Solar Energy Storage Program: FY79 Annual Report

This report summarizes the SERI Solar Energy Storage Program, which made a strong start in FY79. In support of the joint DOE Thermal Energy Storage for Solar Thermal plan, a ranking methodology was developed in the Thermal Storage Requirements Task for selection of thermal energy storage technologies for solar thermal applications. The ranking is based on cost and performance data, and a request for proposals was written in FY79 to be used in competitive selection of a subcontractor to generate this data. Also, thermal storage value data based on costs of alternative energy systems were generated for electric power plants and will be used for cost goals as a preliminary thermal storage screening tool. In the future, this task will provide support to key decision points in the joint multiyear program plan. In the Thermal Storage Development Task, a survey was completed of thermal energy storage technologies, projects, and economics. An analysis was then made of latent heat storage for solar heating based on previous system simulations. The only major advantage shown for latent heat storage is a reduced storage volume and not the improved solar system performance frequently postulated. Therefore, latent heat storage must be competitively priced with sensuible heat options. Direct contact latent heat storage offers satisfactory low-cost potential and has additional merit in that the concept could be used for a wide range of temperatures.