Mid-century low emission scenarios in JapanKen Oshiro
Mizuho Information & Research InstituteThe 23rd AIM International Workshop
November 28, 2017. NIES, Tsukuba, Japan1

Recent updates related to AIM/Enduse [Japan]• NDC and Mid-century strategy in Japan• MILES: electrification report, completed this October• DDPP: national report on passenger transport
http://www.iddri.org/Publications/Rapports-and-briefing-papers/DDPPTR_JAP.pdf• CD-LINKS: National emission pathways assessment
based on emission budget• JMIP (Japan model inter-comparison project):• 6 energy models from Japanese institutes, including AIM/CGE
and AIM/Enduse [Japan]• National pathways corresponding to the 1.5 oC goal
• Net-zero emission scenarios in Japan by 2050
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AIM/Enduse [Japan]• Bottom-up of end-use sectors, hard-linked with energy supply sectors• Recursive dynamic model• Minimizing total system costs; capital, O&M, and emission costs
Primary Energy Supply

Parameters

OilCoalNatural Gas

NuclearHydroSolar

Wind

Geothermal

Biomass

Ocean

CO2 priceResults
GHG emissions

Energy Conversion Technologies
Energy prices

Electricity dispatch module

Energy conversion modules
 Oil refinery Gas processing Coal upgrading

Emission factors

 Heat generation
 Hydrogengeneration

Carbonsequestration

Demand load curve
Technical/economic
characteristics(Energy efficiency,Capital/O&M costs,Lifetime, etc.)

Energy/ClimatePolicies
Energy service
demandSectoral energy
supply/demand

Final Energy Consumption
Electricity

Oil

CoalGasHeat Renewables Hydrogen
Share oftechnologies

End-use Technologies
Industry

Transport

Residential/Commercial

 Iron & Steel Paper & Pulp
 Petrochemical Cement Machinery, etc.

(Passenger, Freight)
 Vehicles
 Train Maritime
 Aviation

 Space heating / cooling Water heating Cooking Lighting
 Appliances

Non-energy Industrial processes, Agriculture, Waste, etc.

Additional totalsystem costs3

National zero-emission pathway by 2050 in Japan• According to the previous studies on global 1.5oC pathways, CO2emissions needs to be net-zero around 2050 globally (Rogelj et al. (2015)).
• Assessing national net-zero emission pathways by 2050 using
AIM/Enduse [Japan], mainly focusing on:• difference of energy system transformation with the 2oC scenario(80% reduction by 2050)• the role of technologies, such as negative emission and nuclear• BECCS is added to the technology options in AIM/Enduse[Japan]• Paper published by Carbon Management Special Issue
Oshiro, K., Kainuma, M., & Masui, T. (2017). Transformation of Japan’s energy system toattain net-zero emission by 2050. Carbon management, (in press)

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Results: net-zero emission pathways in Japan• BECCS is required in zero-emission. 80% reduction is achievable
without BECCS• Phase-out of nuclear power would not compromise zero-emission• If following the NDC, drastic emission reduction is required after 2030
• Zero emission pathway results steep rise in CO2 price, more than 2,000
US$/t-CO2 in 2050
CO2 emissions, energy
CO2 price (US$/t-CO2)
EmissionconstraintTechnology availability
Fullw/oBECCS

Nuclearphase-out

Ref0

INDC-2deg

520

860

570

INDC-1.5deg

2,490

-

3,150

1.5deg

2,200

-

2,640

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Sectoral strategies to zero emission• Power sector needs to be largely transformed, including net-negative.
• Difference between net-zero and 80% reduction is moderate in thebuildings and industry sector.
• Buildings sector needs to be almost decarbonized even in 80% reduction.
Sectoral direct CO2 emissions

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Energy system transformation in power sector• Dependence on VREs, such as solar and wind, as well as BECCS.
• Given phase-out of nuclear, challenges to integrate VREs areexacerbated.
Electricity generation

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Energy system transformation in energy demand sectors• Buildings sector: completely electrified by 2050 even in the 80% reduction• Transport sector: switch to BEV and FCEV
Final energy demand by sources in the buildings and transportation sectors

8Discussion and conclusion• In Japan, net-zero emissions by 2050 requires drasticenergy system transformation, especially in power andtransport sector.
• Buildings sector needs to be decarbonized even in the 80%
reduction scenario by large-scale electrification.
• Achieving net-zero emissions by 2050 would require
substantial challenges, depending on only technologicaloptions.
As future works, assessing contribution of social andbehavioral change would be effective.
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