Thermal Energy Storage

This project aimed to develop a modular, thermal electricity storage system. The project also involved a case study of the value creation / business model of thermal energy storage on the basis of information from a specific wind farm.

Challenge

Storing green energy is the last major technical challenge on the road to a 100% climate-friendly energy supply. As green forms of energy increase and decrease in production, depending on e.g., wind, there is a need for us to be able to store the green energy over time. In this way, the energy system can supply electricity at all times of the day, every day of the year – even when it is not windy. Currently, it is possible to store wind energy over time to a limited extent, but it is not profitable on a large scale. A number of companies and knowledge institutions are collaborating to develop a modular, thermal electricity storage system. The project also involved a case study of the value creation / business model of thermal energy storage on the basis of information from a specific wind farm.

Solution

Energy storage has three time perspectives: short, medium, and long terms. Short-term energy storage is from minutes to hours; medium-term is from hours to a week, and long-term seasonal storage is from a week to half a year. The Thermal Energy Storage project has focused on a solution for medium-term energy storage.

The partners in the project developed mathematical models for a modular thermal energy storage system. The system, which was tested as a prototype on a scale of 1:10 in the project, consists of crushed stones that can absorb heat produced with electricity from e.g., wind energy. The energy can be stored for many days as the stones are stored in large insulated metal cylinders. Then the heat can be converted back to electricity when needed.

Thermal Energy Storage also involved a study of the business model for thermal energy storage based on information from a specific wind farm.

Project deliverables

New cost-effective form of energy storage.