白木 裕斗 (シラキ ヒロト)

SHIRAKI Hiroto

写真a

職名

講師

研究分野・キーワード

エネルギーシステム学,環境システム学

ホームページ

http://www.ses.usp.ac.jp/shiraki/

出身大学院 【 表示 / 非表示

  • 東京大学  新領域創成科学研究科  環境システム学専攻  修士課程  2011年03月

  • 東京大学  新領域創成科学研究科  環境システム学専攻  博士課程  2014年03月

取得学位 【 表示 / 非表示

  • 博士(環境学)  東京大学  2014年03月

  • 修士(環境学)  東京大学  2011年03月

学内職務経歴 【 表示 / 非表示

  • 滋賀県立大学  環境科学部  環境政策・計画学科  講師   2019年04月 ~ 現在

  • 滋賀県立大学  環境科学部  環境政策・計画学科  助教   2016年10月 ~ 2019年03月

学外略歴 【 表示 / 非表示

  • 国立環境研究所  社会環境システム研究センター  特別研究員   2014年04月 ~ 2016年09月

  • 国立環境研究所  社会環境システム研究センター  客員研究員   2019年04月 ~ 現在

研究分野(科研費分類) 【 表示 / 非表示

  • エネルギー学

  • 環境政策・環境社会システム

 

論文 【 表示 / 非表示

  • The role of renewables in the Japanese power sector: implications from the EMF35 JMIP

    Shiraki H., Sugiyama M., Matsuo Y., Komiyama R., Fujimori S., Kato E., Oshiro K., Silva D.H.

    Sustainability Science  Sustainability Science    2021年01月

    10.1007/s11625-021-00917-y  共著  

    [概要]

    © 2021, The Author(s). The Japanese power system has unique characteristics with regard to variable renewable energies (VREs), such as higher costs, lower potentials, and less flexibility with the grid connection compared to other major greenhouse-gas-emitting countries. We analyzed the role of renewable energies (REs) in the future Japanese power sector using the results from the model intercomparison project Energy Modeling Forum (EMF) 35 Japan Model Intercomparison Project (JMIP) using varying emission reduction targets and key technological conditions across scenarios. We considered the uncertainties for future capital costs of solar photovoltaics, wind turbines, and batteries in addition to the availability of nuclear and carbon dioxide capture and storage. The results show that REs supply more than 40% of electricity in most of the technology sensitivity scenarios (median 51.0%) when assuming an 80% emission reduction in 2050. The results (excluding scenarios that assume the continuous growth of nuclear power and/or the abundant availability of domestic biomass and carbon-free hydrogen) show that the median VRE shares reach 52.2% in 2050 in the 80% emission reduction scenario. On the contrary, the availability of newly constructed nuclear power, affordable biomass, and carbon-free hydrogen can reduce dependence on VREs to less than 20%. The policy costs were much more sensitive to the capital costs and resource potential of VREs than the battery cost uncertainties. Specifically, while the doubled capital costs of VRE resulted in a 13.0% (inter-model median) increase in the policy cost, the halved capital costs of VREs reduced 8.7% (inter-model median) of the total policy cost. These results imply that lowering the capital costs of VREs would be effective in achieving a long-term emission reduction target considering the current high Japanese VRE costs.

  • EMF 35 JMIP study for Japan’s long-term climate and energy policy: scenario designs and key findings

    Sugiyama M., Fujimori S., Wada K., Oshiro K., Kato E., Komiyama R., Silva Herran D., Matsuo Y., Shiraki H., Ju Y.

    Sustainability Science  Sustainability Science    2021年01月

    10.1007/s11625-021-00913-2  共著  

    [概要]

    © 2021, The Author(s). In June, 2019, Japan submitted its mid-century strategy to the United Nations Framework Convention on Climate Change and pledged 80% emissions cuts by 2050. The strategy has not gone through a systematic analysis, however. The present study, Stanford Energy Modeling Forum (EMF) 35 Japan Model Intercomparison project (JMIP), employs five energy-economic and integrated assessment models to evaluate the nationally determined contribution and mid-century strategy of Japan. EMF 35 JMIP conducts a suite of sensitivity analyses on dimensions including emissions constraints, technology availability, and demand projections. The results confirm that Japan needs to deploy all of its mitigation strategies at a substantial scale, including energy efficiency, electricity decarbonization, and end-use electrification. Moreover, they suggest that with the absence of structural changes in the economy, heavy industries will be one of the hardest to decarbonize. Partitioning of the sum of squares based on a two-way analysis of variance (ANOVA) reconfirms that mitigation strategies, such as energy efficiency and electrification, are fairly robust across models and scenarios, but that the cost metrics are uncertain. There is a wide gap of policy strength and breadth between the current policy instruments and those suggested by the models. Japan should strengthen its climate action in all aspects of society and economy to achieve its long-term target.

  • 住宅に対する住民評価の要因分析 - 省エネ性の影響 -

    藤本穂乃佳,白木裕斗,村上一真

     土木学会論文集G(環境)  77 (5)   I_331 ~ I_339  2021年

    共著  共同(主担当)

  • Back to the basic: toward improvement of technoeconomic representation in integrated assessment models

    Shiraki H., Sugiyama M.

    Climatic Change  Climatic Change  162 (1)   13 ~ 24  2020年09月

    10.1007/s10584-020-02731-4  共著  

    [概要]

    © 2020, Springer Nature B.V. With the shift of climate debate from understanding to actions, the use of integrated assessment models (IAMs) is gradually expanding. Since IAMs produce least-cost pathways, technoeconomic parameters constitute one of the basic parameters. Traditionally, IAMs dealt with technologies with slowly-changing, relatively homogeneous manner. Since technologies are rapidly evolving, and the pattern of technological development is regionally heterogeneous, the IAM community must embrace a new strategy to treat their underlying technoeconomic parameters. Here we illustrate such challenges by reviewing the treatment and performance of IAMs with respect to some of the rapidly changing technologies (e.g., solar, wind, and batteries). Our review shows that IAMs have difficulty in updating the cost of the rapidly changing technologies. We then articulate a new strategy, drawing upon the lesson from the current model intercomparison projects and climate sciences. We argue that a loose network of modeling groups across the globe should create a database of technological parameters in a standardized format and standard evaluation tool, perhaps to be facilitated by the IAM Consortium. Such a framework would contribute to the review of the progress toward the Paris Agreement goals.

  • Factors affecting CO<inf>2</inf> emissions from private automobiles in Japan: The impact of vehicle occupancy

    Shiraki H., Matsumoto K., Shigetomi Y., Ehara T., Ochi Y., Ogawa Y.

    Applied Energy  Applied Energy  259    2020年02月

    10.1016/j.apenergy.2019.114196  共著  

    [概要]

    © 2019 Elsevier Ltd The road transport sector accounted for 18.8% of global CO2 emissions in 2016. Regional efforts are indispensable for reducing automobile emissions, especially considering the diversity in regional transportation systems. Existing studies of automobile emissions have focused on nationwide transportation systems or differences in city size without considering regionality and long-term changes in vehicle occupancy. In this study, we decomposed national and regional automobile emissions in Japan between 1990 and 2015 by the Logarithmic Mean Divisia Index method. Statistical data that took vehicle occupancy into account were used. Results showed that nationwide vehicle occupancy increased (due to increased vehicle size and vehicle ownership), which increased emissions by 15.2% compared to 1990 levels. In highly populated regions, fuel efficiency decreased earlier than other regions thanks to the strengthening of ordinances regarding air pollution. In Western Japan, which includes less-populated prefectures, the rising popularity of mini-vehicles resulted in increased vehicle ownership and a decrease in occupancy but also led to improvements in fuel economy. To reduce automobile CO2 emissions, it will be essential to improve fuel efficiency and to increase vehicle occupancy through mechanisms, such as ridesharing and vehicle right sizing.

  • 企業における電気自動車の導入実態と導入意思の要因分析

    白木裕斗, 佐藤真, 村上一真

     土木学会論文集G(環境)  76 (5)   I_187 ~ I_195  2020年

    共著  共同(主担当)

  • Energy transformation cost for the Japanese mid-century strategy

    Fujimori S., Oshiro K., Shiraki H., Hasegawa T.

    Nature Communications  Nature Communications  10 (1)    2019年12月

    10.1038/s41467-019-12730-4  共著  

    [概要]

    © 2019, The Author(s). The costs of climate change mitigation policy are one of the main concerns in decarbonizing the economy. The macroeconomic and sectoral implications of policy interventions are typically estimated by economic models, which tend be higher than the additional energy system costs projected by energy system models. Here, we show the extent to which policy costs can be lower than those from conventional economic models by integrating an energy system and an economic model, applying Japan’s mid-century climate mitigation target. The GDP losses estimated with the integrated model were significantly lower than those in the conventional economic model by more than 50% in 2050. The representation of industry and service sector energy consumption is the main factor causing these differences. Our findings suggest that this type of integrated approach would contribute new insights by providing improved estimates of GDP losses, which can be critical information for setting national climate policies.

  • Japan's long-term climate mitigation policy: Multi-model assessment and sectoral challenges

    Sugiyama M., Fujimori S., Wada K., Endo S., Fujii Y., Komiyama R., Kato E., Kurosawa A., Matsuo Y., Oshiro K., Sano F., Shiraki H.

    Energy  Energy   1120 ~ 1131  2019年01月

    10.1016/j.energy.2018.10.091  共著  

    [概要]

    © 2018 The Authors Japan is the sixth largest greenhouse gas emitter in 2016 and plays an important role to attain the long-term climate goals of the Paris Agreement. One of the key policy issues in Japan's energy and environmental policy arena is the energy system transition to achieve 80% emissions reduction in 2050, a current policy goal set in 2016. To contribute to the ongoing policy debate, this paper focuses on energy-related CO 2 emissions and analyzes such decarbonization scenarios that are consistent with the government goals. We employ six energy-economic and integrated assessment models to reveal decarbonization challenges in the energy system. The modeling results show that Japan's mitigation scenarios are characterized by high marginal costs of abatement. They also suggest that the industrial sector is likely to have a large final energy share and significant residual emissions under the 80% reduction scenario, though it is generally thought that the transport sector would have large decarbonization challenges. The present findings imply that not only energy policy but also industrial policy may be relevant to the long-term environmental target. Given the high marginal costs exceeding those of negative emissions technologies that could place a cost ceiling, further model development would be crucial.

  • Addressing Key Drivers of Regional CO2 Emissions of the Manufacturing Industry in Japan

    Ken’ichi Matsumoto, Yosuke Shigetomi, Hiroto Shiraki, Yuki Ochi, Yuki Ogawa, Tomoki Ehara

     The Energy Journal  40 (1)    2019年

    共著  共同(副担当)

  • Driving forces underlying sub-national carbon dioxide emissions within the household sector and implications for the Paris Agreement targets in Japan

    Shigetomi Y., Matsumoto K., Ogawa Y., Shiraki H., Yamamoto Y., Ochi Y., Ehara T.

    Applied Energy  Applied Energy  228   2321 ~ 2332  2018年10月

    10.1016/j.apenergy.2018.07.057  共著  

    [概要]

    © 2018 Elsevier Ltd This study investigated insights into reducing energy-related CO2 emissions in households by examining individual socio-economic drivers at a sub-national level. Specifically, the logarithmic mean Divisia index technique was used to decompose CO2 emission trends into six drivers in all 47 prefectures of Japan during the period from 1990 to 2015. Drivers included the change in the number of households (household effect), distribution of households (distribution effect), household size (size effect), per-capita household energy consumption (consumption effect), household energy choice (choice effect), and sectoral CO2 emission intensity (intensity effect). The results showed that, in contrast to size and the distribution effects, the number of households had a positive, significant effect on CO2 emissions, indicating that recent demographic trends are responsible for the increase in CO2 emissions observed in most of the prefectures during the study period. With regard to effects related to consumption and choice, CO2 emissions due to changes in lifestyle dropped in only seven prefectures and reductions due to changes in sectoral energy choice were seen in only two prefectures in 2015. The intensity effect boosted the emissions of these prefectures the most in 2015 because of the shutdown of nuclear power plants due to the Great East Japan Earthquake. Further, we identified those prefectures that needed to reduce their per-capita energy consumption level in order to attain the reduction targets for household CO2 emissions in 2030 from 2015, given projected changes in demographic trends and recent and projected emission intensities. In order to achieve reductions in total CO2 emissions in line with the Paris Agreement, it is important to prioritize national and local policy interventions for the transfer of new household energy technologies, upgrade household appliances, and encourage people to limit energy consumption in light of the differences in these key drivers in each prefecture.

全件表示 >>

著書 【 表示 / 非表示

  • 脱炭素社会のエネルギーを考える <高校生・高専生向けテキスト> 

    柳下正治(編),荒井眞一,磐田朋子, 木村浩,白木裕斗,西岡秀三,松橋啓介

    一般社団法人 環境政策対話研究所  2021年10月

    教科書  分担執筆

総説・解説記事 【 表示 / 非表示

会議での講演 【 表示 / 非表示

  • Perceived Feasibility of Japan’s decarbonization transition: Expert Perspectives

    14th IAMC Annual Meeting 2021  2021年11月

  • Assessment of generation mix in 2030 using high resolution power dispatch model

    The 27th AIM International Workshop  2021年09月

  • 住宅に対する住民評価の要因分析 - 省エネ性の影響 -

    土木学会 第29回地球環境シンポジウム  2021年09月

  • 電力需要の不確実性を考慮した電力システム分析

    第40回エネルギー・資源学会研究発表会  2021年08月

  • 長期低排出発展戦略下の電力システムにおける再生可能エネルギーの役割:EMF35 JMIPからの含意

    再生可能エネルギー・モデリングに関する研究ワークショップ  2020年11月

  • 企業における電気自動車の導入実態と導入意思の要因分析

    第28回地球環境シンポジウム  2020年09月

  • Preliminary assessment of generation mix in 2050 using power dispatch model with long-term chronological data

    The 26th AIM International Workshop  2020年09月

  • The role of hydrogen power generation in the low-carbon electricity grid

    The 25th AIM International Workshop  2019年11月

  • Estimation of Flexibility Resources for Power System Stabilization under a Long-term Low Carbon Scenario

    24th AIM International Workshop  2018年11月

  • Integrated Assessment and Rapid Technological Changes - toward shorter IPCC cycle

    International Energy Workshop  2018年06月

全件表示 >>

受賞学術賞 【 表示 / 非表示

  • 学生発表賞

       国内学会・会議・シンポジウム等の賞  エネルギー・資源学会  共同(主担当)  2014年06月

  • 専攻長賞

       その他の賞  東京大学大学院新領域創成科学研究科 環境システム学専攻  単独  2011年03月

  • Outstanding Paper Award

       国際学会・会議・シンポジウム等の賞  第8回分離技術国際会議  共同(主担当)  2008年10月

 

競争的資金(科学研究費補助金・振興調整費・JSPS等) 【 表示 / 非表示

  • 世界全域を対象とした技術・経済・社会的な実現可能性を考慮した脱炭素社会への道筋に関する研究

     環境研究総合推進費   2021年04月 ~ 2024年03月

  • 将来の不確実性を考慮した頑健な脱炭素電力システムシナリオ分析

     科学研究費補助金 若手研究   2021年04月 ~ 2024年03月

 
 

国・地方公共団体等における審議会・委員会等の委員 【 表示 / 非表示

  • 京都市  環境審議会 地球温暖化対策推進委員会  委員   2021年04月 ~ 現在

  • 京都市  環境審議会  委員   2021年04月 ~ 現在

  • 環境政策対話研究所  脱炭素社会を拓く高校生・高専生向けプログラムの開発・普及研究会  委員   2020年07月 ~ 現在

  • 長浜市  地球温暖化対策実行計画策定委員会  委員長   2020年04月 ~ 2021年03月

学会等における役職 【 表示 / 非表示

  • エネルギー・資源学会  ワークショップ幹事   2014年04月 ~ 現在

  • エネルギー・資源学会  代議員   2014年04月 ~ 現在

学外の社会活動 【 表示 / 非表示

  • FY2021 Asia Fieldwork   2022年01月

  • A selection of 2021's highlighted research - Climate   2022年01月

  • 2021年度高校生ノーザンカンファレンス   2021年10月 ~ 2021年12月

  • 2021年度次世代エネルギーワークショップ名古屋   2021年07月 ~ 2021年08月

  • 日本版気候若者会議   2021年06月