Abstract: The invention relates to a system and a method for storing electrical energy which are based on a closed thermodynamic cycle. They make it possible to store electrical energy in a very efficient, cost-effective, and safe manner. No environmentally hazardous or expensive materials are required. The system comprises a compressor, a turbine, and two packed-bed storage units which are operated at different temperature levels. In order to load the packed-bed storage units, the cycle is operated as a counterclockwise heat pump process. In this process, the heat generated at the outlet of the compressor is expanded at a high temperature level into a first packed-bed storage unit and stored therein. The “cold” produced during the subsequent expansion of the gaseous working medium in a turbine is stored in a second packed-bed storage unit. This requires mechanical energy which is provided by an electrical machine. In order to discharge the energy storage system, the cycle is operated in reverse (i.e.

Abstract: The invention relates to a system and a method for storing electrical energy which are based on a closed thermodynamic cycle. They make it possible to store electrical energy in a very efficient, cost-effective, and safe manner. No environmentally hazardous or expensive materials are required. The system comprises a compressor, a turbine, and two packed-bed storage units which are operated at different temperature levels. In order to load the packed-bed storage units, the cycle is operated as a counterclockwise heat pump process. In this process, the heat generated at the outlet of the compressor is expanded at a high temperature level into a first packed-bed storage unit and stored therein. The “cold” produced during the subsequent expansion of the gaseous working medium in a turbine is stored in a second packed-bed storage unit. This requires mechanical energy which is provided by an electrical machine. In order to discharge the energy storage system, the cycle is operated in reverse (i.e.

Abstract: Proposed is a cheap and durable high-temperature heat store which utilizes ambient air as a heat carrier medium and which is at least partially filled with a granular and/or porous storage medium (6).

Abstract: A high-temperature thermal storage device has a crucible, an induction heating device, a tubular duct in which a liquid and/or gaseous heat carrier flows, and an electrically conductive storage medium filled into the crucible that fills the crucible at least partially. The induction heating device, when electric energy is applied, heats the storage medium. The tubular duct passes at least partially through the storage medium. The storage medium is a molten metal and the thermal storage device has an operating temperature exceeding 700° C. The thermal storage device readily provides steam, be it saturated steam or superheated steam, fulfilling all parameters required for the operation of a conventional thermal power station.

Abstract: Proposed is a cheap and durable high-temperature heat store which utilizes ambient air as a heat carrier medium and which is at least partially filled with a granular and/or porous storage medium (6).

Abstract: The invention relates to a bush widening apparatus and a process by means of which it is possible to partially, in sections, forge at relatively low investment costs large and heavy bush blanks by means of a motor-driven, e. g. hydraulic, forming tool, and during which process both the diameter and the height of these banks increase in size.