HTSTORAGE

1. Improve the performance of molten salt. Molten salts are a thermal storage medium that is used a great deal in thermosolar plants. They are economical and durable and they can be used in a wide temperature range, between 250º and 600ºC.
2. PCM (phase change material) concepts are being developed to try and improve the energy density and thermal behaviour of the collector. Phase change materials, or PCM, use the energy associated with the change from a liquid to solid state, also called latent heat of fusion. PCMs are encapsulated and put into packing in the tank and pass their heat onto the working fluid that flows outside.

A versatile test infrastructure has been built for fluid air that may reach temperatures of 600ºC to validate the PCM concepts developed, among other applications. The system consists of

• A fan that provides ambient air for the system • A flow metre
• An air heating element
• A network of high temperature conduits
• A small scale collector that different innovative filler materials are tested in • High temperature valves for alternately charging and discharging the collector
• Pressure and temperature control and measurement instrumentation

The results of the project have made it possible to validate the research concepts and create lines of development that will be continued in the future that are geared towards massive energy storage for electrical grids.

The systems will be necessary in the next decade to be able to integrate renewables into the energy system at a large scale and meet regional and national goals.