mountainsides
  • Cliffs

Customers and marketplaces

Our energy storage facility can be connected directly to the electricity grid, allowing it to operate in the electricity market.

  • Electricity market
  • -day-ahead market
  • -Reserve markets
  • Renewable energy producers
  • Factories and plants

Benefits

Energy storage evens out fluctuations in electricity prices by balancing production and consumption. The ordinary citizen will benefit from our energy reserves by reducing the marketprice of electricity. The operator of our plants benefits financially from our gravity battery. With current fluctuations in electricity prices and reserve markets, the payback period will be less than 10 years.

Benefits of technical solutions.

  • Installation is possible almost anywhere with height differences thanks to easily adaptable solutions.
  • It is easy to increase the energy capacity (MWh) of a gravity battery by increasing the number of mass modules.
  • Efficiency can be increased by increasing the number of elevator systems.

Environmental friendliness.

  • No need for rare and environmentally harmful minerals or other substances.
  • Reduces dependence on fossil fuels.

Benefits compared to other energy reserves.

  • Compared to electrochemical batteries:
  • -No need for rare earth minerals.
  • -Cheaper to implement.
  • Compared to pumped storage plants:
  • -Smaller land area is needed.
  • -No need to build reservoirs.

Specifications

Efficiency

The efficiency of a gravity battery is affected by the height difference at the installation site and the desired capacity. The greater the height difference between the warehouses, the better the overall efficiency is achieved. The smaller the energy storage (capacity – MWh) inrelation to the production capacity, the better the efficiency is achieved.

  • Total efficiency approx. 71%
  • Conversion of electricity into potential energy 87%
  • Conversion of potential energy into electricity 82%

Mass modules

  • Mass modules can utilise the aggregate of the site, such as the rock material of a quarry.
  • Mass modules can be made solely of stone, eliminating the need for environmentally harmful cement.

Our gravity battery in numbers:

  • Efficiency 71%
  • Power up to 50 MW
  • Storage capacity up to 150 MW
  • Response time (100%) 10 seconds
  • Service life 50 years
  • Investment costs 100 €/kWh and 500 €/kW