Chapter 8

Energy Storage

Solar energy is a time-dependent energy resource. Energy needs for a very wide variety of applications are also time dependent but in a different fashion than the solar energy supply. Consequently, the storage of energy or other product of a solar process is necessary if solar energy is to meet substantial portions of these energy needs.

Energy (or product) storage must be considered in the light of a solar process system, the major components of which are the solar collector, storage units, conversion devices (such as air conditioners or engines), loads, auxiliary (supplemental) energy supplies, and control systems. The performance of each of these components is related to that of the others. The dependence of the collector performance on temperature makes the whole system performance sensitive to temperature. For example, in a solar-thermal power system, a thermal energy storage system which is characterized by high drop in temperature between input and output will lead to unnecessarily high collector temperature and/or low heat engine inlet temperature, both of which lead to poor system performance.

In passive solar heating, collector and storage components are integrated into the building structure. The performance of storage media in passive heating systems is interdependent with the absorption of energy, and we reserve discussion of part of this aspect of solar energy storage for Chapter 14.

The optimum capacity of an energy storage system depends ...

Get Solar Engineering of Thermal Processes, 4th Edition now with the O’Reilly learning platform.

O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.