1. Hydrogen as an export commodity – Capital expenditure and energy evaluation of hydrogen carriers.
- Author
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Hinkley, James T., Heenan, Alexander R., Low, Adrian C.S., and Watson, Matthew
- Subjects
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HYDROGEN as fuel , *CAPITAL investments , *LIQUID hydrogen , *CAPITAL costs , *LIQUID ammonia , *AMMONIA - Abstract
In this paper, we describe a case-study exploring the use of 600 MW of power from New Zealand's Manapouri Power Station to produce hydrogen for export via water electrolysis. Three H 2 carriers were considered: liquid H 2 , ammonia, and toluene hydrogenation/methylcyclohexane dehydrogenation. Processes were simulated in Aspen's HYSYS for each of the carriers to determine their associated energy and annualised capital expenditure costs. We found that the total capital investment for all carriers was surprisingly consistent, but with quite different splits between the electrolysis and carrier formation plants. Based on our analysis the energy availability for liquid H 2 ranged from 53.9 to 60.7% depending on the energy cost associated with cryogenic H 2 liquefaction. The energy availability for liquid ammonia was 37.5% after conversion back to H 2 , or 53.6% if the ammonia can be used directly as a fuel. For toluene/methylcyclohexane the energy availability was 41.2%. The total of the electricity and annualised capital costs per kg of H 2 ranged from NZ$5.63 to NZ$6.43 for liquid H 2 , NZ$6.24 to NZ$8.91 for ammonia and was NZ$7.86 for toluene/methylcyclohexane, using a net electricity cost of NZ$70/MWh. The cost of hydrogen (or energy in the case of direct use ammonia) was more strongly influenced by the efficiency of energy retention than on capital investment, as the electricity costs contributed approximately two thirds of total costs. In the long-term, liquid hydrogen looks to be the most versatile H 2 carrier, but significant infrastructure investment is required. • Capital costs of large-scale hydrogen carrier formation plants estimated. • Liquid hydrogen, ammonia and methylcyclohexane carrier systems compared. • Combined cost of electrolysis and carrier formation plants similar: from NZ$1.85 to $2.04 billion for a power envelope of 600 MW. • Energy efficiency of carrier system determines final cost of hydrogen energy. • Efficiency of ammonia comparable to liquid hydrogen, but only for direct use. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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