Theoretical performance analysis of hydrate-based heat engine system suitable for low-temperature driven power generation

Yugo Ohfuka, Ryo Ohmura

Research output: Contribution to journalArticle

7 Citations (Scopus)

Abstract

We analyzed a heat engine using clathrate hydrate as its working media and evaluate the performance of this system operated with high and low temperature reservoirs of 295 K and 280 K "OTEC (Ocean Thermal Energy Conversion)" may be a prospective example of the technologies utilizing the small-temperature difference for power generation. This heat engine generates mechanical power through the cycle of following processes: hydrate formation at low temperature, pumping of hydrate, isobaric heating of hydrate, hydrate dissociation and adiabatic expansions of dissociated gas and water. The thermal efficiency for Kr, Xe, CH3F, CH2F2 and CH4 hydrates were evaluated. The analysis showed the dominant properties were the enthalpy difference of the working media in the adiabatic expansions, the pressure range in the whole process and the dissociation heat. The thermal efficiency is 2.20% for Kr hydrate and 2.89% for Xe hydrate. While these are slightly inferior to those of Rankine cycle: 3.30% for C2H3F3 and 3.34% for C3H8, Kr and Xe hydrates are greatly favorable in terms of environmental friendliness. These results indicate the prospects of the hydrate heat engine for the power generation utilizing a small temperature difference as an environment-friendly technology.

Original languageEnglish
Pages (from-to)27-33
Number of pages7
JournalEnergy
Volume101
DOIs
Publication statusPublished - 2016 Apr 15

Fingerprint

Heat engines
Hydrates
Power generation
Temperature
Ocean thermal energy conversion
Rankine cycle
Enthalpy
Heating

Keywords

  • Clathrate hydrates
  • Heat engine
  • Ocean thermal energy conversion
  • Renewable energy

ASJC Scopus subject areas

  • Energy(all)
  • Pollution

Cite this

Theoretical performance analysis of hydrate-based heat engine system suitable for low-temperature driven power generation. / Ohfuka, Yugo; Ohmura, Ryo.

In: Energy, Vol. 101, 15.04.2016, p. 27-33.

Research output: Contribution to journalArticle

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