{"title":"Exergetic comparison of a novel to a conventional small-scale power-to-ammonia cycle","authors":"Pascal Koschwitz, Daria Bellotti, Cheng Liang, Bernd Epple","doi":"10.1504/ijex.2023.134607","DOIUrl":null,"url":null,"abstract":"Green ammonia is a promising carbon-free energy vector and means to store hydrogen efficiently. Employing the software Aspen Plus®, this work presents an exergetic comparison of a novel small-scale power-to-ammonia system, to be tested in 2023 and designed for low investment cost and dynamic flexibility, to a conventional system. For a thorough evaluation six equations of state, one provided by an industry partner, as well as chemical exergies with and without excess values are compared. With 64.59%, the novel design has a 4.87% lower exergetic degree of efficiency. The difference can be attributed to the simplified design of the novel cycle, mainly to the use of an electrical preheater instead of an internal gas-gas heat exchanger and a recycle valve instead of a recycle compressor. However, an upcoming exergy economic analysis will show that the novel cycle is more economical overall, as its investment costs are lower.","PeriodicalId":50325,"journal":{"name":"International Journal of Exergy","volume":"26 1","pages":"0"},"PeriodicalIF":1.1000,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"International Journal of Exergy","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1504/ijex.2023.134607","RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"ENERGY & FUELS","Score":null,"Total":0}
引用次数: 0
Abstract
Green ammonia is a promising carbon-free energy vector and means to store hydrogen efficiently. Employing the software Aspen Plus®, this work presents an exergetic comparison of a novel small-scale power-to-ammonia system, to be tested in 2023 and designed for low investment cost and dynamic flexibility, to a conventional system. For a thorough evaluation six equations of state, one provided by an industry partner, as well as chemical exergies with and without excess values are compared. With 64.59%, the novel design has a 4.87% lower exergetic degree of efficiency. The difference can be attributed to the simplified design of the novel cycle, mainly to the use of an electrical preheater instead of an internal gas-gas heat exchanger and a recycle valve instead of a recycle compressor. However, an upcoming exergy economic analysis will show that the novel cycle is more economical overall, as its investment costs are lower.
期刊介绍:
IJEX is dedicated to providing an interdisciplinary platform for information and ideas in the field of exergy and thermodynamic optimisation. It publishes a wide range of original, high-quality research papers, and ancillary features, spanning activities from fundamental research to industrial applications. IJEX covers aspects of exergy analysis of engineering and non-engineering systems and processes in a large variety of disciplines, ranging from mechanical engineering to physics and chemical engineering to industrial ecology.
Topics covered include:
-Thermodynamic systems
-Energy-related applications
-Process optimisation
-Energy systems, policies, planning
-Exergy/environment modelling
-Exergetic life cycle assessment
-Industrial ecology
-Sectoral exergy utilisation
-Waste exergy emissions
-Second-law efficiency
-Thermo- and exergo-economics
-Exergy in sustainable development
-Criticisms of and problems with use of exergy
-Entropy generation minimisation
-Constructal theory and design