Session: 03-03 Pumped Thermal Energy Storage

Paper Number: 107521

107521 - Analysis of Renewable Energy Integrated Pumped Thermal Energy Storage Systems of Renewable Energy Integrated Pumped Thermal Energy Storage Systems 

The increased penetration of fluctuating renewable energy sources causes an imbalance between the supply and demand of energy, reduced capacity margins, and congestion of electricity networks. Pumped thermal electricity storage systems are proposed as an option for low-cost and long-duration electrical energy storage. In this paper, different novel configurations of pumped thermal electricity storage systems are proposed which can integrate excess thermal energy from different renewable thermal energy sources, e.g. concentrated solar power and geothermal energy plants, as well as excess electricity from direct electricity generating renewable energy sources, e.g. solar photovoltaic and wind energy plants. The proposed configuration can also be used as a retrofit option to existing conventional fossil fuel-based power plants. Conventional two-tank sensible heat storage is used as a thermal energy storage system and a widely investigated Joule–Brayton pumped thermal electricity storage system is used as an excess electricity charging system. Different discharging cycles, including a Joule–Brayton system and a conventional steam Rankine cycle system, are considered.

As a case study, different configurations of the pumped thermal electricity storage system integrating concentrated solar power (considering the Heliostat system) and solar photovoltaic plants for the location of Cape Town, South Africa were investigated. First, the screening of different options was done using a model developed in Engineering Equation Solver (EES). Then, the detailed annual simulations and optimizations were performed for a selected configuration based on the initial screening. For the analysis of the concentrated solar power and solar photovoltaic systems, the system advisor model (SAM) was used. Simplified models using the Engineering Equation Solver were used for the other components. Python was used in order to link the components/subsystems together and estimate the electrical output of the combined system during each time step. The overall operational strategy of the plant was developed and based on that the annual simulations were performed.

The results of the case study suggest that from a techno-economic perspective, the proposed system performs better compared to a stand-alone concentrated solar power plant with a thermal energy storage system. The proposed system also achieves a higher capacity factor compared to those of stand-alone plants.

Presenting Author: Simone Parisi Technical University of Denmark

Presenting Author Biography: Simone Parisi is a Ph.D. student at the Technical University of Denmark. His research focuses on turbomachinery design for thermal energy storage applications, including concurrent cycle and machine optimization and reversible compressor-turbines. His education includes a B.Sc. in Aerospace engineering and an M.Sc. in Mechanical Engineering, both earned at the Polytechnic University of Milan, Italy. During his M.Sc. he also graduated from the honors program of the Alta Scuola Politecnica, Italy.