The role of hydrogen power generationin the low-carbon electricity grid
Hiroto SHIRAKI and Ai Fujiwara
The University of Shiga Prefecture

Introduction• Hydrogen is expected as a new option for a zero-carbon energy carrier.
• Although some existing studies1,2) investigate the impact of imported carbon-free hydrogen in the electricity
grid, the role of domestic hydrogen is not quantitatively analyzed.
• Research questions:• What will be the impact of hydrogen power generation on the generation mix in 2050?
• What will be the impact of hydrogen power generation on generation costs in 2050?
Methods• Multiregional optimal-generation planning model3)
Input: Electricity demand, fuelprices, capital costs, CO2 targets…

Hourly demandInterregional transmission line
Intraregional transmission line
Supply & demand node1 7 13 19
HourTop threedemand days
Summerholiday
Winterweekday

Main supply area of 10 major power companies
Chugoku
Hokuriku
Hokkaido
ShikokuTohokuChubu
Tokyo
KansaiKyushuOkinawa

Output: Generation mix,generation costs, carbon price…

Region: 10 regions
Year: 2050
Optimization: Recursive dynamic
Generators: Coal (boiler, IGCC, - w/CCS),

Oil (boiler), Gas (boiler, NGCC, -w/CCS),
Hydro (Conventional, pumped), Nuclear, Solar
PV, Wind (Onshore, offshore), Biomass,
Imported hydrogen

Power system stabilization measures:
Economic load dispatching control (EDC),
Load frequency control (LFC), Interregionaltransmission, Pumped hydro, Battery for longterm fluctuation (LFSB), Battery for short-term
fluctuation (SFSB), Curtailment, Domestichydrogen• Modeling hydrogen power generation

Two types of hydrogen power generations were newly incorporated.
1) Power plants using imported carbon-free hydrogen.
Capital costs, thermal efficiency: same as NGCC
Fuel price: 20JPY/Nm3 in 20504), CO2 emission intensity: 0 kg CO2/MJ
Maximum volume: 10 million tons in 20504)
2) Power plants using domestic hydrogen produced by electrolysis.
Modeled as an interseasonal and daily storage

Generation: Capital costs,
thermal efficiency: same as NGCC
Electrolysis: Capital costs, conversion
efficiency: 50,000 JPY/kW4), 70%4)• Scenario

Other power plants

Electricity

DemandFired power plant fordomestic hydrogen

HydrogenElectrolysis

Four scenarios: With/without imported hydrogen ✕ with/without domestic hydrogen
Nuclear & CCS: Assumed not to be available in 2050(a) Generation mix

Results• Imported hydrogen would reach its maximum
volume even in the low reduction target cases thanks toits cost competitiveness.
• Domestic hydrogen would increase VRE share about
10 percentage points in the high reduction target cases.(c) Total costs by generators• While fuel costs of “with imported hydrogen scenario”
were higher in 50-60% reduction cases, they became
lower in more than 70% reduction cases, due to theprice difference of imported biomass and hydrogen.
• Domestic hydrogen would reduce about 8 trillion(e) Capital costs
JPY of fuel costs by support to introduced VREs.
• Availability of imported hydrogen would have large
impacts on carbon prices in the 50-60% reduction
cases, but less in more than 70% reduction cases.

(b) VRE share(d) Fuel costs(f) Carbon prices↑ More than 4 mil. JPYDiscussion• Although imported hydrogen could be a cost-effective option, its impact on carbon price in the highreduction cases would be limited, due to its upper limit of importable volume.
• Domestic hydrogen would increase VRE share, and thus would improve energy security.
• Future tasks: considering interregional transmission of domestic hydrogen.

Asia-Pacific Integrated Model
http://www-iam.nies.go.jp/aim

1) Matsuo, Y. et al., Energy 165, 1200–1219 (2018), 2) Pambudi, N. A. et al., in Proceeding ICSEEA 2016, 66–69, 3) Shiraki, H. et al., J. Clean. Prod. 114, 81–94 (2016), 4) METI, New
Strategic Roadmap for Hydrogen and Fuel Cells (2019)

The 25th AIM International Workshop, November 18-19, 2019, Ohyama Memorial Hall, NIES, Tsukuba, Japan