Title: Performance of an Isobaric Hybrid Compressed Air Energy Storage System at Minimum Entropy Generation

Abstract

Efficient, large-scale, and cost-effective energy storage systems provide a means of managing the inherent intermittency of renewable energy sources and drastically increasing their utilization. Compressed air energy storage (CAES) and its derivative architectures have received much attention as a viable solution; however, optimization objectives for these systems have not been thoroughly investigated in the literature. In this work, a hybrid thermal and compressed air energy storage (HT-CAES) system is investigated that mitigates the shortcomings of the otherwise attractive conventional CAES systems and its derivatives—shortcomings such as strict geological locations, low energy densities, and the production of greenhouse gas emissions. The HT-CAES system allows a portion of the available energy to operate a compressor and the remainder to be converted and stored in the form of heat through joule/resistive heating in a high-temperature, sensible, thermal energy storage medium. Internally reversible and irreversible HT-CAES system assumptions were investigated, in addition to regenerative and non-regenerative design configurations. Several system optimization criteria were examined—including maximum energy efficiency, maximum exergy efficiency, maximum work output, and minimum entropy generation—with a focus on whether the latter may lead to conclusive design guidelines in a real system. It is shown that an HT-CAES system designed based on amore » minimum entropy generation objective may operate at a lower energy and exergy efficiency as well as lower output power than otherwise achievable. Furthermore, optimization objective equivalence is shown to be limited to certain design conditions.« less

Authors:

Houssainy, Sammy  ^[1];

• Search DOE PAGES for author "Houssainy, Sammy"
• Search DOE PAGES for ORCID "0000-0002-7738-3658"

Janbozorgi, Mohammad ^[2]; Kavehpour, Pirouz ^[2]

---

+ Show Author Affiliations

1. National Renewable Energy Lab. (NREL), Golden, CO (United States)
2. Univ. of California, Los Angeles, CA (United States)

Publication Date:

Tue Mar 10 00:00:00 EDT 2020

Research Org.:

National Renewable Energy Lab. (NREL), Golden, CO (United States)

Sponsoring Org.:

USDOE Office of Energy Efficiency and Renewable Energy (EERE), Energy Efficiency Office. Building Technologies Office; California Energy Commission

OSTI Identifier:

1677460

Report Number(s):

NREL/JA-5500-75543
Journal ID: ISSN 0195-0738; MainId:6397;UUID:6fcafc1b-0915-ea11-9c2a-ac162d87dfe5;MainAdminID:18650

Grant/Contract Number:  

AC36-08GO28308; EPC-14-027

Resource Type:

Accepted Manuscript

Journal Name:

Journal of Energy Resources Technology

Additional Journal Information:

Journal Volume: 142; Journal Issue: 5; Journal ID: ISSN 0195-0738

Publisher:

ASME

Country of Publication:

United States

Language:

English

Subject:

25 ENERGY STORAGE; buildings; CAES; minimum entropy generation; compressed air energy storage; hybrid energy storage; energy storage; thermal energy storage; alternative energy sources; energy conversion/systems; energy storage systems; energy systems analysis; heat energy generation/storage/transfer; renewable energy