scholarly journals Energy and Exergy Analysis of Ocean Compressed Air Energy Storage Concepts

2018 ◽  
Vol 2018 ◽  
pp. 1-14 ◽  
Author(s):  
Vikram C. Patil ◽  
Paul I. Ro
Keyword(s):  
Heat Transfer ◽  
Energy Storage ◽  
Heat Transfer Enhancement ◽  
Exergy Analysis ◽  
Compressed Air ◽  
Compressed Air Energy Storage ◽  
Transfer Enhancement ◽  
Energy And Exergy ◽  
Energy And Exergy Analysis ◽  
Liquid Piston

Optimal utilization of renewable energy resources needs energy storage capability in integration with the electric grid. Ocean compressed air energy storage (OCAES) can provide promising large-scale energy storage. In OCAES, energy is stored in the form of compressed air under the ocean. Underwater energy storage results in a constant-pressure storage system which has potential to show high efficiency compared to constant-volume energy storage. Various OCAES concepts, namely, diabatic, adiabatic, and isothermal OCAES, are possible based on the handling of heat in the system. These OCAES concepts are assessed using energy and exergy analysis in this paper. Roundtrip efficiency of liquid piston based OCAES is also investigated using an experimental liquid piston compressor. Further, the potential of improved efficiency of liquid piston based OCAES with use of various heat transfer enhancement techniques is investigated. Results show that adiabatic OCAES shows improved efficiency over diabatic OCAES by storing thermal exergy in thermal energy storage and isothermal OCAES shows significantly higher efficiency over adiabatic and diabatic OCAES. Liquid piston based OCAES is estimated to show roundtrip efficiency of about 45% and use of heat transfer enhancement in liquid piston has potential to improve roundtrip efficiency of liquid piston based OCAES up to 62%.

Comparative Study of Various Constant-Pressure Compressed Air Energy Storage Systems Based on Energy and Exergy Analysis

2020 ◽  
Vol 143 (5) ◽  
Author(s):  
Youssef Mazloum ◽  
Haytham Sayah ◽  
Maroun Nemer
Keyword(s):  
Energy Storage ◽  
Energy Density ◽  
Exergy Analysis ◽  
Constant Pressure ◽  
Storage Systems ◽  
Compressed Air ◽  
Compressed Air Energy Storage ◽  
Storage Medium ◽  
Energy And Exergy ◽  
Energy And Exergy Analysis

Abstract The balance between supply and demand for electricity is mainly disrupted by the growing contribution of renewable energy sources to the electrical grid since these sources are intermittent by nature. Therefore, the energy storage systems, mainly those of considerable size, become essential to restore the electricity balance. The compressed air energy storage (CAES) system is one of the mature technologies used to store electricity on a large scale. Therefore, this article discusses the energy and exergy analysis of different configurations of a constant-pressure CAES system to improve its overall efficiency and energy density. The exergy efficiency of our basic adiabatic configuration using water as thermal storage medium is 56.4% and the energy density is 12.17 kWh/m3. The results show that the CAES system using a packed bed of quartzite rock as thermal storage medium has the best efficiency (67.2%) and energy density (17 kWh/m3) among adiabatic systems. The diabatic CAES systems could have a net efficiency up to 70.1% and an energy density up to 31.95 kWh/m3 by using combustion chambers. Finally, the waste heat recovery from other installations such as a gas turbine power plant has the potential to improve the energy density to 20.53 kWh/m3 without using fossil fuel sources.

Energy and exergy analysis of adiabatic compressed air energy storage system

Energy ◽  
2017 ◽  
Vol 138 ◽  
pp. 12-18 ◽  
Author(s):  
Lukasz Szablowski ◽  
Piotr Krawczyk ◽  
Krzysztof Badyda ◽  
Sotirios Karellas ◽  
Emmanuel Kakaras ◽  
...  
Keyword(s):  
Energy Storage ◽  
Exergy Analysis ◽  
Storage System ◽  
Energy Storage System ◽  
Compressed Air ◽  
Compressed Air Energy Storage ◽  
Energy And Exergy ◽  
Energy And Exergy Analysis

Design of an Interrupted-Plate Heat Exchanger Used in a Liquid-Piston Compression Chamber for Compressed Air Energy Storage

2013 ◽  
Author(s):  
Chao Zhang ◽  
Farzad A. Shirazi ◽  
Bo Yan ◽  
Terrence W. Simon ◽  
Perry Y. Li ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Energy Storage ◽  
Heat Exchanger ◽  
Pressure Drop ◽  
Plate Heat Exchanger ◽  
Compressed Air ◽  
Compressed Air Energy Storage ◽  
Plate Heat ◽  
Liquid Piston ◽  
Compression Chamber

In the Compressed Air Energy Storage (CAES) approach, air is compressed to high pressure, stored, and expanded to output work when needed. The temperature of air tends to rise during compression, and the rise in the air internal energy is wasted during the later storage period as the compressed air cools back to ambient temperature. The present study focuses on designing an interrupted-plate heat exchanger used in a liquid-piston compression chamber for CAES. The exchanger features layers of thin plates stacked in an interrupted pattern. Twenty-seven exchangers featuring different combinations of shape parameters are analyzed. The exchangers are modeled as porous media. As such, for each exchanger shape, a Representative Elementary Volume (REV), which represents a unit cell of the exchanger, is developed. The flow through the REV is simulated with periodic velocity and thermal boundary conditions, using the commercial CFD software ANSYS FLUENT. Simulations of the REVs for the various exchangers characterize the various shape parameter effects on values of pressure drop and heat transfer coefficient between solid surfaces and fluid. For an experimental validation of the numerical solution, two different exchanger models made by rapid prototyping, are tested for pressure drop and heat transfer. Good agreement is found between numerical and experimental results. Nusselt number vs. Reynolds number relations are developed on the basis of pore size and on hydraulic diameter. To analyze performance of exchangers with different shapes, a simplified zero-dimensional thermodynamic model for the compression chamber with the inserted heat exchange elements is developed. This model, valuable for system optimization and control simulations, is a set of ordinary differential equations. They are solved numerically for each exchanger insert shape to determine the geometries of best compression efficiency.

Sign in / Sign up

Export Citation Format

Share Document