A Closed Sulfur-Sulfuric Acid Cycle to Store Solar Energy

A Closed Sulfur-Sulfuric Acid Cycle to Store Solar Energy

Many researchers around the world are focusing on the renewable energy sources for producing energy. With the same aim, a research team at the Karlsruhe Institute of Technology, with their European associates, has designed a pioneering sulfur-based storage device for solar power. A locked sulfur-sulfuric acid cycle is developed for the extensive chemical storage and overnight usage as a fuel of the solar power. In the long-term, this may be the foundation of a cost-effective renewable energy source that has a potential of offering base-load power.

A Closed Sulfur-Sulfuric Acid Cycle to Store Solar Energy

Professor Dimosthenis Trimis said, “Solar power plants efficiently capture process heat and sulfur may be an apt storage substance to utilize this power for base-load electricity generation. Sulfuric acid and sulfur are used in several industrial applications. There are already established processes such as flue gas desulfurization, sulfuric acid production, or vulcanization. There are large kits available of process technologies to use the sulfur combustion as a continuous source on an industrial scale.”

The enduring aim of PEGASUS is the establishment and illustration of an inventive solar power tower facility. A solar absorber is merged with a thermochemical solar power storage device on the basis of sulfuric acid and elementary sulfur. The method will be confirmed under actual circumstances at the Jülich Solar Power Tower Facility in Germany.

Elementary sulfur is formed by the alteration of sulfur dioxide into sulfuric acid and sulfur, i.e., disproportionation of sulfur dioxide. The solar power plant’s focused sunlight provides the process heat with the temperature and energy needed to shut the sulfur cycle and to transform sulfuric acid again into sulfur dioxide in the existence of appropriate catalysts.

Prototypes of the important parts, such as the sulfuric acid evaporator, solar absorber, sulfur burner, and sulfur trioxide decomposer are under development. Substances needed for heat transfer, storage & absorption, and for the catalysts will be validated for long-term stability and efficiency.

The notion imagined for solar power tower facilities is illustrated by the use of a low-priced heat storage medium. Utilizing the captured energy in a burner makes these solar power plants competent of supplying base-load power.