Hybridization of non-manageable renewable energy plants with compressed or liquefied air storage

Abstract

A kind of energy storage proceeding from renewable sources is presented. It has been studied the storage, in the form of Compressed Air Energy Storage Systems (CAES) or Liquefied Air Energy Storage Systems (LAES) of the renewable electricity that, at the time it is generated, it is not delivered to the network because of technical or economic reasons, or saturation. The possibility of using an artificial storage system allows the installation not to be conditioned by the availability of a natural reservoir. This article focuses on the use of artificial storage systems, mainly for small power wind farms (about 30 kW), so storage systems will alternatively be called CAES or SCAES and LAES or SLAES (S from “small”) CAES systems advantages and disadvantages of each different thermodynamic cycle are studied. One of CAES systems higher limitations is the huge volume needed to store air mass enough. Instead of storing gaseous phase air, much more energy density can be accumulated by storing air in liquid phase (LAES). LAES system functioning is similar to CAES one. Liquid air is produced in an air liquefying plant when there is an excess of energy or it is not interesting to drop it into the network Some LAES systems advantages are storage volume reduction for the same energy density and the possibility of storing at about atmospheric pressure.