Demand-side decarbonization and electrification: EMF 35 JMIP study

Japan’s long-term strategy submitted to the United Nations Framework Convention on Climate Change emphasizes the importance of improving the electrification rates to reducing GHG emissions. Using the five models participating in Energy Modeling Forum 35 Japan Model Intercomparison project (JMIP), we focused on the demand-side decarbonization and analyzed the final energy composition required to achieve 80% reductions in GHGs by 2050 in Japan. The model results show that the electricity share in final energy use (electrification rate) needs to reach 37–66% in 2050 (26% in 2010) to achieve the emissions reduction of 80%. The electrification rate increases mainly due to switching from fossil fuel end-use technologies (i.e. oil water heater, oil stove and combustion-engine vehicles) to electricity end-use technologies (i.e. heat pump water heater and electric vehicles). The electricity consumption in 2050 other than AIM/Hub ranged between 840 and 1260 TWh (AIM/Hub: 1950TWh), which is comparable to the level seen in the last 10 years (950–1035 TWh). The pace at which electrification rate must be increased is a challenge. The model results suggest to increase the electrification pace to 0.46–1.58%/yr from 2030 to 2050. Neither the past electrification pace (0.30%/year from 1990 to 2010) nor the outlook of the Ministry of Economy, Trade and Industry (0.15%/year from 2010 to 2030) is enough to reach the suggested electrification rates in 2050. Therefore, more concrete measures to accelerate dissemination of electricity end-use technologies across all sectors need to be established

Re-Defining System LCOE: Costs and Values of Power Sources

The mass introduction of variable renewable energies, including wind and solar photovoltaic, leads to additional costs caused by the intermittency. Many recent studies have addressed these “integration costs,” and proposed novel metrics that replace the traditional metric known as the levelized cost of electricity (LCOE). However, the policy relevance of those metrics remains unclear. In this study, the author investigates and re-defines the concept of system LCOE, referring to prior studies, and proposes concrete methods to estimate them. Average system LCOE allocates the integration cost to each power source, dividing that by the adjusted power output. Marginal system LCOE revises the concept of system LCOE and value-adjusted LCOE proposed by prior studies, to be clearer and more policy-relevant. These metrics are also applied to Japan’s power sector in 2050, suggesting the necessity of aiming for a “well-balanced energy mix” in future power systems with decarbonised power sources

EMF 35 JMIP study: preliminary results and implications for Japan’s climate change mitigation

The present study, Stanford Energy Modeling Forum (EMF) 35 Japan Model Intercomparison project (JMIP), employs five energy-economic and integrated assessment models to evaluate long-term climate change mitigation of Japan. Japan submitted its mid-century strategy last June to the Framework Convention on Climate Change, but the submitted strategy has not yet gone through modeling analysis. Moreover, along with other countries, Japan is expected to update its policy pledges in 2020. This study contributes modeling analysis to the ongoing policy debate. A preliminary analysis has been reported by Sugiyama et al. (2019, https://doi.org/10.1016/j.energy.2018.10.091) and this study further extends it. EMF 35 JMIP conducts a suite of sensitivity analysis on dimensions including emissions constraints, technology availability, and demand projections. The five participating models are: AIM/CGE, AIM/Enduse, DNE21, IEEJ, and TIMES-Japan. Four are bottom-up models, and one (AIM/CGE) is a computable general equilibrium model. We have harmonized GDP and population assumptions across models. The overall results confirm that mitigation strategies that work in other jurisdictions are also applicable in Japan, including energy efficiency, electricity decarbonization, and electrification. We also find that absent structural changes in the economy, heavy industry will be one of the hardest to decarbonize. Partly because of the challenges associated with industrial decarbonization, the marginal cost of abatement is higher than in the United States and comparable to that of Europe, as indicated by previous exercises of the EMF project. The challenge of industrial mitigation can be found in other Asian countries, particularly China and South Korea, and further investigation is warranted