EnBW is installing a 100MW large-scale battery storage system at its power plant site in Marbach, Germany.
With a capacity of 100MWh, it will be able to cover the electricity needs of around 12,500 households for 24 hours, said the developer, but will not be used to supply a single city.
Instead, EnBW said it will represent a significant factor in the entire southern German electricity grid due to its connection to the Transnet BW transmission grid.
It will be by far the largest battery storage system in the company’s generation sector to date.
Construction of the plant is scheduled to begin next year, with commissioning planned for the end of 2025.
“With the increasing share of electricity from renewable sources such as wind and solar energy, it is becoming increasingly important to be able to store energy and make it available again at another time,” said EnBW head of portfolio development in generation Michael Class.
“This so-called disposable power, which can be made available on demand, plays a central role in the future-proof transformation of energy generation. In this way, the weather-related fluctuating generation from renewable energies and the actual demand in the grid can be reconciled.”
Head of battery system solutions at EnBW Arnim Wauschkuhn added: “They store electricity from the grid when larger amounts of electricity are available and can feed it back into the grid in seconds if necessary.” The company said this means battery storage systems fit ideally into the system of available power, together with pumped storage plants and hydrogen-capable gas-fired power plants, for example.
The latter are particularly needed for prolonged dark doldrums – for example, when the wind does not blow or shine for several days in winter.
“Wind turbines and solar plants work hand in hand with flexible generation plants and make it possible to supply energy entirely from renewable energies,” said Class.
Wauschkuhn added: “The timing for this project is ideal.
“Battery modules have become significantly cheaper. At the same time, the need for short-term flexibility on the energy markets is increasing.
“Both together lead to an increase in profitability for such a major project.”
The large-scale battery storage facility in Marbach will be equipped with lithium iron phosphate batteries, in which no cobalt is used.
The plant will be built in the southern part of the existing power plant.
EnBW operates a grid stabilisation hub for the transmission grid for TransnetBW on the western part of the site.
These and the large-scale battery storage system share the existing infrastructure, which leads to synergies in the project, said the company. This includes, for example, the grid connection.
Battery storage systems play an important role in EnBW’s generation sector, it added.
They are included as standard in new solar park projects (pictured), for example to enable more flexible feed-in. Corresponding storage systems have already been installed at several locations.
Wauschkuhn added: “We are also planning further large battery storage projects.”