High-temperature thermal storage device with induction heating and molten metal, and thermal storage-composite system

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.

Description

BACKGROUND OF THE INVENTION[0001]The invention relates to a high-temperature thermal storage device with induction heating, a thermal storage composite system and a process for operating the high-temperature thermal storage device and the thermal storage composite system.[0002]In the context of the invention, the term “storage device” is used synonymously with the term “thermal storage device”.[0003]When storing thermal energy in the form of high temperature heat, exergy is lost during charging and discharging of the thermal energy storage device.[0004]This exergy loss arises because the temperature level, at which the storage device was charged, is no longer attained when discharging the storage device. The magnitude of this effect depends on the storage technology selected, the (heat carrier) media used, and the design of the heat exchangers involved.[0005]In thermal storage devices tested and used to date for solar thermal power stations, charging of the storage material is perfo...

AI Technical Summary

Benefits of technology

The invention is a high-temperature thermal storage device that uses electric energy to charge and is able to tolerate very high temperatures. This allows it to operate at a high temperature that is higher than the temperature of steam at the turbine inlet. This ensures optimal output and efficiency of the turbine. Additionally, the device does not pose any problem of re-melting solidified aluminium, which is a great advantage compared to molten salt.

Problems solved by technology

When storing thermal energy in the form of high temperature heat, exergy is lost during charging and discharging of the thermal energy storage device.

This exergy loss arises because the temperature level, at which the storage device was charged, is no longer attained when discharging the storage device.

As a result thereof, exergy losses arise both during charging as well as during discharging of the storage device.

This is to say, if the steam parameters at the turbine inlet are no longer attained due to the exergy losses in a thermal storage device, the output and efficiency of the steam turbine will decrease and, consequently, also that of the power station.

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