Language：English   Publishing type：Research paper (scientific journal)  

The Impact of Renewable Energy Generation on the Spot Market Price in Germany: Ex-Post Analysis using Boosting Method
This study combines regression analysis with machine learning analysis to study the merit order effect of renewable energy focusing on German market, the largest market in Europe with high renewable energy penetration. The results show that electricity from wind and solar sources reduced the spot market price by 9.64 (sic)/MWh on average during the period from 2010 to 2017. Wind had a relatively stable impact across the day, ranging from 5.88 (sic)/MWh to 8.04 (sic)/MWh, while the solar energy impact varied greatly across different hours, ranging from 0.24 (sic)/MWh to 11.78 (sic)/MWh and having a stronger impact than wind during peak hours. The results also show characteristics of the interactions between renewable energy and spot market prices, including the slightly diminishing merit order effect of renewable energy at high generation volumes. Finally, a scenario-based analysis illustrates how different proportions of wind and solar energies affect the spot market price.

DOI： 10.5547/01956574.41.si1.akee

Language：English   Publishing type：Research paper (scientific journal)  

Drivers of green bond market growth The importance of Nationally Determined Contributions to the Paris Agreement and implications for sustainability
Green bonds are increasingly being applied to finance emissions reductions, sustainable development, and other cleaner production investments conducive to reaching the 2 °C temperature target of the Paris Agreement. As their markets are relatively nascent, there is a gap in the empirical literature on the drivers of green bond market growth. To assess the impact that capital market growth drivers and Nationally Determined Contributions to the Paris Agreement have on green bond issuance volumes as indicators of market growth, this study employed a structural equation model using a panel dataset of over $300 billion in green bonds issued in 49 countries between 2007 and 2017. This is the first econometric study to demonstrate unique drivers of green bond market growth in addition to factors that similarly affect conventional bond market growth. This is also the first study to construct a normalized index of Nationally Determined Contributions robustness scores to measure their impacts on green bond market growth. Macroeconomic latent factors exerted three times the total influence exerted by institutional latent factors. Institutional effects are positive and indirect, while OECD membership impacts were small and statistically insignificant. Nationally Determined Contributions scores exerted the largest positive and statistically significant impacts among observed variables. These results suggest that Nationally Determined Contributions and other macroeconomic and institutional factors are driving growing green bond issuances that will finance climate and sustainability investments through the future. They also highlight the need for broader examinations of the determinants of green bond issuances as investment vehicles for sustainable outcomes.

DOI： 10.1016/j.jclepro.2019.118643

Language：English   Publishing type：Research paper (scientific journal)  

Green bonds for the Paris agreement and sustainable development goals
The Paris Agreement under the United Nations Framework Convention on Climate Change and the Sustainable Development Goals (SDGs) of the United Nations Development Programme both entail substantial global investments through cost-efficient, long-term financing. Noted for their risk-alleviating features and appeal to institutional and socially responsible investors, green bonds are gaining prominence in climate change and sustainable development finance frameworks. This study is the first to thoroughly examine publicly reported green bond proceeds allocations from 53 organizations to projects and assets throughout 96 countries from 2008 to 2017. Green bond markets are growing rapidly, and yearly proceeds allocation trends reveal increasing disbursements to renewable energy, clean water, low-carbon transportation, and other Paris Agreement and SDG-related investment categories. Circle plot analysis reveals unique allocation trends to specific green sectors at both regional and national levels. International finance institutions allocated the largest share of proceeds by both frequency and volume, and the projects and assets financed with green bonds in this study sample are associated with over 108 million tonnes of carbon dioxide equivalent (tCO₂e) in greenhouse gas emissions reductions and over 1500 gigawatts in renewable energy capacity. The study concludes with suggestions for improving green bond post-issuance reporting and provides insights for future green bond applications in expanding Paris and SDG agendas.

DOI： 10.1088/1748-9326/ab1118

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.3934/GF.2019.2.139

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.3390/su11051370

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.enpol.2018.08.055

Language：English  

Language：English  

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.jclepro.2017.12.154

Language：English   Publishing type：Research paper (scientific journal)  

Determinants of foreign direct investment in wind energy in developing countries
The renewable energy industry is one of the fastest growing industries attracting a great amount of foreign direct investment, being one of the top 5 industries in 2015 in terms of the amount of investment allocated. However, the allocation of foreign direct investment in the sector greatly varies between developing countries. Preceding studies have tried to explain the location determinants of foreign direct investment mainly by looking at the effects of institutional and macroeconomic factors. The renewable energy sector has been supported by various economic, regulatory, and political support policies. Considering the importance of these support policies, the paper analyses their effects on foreign direct investment as location determinants in comparison with that of the widely accepted determinants (institutional and macroeconomic determinants), focusing on wind energy in developing countries. The results show that renewable energy support policies have equivalent or greater effect compared to the widely accepted determinants such as corruption level, price stability, access to finance, and GDP growth. The paper demonstrates the importance of analysing determinants of foreign direct investment focusing on a specific sector rather than looking at overall foreign direct investment. The paper also provides important policy implications including the need to improve the regulatory aspect of renewable energy sector such as access to grid infrastructure in order to attract foreign direct investment into the sector.

DOI： 10.1016/j.jclepro.2017.05.106

Language：English   Publishing type：Research paper (bulletin of university, research institution)  

Language：English   Publishing type：Research paper (scientific journal)  

Renewable Energy in Pacific Small Island Developing States the role of international aid and the enabling environment from donor's perspectives
Dependency on fossil fuels is an issue for numerous countries, and in particular, it is an acutely challenging problem for Pacific Small Island Developing States. For the utilization of Renewable Energy in Pacific Small Island Developing States, donor agencies and international organizations play major roles in funding. This study introduces the nature of the past renewable energy projects in Pacific Small Island Developing States and, in the process, clarifies the contribution of international aid to renewable energy deployment. Thereafter, the paper identifies the most important factors related to enhancing an enabling environment for the introduction of Renewable Energy in Pacific Small Island Developing States and the relative importance of these factors with a special focus on donors’ perspectives. The paper clarifies that approximately 1.5 billion USD (2011) was received by Pacific Small Island Developing States over the 44 years from 1970 to 2014 as funding for renewable energy projects that included funding for hardware, and the amount of aid allocated for renewable energy in the region greatly varies between countries. The paper also identifies the important factors that can enhance an enabling environment for the introduction of renewable energy and the relative importance of these factors. Some of the highlighted implications that can be made from the findings of the research are: (1) high renewable energy targets need to be supported by well-structured action plans; (2) there is a need for an effective regulatory body responsible for renewable energy; and (3) the financial aspects of utilities are of higher importance than technological aspects of utilities.

DOI： 10.1016/j.jclepro.2016.05.011

Language：English   Publishing type：Research paper (bulletin of university, research institution)  

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1088/1755-1315/505/1/012044

Publisher：Journal of Environmental Management  

As global concern over the negative impacts of global warming, primarily caused by using passenger vehicles (PVs), the transition to hydrogen fuel cell vehicles (HFCVs) is an essential alternative for reducing greenhouse (GHG) emissions. This research employs a bottom-up approach to analyze road vehicle fleet's GHG emissions. We calculated GHG emissions from PVs in 15 Group of Twenty (G20) countries based on four scenarios adopting the global HFCVs from 2024 to 2050. This paper introduces business-as-usual (BaU), moderate, aggressive, and non-HFCVs scenario. The results show that the aggressive scenario has the highest sales, estimated between 62,000 and 29.48 million vehicles by 2050, with global hydrogen market penetration rates 48.48%. Building on countries' respective national strategies, the findings highlight China and India as the leading markets for hydrogen demand, with Germany and Japan also showing significant interest. The aggressive scenario further demonstrates that transitioning from internal combustion engine vehicles (ICEVs) to battery electric vehicles (BEVs), plug-in hybrid electric vehicles (PHEVs), and HFCVs can significantly reduce annual GHG emissions. Ultimately, this study finds that the transition to HFCVs could reduce emissions by up to 67.09% by 2050.

DOI： 10.1016/j.jenvman.2024.122660

Scopus

Publisher：Applied Energy  

Deploying negative emission technologies has become crucial for limiting the global temperature rise to approximately 1.5 °C above preindustrial levels. DAC technologies are being explored as one of the prospective options. These technologies have been thoroughly investigated as a potential project to capture CO2 emissions and provide purified air, natural gas, or fuel oil. An applied approach, on the other hand, was not taken into consideration while evaluating the influence that this technology has on emissions. For this reason, British Columbia provides a substantial chance to examine emissions that were produced after the DAC actions were put into place in 2015. In this study, the difference-in-differences methodology is employed for the very first time to compare the emissions that are produced by the transport sectors in British Columbia with those emitted by other provinces in Canada. The role that GDP and population play in the release of emissions is also taken into consideration in this paper. Based on the research results, it can be observed that the implementation of DAC initiatives has yielded notable effects. Evidence shows that the DAC effort has led to an average reduction of 0.08 in logarithmic CO2 emissions in the transport sector. By accounting for GDP and population, the empirical results indicate that DAC technology reduced CO2 emissions in British Columbia compared to provinces without DAC facilities. DAC initiatives are expected to become increasingly prevalent between the mid-2030s and 2040s. Overall policy implications suggest that there is a need for DAC technologies to collaborate with alternative mitigation technologies, or alternative technologies should collaborate with DAC technologies that are more efficient to achieve the targeted goals in a short time.

DOI： 10.1016/j.apenergy.2024.123112

Scopus

Publishing type：Research paper (scientific journal)   Publisher：Wiley  

Abstract

Japan has been at the forefront of global efforts to accelerate climate change mitigation. Japanese firms have led in the development of decarbonization technologies and have positively disclosed climate change‐related information based on the Task Force on Climate‐related Financial Disclosures recommendations to address climate change. We explore the relationship between corporate climate change mitigation actions and the cost of capital for 2100 Japanese listed companies from 2017 to 2021. The results reveal that a higher carbon intensity correlates with an increased cost of equity, debt, and weighted average cost of capital. Interestingly, although climate‐related information disclosure is associated with an increased cost of debt, it concurrently lowers the cost of equity and overall capital. This research recommends strategic approaches for firms to reduce their costs of capital while proactively combating climate change, highlighting the divergent responses of equity and bond markets to decarbonization initiatives.

DOI： 10.1002/csr.2853

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Publisher：International Journal of Hydrogen Energy  

This paper precisely estimates the looming demand for hydrogen within the transportation sector, spanning 14 pivotal G20 nations from 2022 to 2050, anchored in the global vehicle hydrogen market penetration rate. Employing a robust techno-economic modeling methodology and leveraging Geographic Information System (GIS) for enriched visualization, it unveils distinct environmental dividends across three thoughtfully devised scenarios: Business-as-Usual, Moderate, and Aggressive. Findings herald India and China as pinnacles of hydrogen demand, with South Korea and Japan tailing closely. The study forecasts the energy consumption for solar hydrogen production in G20 countries to oscillate between 3.02 and 2.89 million GWh in 2022, while production costs are anticipated to range from $8.47/kg to $10.01/kg. In an assertive scenario, the paper illuminates a pathway towards achieving a significant CO2 reduction, unmasking environmental savings of up to a staggering 48%, equivalent to 1.5 million mtCO2, by 2050.

DOI： 10.1016/j.ijhydene.2023.12.246

Scopus

Language：Others   Publishing type：Research paper (scientific journal)   Publisher：MDPI AG  

This study investigates the impact of environmental concerns, concerns about potential accidents, and the perceived advantages of fully autonomous vehicles on individuals’ willingness to buy and the perceived value of these vehicles. Our research, conducted through a comprehensive survey with over 180,000 respondents in Japan and analyzed using structural equation modeling, reveals a nuanced disparity between willingness to buy and perceived value. We find that individuals concerned with the conservation of the natural environment are more likely to purchase fully autonomous vehicles due to their broader interest in societal issues and belief in the potential of new technologies like fully autonomous vehicles as solutions. However, these individuals attribute a lower perceived value to these vehicles, mainly because their adoption does not directly contribute to the conservation of the natural environment. Additionally, our results show that those recognizing the potential advantages of fully autonomous vehicle technology have a higher willingness to buy and perceived value, while those with apprehensions about the technology are less likely to purchase and attribute a lower perceived value to these vehicles. This study offers vital insights for policy and planning, highlighting the complex interplay of factors influencing the willingness to buy and perceived value of fully autonomous vehicles, critical for strategizing their adoption.

DOI： 10.3390/app14010410

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Language：Others   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

DOI： 10.1016/j.rser.2023.114037

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Repository Public URL： https://hdl.handle.net/2324/7182009

Language：Others   Publishing type：Research paper (scientific journal)  

DOI： 10.3389/frsus.2023.1130622

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Repository Public URL： https://hdl.handle.net/2324/7182008

Language：English   Publishing type：Research paper (scientific journal)   Publisher：SPRINGER  

DOI： 10.1007/s10894-023-00361-z

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Repository Public URL： https://hdl.handle.net/2324/7182007

Language：English  

article number 16

CiNii Research

Language：English   Publishing type：Research paper (scientific journal)   Publisher：WILEY  

Although the consideration of financial materiality is important for securing shareholders' interests, the degree of financial materiality that is considered for existing sustainability ratings is still questionable. In this study, we hand-mapped the financial materiality of environmental information based on Sustainability Accounting Standards Board (SASB) industry-specific accounting metrics to reassess environmental performance. Based on the SASB-based environmental score, we tested whether investors price environmental risk. The results show significant pricing anomalies related to environmental risk. Companies with lower SASB-based environmental scores experience higher environmental risk. Additionally, a premium in the cross-section of stock returns compensates for this risk. Our findings suggest that integrating financial materiality based on the SASB could be an effective way to capture corporate environmental risk.

DOI： 10.1002/csr.2524

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Repository Public URL： https://hdl.handle.net/2324/7182006

Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER SCI LTD  

For Japan to achieve its targets for carbon neutrality and reduction of carbon dioxide (CO_2) emissions, decarbonization of road transport is essential. Japan regards next-generation vehicles, including hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), battery electric vehicles (BEVs), and fuel cell vehicles, as a key means of reducing carbon emissions from road transport. Four scenarios were proposed to predict the potential carbon emissions reduction of passenger car use in 2030: baseline, business-as-usual, government's target-based, and aggressive scenarios. Economic input–output life cycle assessment was used to evaluate potential CO_2 emissions, acidification, eutrophication, human toxicity, and photochemical oxidation associated with passenger cars. In this study, all environmental impacts were calculated using the multi-regional environmentally extended supply and use/input–output database by applying the CML 2001 impact assessment method. The findings indicate that PHEVs have the lowest CO_2 emissions per km traveled, followed by HEVs and BEVs. The prediction for carbon emissions from passenger cars shows that adopting electrified vehicles, such as HEVs, PHEVs, and BEVs could help decarbonize the passenger car sector. The population of vehicles, vehicle manufacturing, well-to-wheel cycle of fuel, and fuel economy will significantly contribute to CO_2 emissions. Finally, this study recommends policies to steer Japan into achieving its goal of carbon neutrality.

DOI： 10.1016/j.iatssr.2023.02.004

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Repository Public URL： https://hdl.handle.net/2324/7182005

Language：English  

Recently, concerns about ecosystem loss and the threat of disasters have emerged. Understanding people’s perception of the ecosystem’s value will lead to disaster adaptation through ecosystem conservation. We incorporated use and disaster attributes into a contingent valuation study to investigate Japanese peoples’ perceptions of the value of various ecosystems. We construct a concept representing ecosystems’ perceived disaster prevention and mitigation functions by investigating the effects of use status and disaster concerns on people’s preferences. Results revealed that almost all of the ecosystem’s disaster prevention and mitigation functions are not perceived by people. In some cases, people mistakenly avoid ecosystems that protect people from disasters. In conclusion, this concept and its findings facilitate an understanding of people’s perceptions of disaster prevention mitigation functions of ecosystems and promote the concrete practice of conserving ecosystems.

CiNii Research

CiNii Research

Language：English   Publishing type：Research paper (scientific journal)   Publisher：MDPI  

Recently, concerns about ecosystem loss and the threat of disasters have emerged. Understanding people's perception of the ecosystem's value will lead to disaster adaptation through ecosystem conservation. We incorporated use and disaster attributes into a contingent valuation study to investigate Japanese peoples' perceptions of the value of various ecosystems. We construct a concept representing ecosystems' perceived disaster prevention and mitigation functions by investigating the effects of use status and disaster concerns on people's preferences. Results revealed that almost all of the ecosystem's disaster prevention and mitigation functions are not perceived by people. In some cases, people mistakenly avoid ecosystems that protect people from disasters. In conclusion, this concept and its findings facilitate an understanding of people's perceptions of disaster prevention mitigation functions of ecosystems and promote the concrete practice of conserving ecosystems.

DOI： 10.3390/su15043154

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Repository Public URL： https://hdl.handle.net/2324/7182003

Language：Others   Publishing type：Research paper (scientific journal)  

The coronavirus (COVID-19) pandemic has affected society in immeasurable ways, including investment. As the pandemic has impacted society's values, it has proven to be a major turning point for environmental, social, and governance (ESG) investment. This investment approach, which evaluates a company's ESG ratings alongside traditional financial metrics, was already “coming off a banner year,” and its reach continues to expand. Although numerous studies have investigated the impact of ESG scores on financial returns and the trend in ESG investment strategies, only a limited number of studies have attempted to capture the key players in ESG investment. Therefore, to determine the most influential investors in the ESG investment field, the cumulative impacts are calculated based on the ESG scores of invested companies, the total market price of invested companies, and the investor history portfolio report. We perform an iteration of calculation to convey the impacts that the invested companies have on the ultimate investors, and we identify the major players in the field and differences in the trend by type of investor and country.

DOI： 10.3389/frsus.2022.909239

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Repository Public URL： https://hdl.handle.net/2324/7161197

Language：English   Publishing type：Research paper (scientific journal)   Publisher：SPRINGER JAPAN KK  

Weather conditions critically affect electricity demand. Recently, weather changes have also affected the electricity supply because renewable energy sources have been diffused. Some studies have revealed that weather conditions affect electricity supply or demand. However, few studies have revealed the integrated effects of weather changes on the electricity supply, demand, and market prices. This study aims to reveal the regional weather impact on the German electricity spot market based on combined hourly weather and electricity market data using structural equation modeling. Our results reveal that weather changes affect both demand and supply. First, the effect of weather on electricity supply differs in each state. Our estimation results show a more complex effect of an increase in solar radiation. Second, the electricity demand is also affected by weather conditions, particularly by temperature. Additionally, regional differences in weather conditions create a complex structure of electricity supply and demand. Our results indicate that extreme weather events in specific areas have a significant impact on the electricity market price.

DOI： 10.1007/s11625-022-01219-7

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Language：English  

The coronavirus (COVID-19) pandemic has affected society in immeasurable ways, including investment. As the pandemic has impacted society’s values, it has proven to be a major turning point for environmental, social, and governance (ESG) investment. This investment approach, which evaluates a company’s ESG ratings alongside traditional financial metrics, was already “coming off a banner year,” and its reach continues to expand. Although numerous studies have investigated the impact of ESG scores on financial returns and the trend in ESG investment strategies, only a limited number of studies have attempted to capture the key players in ESG investment. Therefore, to determine the most influential investors in the ESG investment field, the cumulative impacts are calculated based on the ESG scores of invested companies, the total market price of invested companies, and the investor history portfolio report. We perform an iteration of calculation to convey the impacts that the invested companies have on the ultimate investors, and we identify the major players in the field and differences in the trend by type of investor and country.

CiNii Research

Language：English   Publishing type：Research paper (scientific journal)   Publisher：ELSEVIER  

Reaching carbon neutrality would require the retirement of conventional power sources and substitution with renewable energy sources. Given that immediate substitution from conventional to renewable power sources is not feasible in the status quo, we investigate whether adding residential solar photovoltaic (PV) technology in addition to conventional power sources would reduce residential emissions. We use a large survey dataset of more than 300,000 observations and employ a structural equation model (SEM) to validate our findings. Interestingly, emissions increase by 1.75% if residential PV is adopted, and Japanese citizens with residential PV systems end up using 3.02% more electricity. We also find that pro-environmental consumers may also produce more emissions with PVs. As a result, reaching target carbon reductions in the residential sector would necessitate eliminating conventional energy sources. We address the policy implications for pathways to reduce residential emissions.

DOI： 10.1016/j.resconrec.2021.105924

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Repository Public URL： https://hdl.handle.net/2324/7182002

Language：English  

Language：Others   Publishing type：Research paper (other academic)  

DOI： 10.1088/1755-1315/505/1/012044

Language：Japanese   Publishing type：Research paper (scientific journal)  

本研究は，日本における小水力発電の普及に係る障壁と課題について，事業主体の視点から明らかとすることを目的とする。筆者らが小水力発電事業実施地域に入り込み行ってきた参与観察及び小水力発電事業者への聞き取り調査とアンケート，そして先行研究を基に，小水力発電の普及に係る障壁と課題を事業主体の視点から８つ特定し，大きく次の３つのカテゴリーに整理を行った：政治的要因カテゴリー，技術・インフラ的要因カテゴリー，事業主体形成・計画・資金調達要因カテゴリー。 小水力発電事業者へのアンケートを基に，特定された各要因の重要度を，階層化意思決定法を用いて分析し，各要因の重み付けを行った。再生可能エネルギー全般において障壁となっている系統連系の問題に加えて，小水力発電には多くの許認可手続きの課題，地域住民との関わり方を含めた事業主体の形成の重要性，長期を要する開発期間の短縮のための事業計画の重要性等が確認された。これらの課題を踏まえた事業主体の形成，資金調達，そして地域住民や各種ステークホルダーとの調整を行っていくことがこれからの小水力発電の普及において重要であると考察される。本研究は，事業主体の視点に焦点をあてることによって，小水力発電の普及に係る障壁と課題を詳細に明らかにしている。

DOI： 10.3775/jie.97.245

Event date： 2021.5

Language：English   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2021.1

Language：English   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2020.9 - 2021.9

Language：English   Presentation type：Oral presentation (general)  

Country：Germany  

Event date： 2020.5

Language：English   Presentation type：Oral presentation (general)  

Venue：日本   Country：Japan  

Event date： 2020.3

Language：English  

Country：Japan  

Event date： 2024.3

Language：Japanese   Presentation type：Oral presentation (general)  

Venue：九州大学   Country：Japan  

Language：Japanese   Publisher：毎日新聞出版  

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Language：Japanese   Publisher：Atomic Energy Society of Japan  

Nuclear fusion development by private sector (1): What is happening in the private fusion industry now

DOI： 10.3327/jaesjb.64.10_553

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Language：Others  

Hydrogen is a low or zero-carbon energy source that is considered the most promising and potential energy carrier of the future. In this study, the energy sources, feedstocks, and various methods of hydrogen production from power generation are comparatively investigated in detail. In addition, this study presents an economic assessment to evaluate cost-effectiveness based on different economic indicators, including sensitivity analysis and uncertainty analysis. Proton exchange membrane fuel cell (PEMFCs) technology has the most potential to be developed compared to several other technologies. PEMFCs have been widely used in various fields and have advantages (i.e., start-up, zero-emissions, high power density). Among the various sources of uncertainty in the sensitivity analysis, the cost estimation method shows inflationary deviations from the proposed cost of capital. This is due to the selection process and untested technology. In addition, the cost of electricity and raw materials, as the main factors that are unpredictable.

DOI： 10.3389/frsus.2022.943145

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Language：Others  

During the past two decades, the world has seen exponential growth in the number of companies reporting environmental, social, and governance (ESG) data, and various ESG metrics have been proposed and are now in use. ESG metrics play a crucial role as an enabler of investment strategies that consider ESG factors, which are often referred to as “ESG investments”. The ESG metrics and investment market are evolving rapidly, as investors, corporations, and the public are giving more priority to the “S” in ESG, including social equity issues, such as diversity, income inequality, worker safety, systemic racism, and companies' broader role in society. In this critical, systematic review, utilizing in-depth assessments, we investigate and compare the approaches employed in major ESG metrics and studies, then, we shed light on the “S” aspect by reviewing existing approaches used to assess social equity to clarify commensurability with ESG. Through the systematic review, this paper confirms that ESG investments can be expected to provide stable and high returns especially over the long term. This paper also clarifies how elements considered in social equity studies are largely reflected in major ESG metrics.

DOI： 10.3389/frsus.2022.920955

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Interest in reducing the greenhouse gas emissions from conventional power generation has increased the focus on the potential use of hydrogen to produce electricity. Numerous life-cycle assessment (LCA) studies of hydrogen-based power generation have been published. This study reviews the technological and methodological choices made in hydrogen-based power generation LCAs. A systematic review was chosen as the research method to achieve a comprehensive and minimally biased overview of hydrogen-based power generation LCAs. Relevant articles published between 2004 and 2021 were identified by searching the Scopus and Web of Science databases. Electrolysis from renewable energy resources was the most widely considered type of hydrogen production in the LCAs analyzed. Fuel cell technology was the most common conversion equipment used in hydrogen-based electricity LCAs. A significant number of scenarios examine the use of hydrogen for energy storage and co-generation purposes. Based on qualitative analysis, the methodological choices of LCAs vary between studies in terms of the functional units, allocations, system boundaries, and life-cycle impact assessment methods chosen. These discrepancies were likely to influence the value of the environmental impact results. The findings of the reviewed LCAs could provide an environmental profile of hydrogen-based electricity systems, identify hotspots, drive future research, define performance goals, and establish a baseline for their large-scale deployment.

DOI： 10.3389/frsus.2022.920876

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This study conducted a systematic literature review of the technical aspects and methodological choices in life cycle assessment (LCA) studies of the use of hydrogen for road transport. More than 70 scientific papers published during 2000-2021 were reviewed, in which more than 350 case studies of the use of hydrogen in the automotive sector were found. Only some studies used hybrid LCA and energetic input-output LCA, whereas most studies addressed attributional process-based LCA. A categorization based on the life cycle scope distinguished case studies that addressed the well-to-tank (WTT), well-to-wheel (WTW), and complete life cycle approaches. Furthermore, based on the hydrogen production process, these case studies were classified into four categories: Thermochemical, electrochemical, thermal-electrochemical, and biochemical. Moreover, based on the hydrogen production site, the case studies were classified as centralized, on-site, and on-board. The fuel cell vehicle passenger car was the most commonly used vehicle. The functional unit for the WTT studies was mostly mass or energy, and vehicle distance for the WTW and complete life cycle studies. Global warming potential (GWP) and energy consumption were the most influential categories. Apart from the Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation model and the Intergovernmental Panel on Climate Change for assessment of the GWP, the Centrum voor Milieukunde Leiden method was most widely used in other impact categories. Most of the articles under review were comparative LCA studies on different hydrogen pathways and powertrains. The findings provide baseline data not only for large-scale applications, but also for improving the efficiency of hydrogen use in road transport.

DOI： 10.1088/2516-1083/ac34e9

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DOI： 10.20790/easoc.2018.9_21