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Abstract Japanese energy system toward the mid-century has been assessed using an energy system model with inter-temporal optimization of total system cost, TIMES-Japan. The assessment framework couples the energy system model and detail sectoral models such as power system model, wind and solar power capacity potential models, and building energy model via soft-linkage. 70%, 80% and 90% emissions reductions targets at 2050 are assessed with varying assumption of carbon capture and storage (CCS) and nuclear power. It shows sensitivity in the final energy consumption of zero emissions carriers in transportation sector, particularly in LDV. Availability of power generation using biomass with CCS (BECCS) is also considered in the model to evaluate transitions of energy systems toward net-zero emissions after 2050. [ABSTRACT FROM AUTHOR]

Carbon Capture and storage may contribute as much as one-fifth of the necessary reductions to meet the IEA’s emissions goals for 2050. CCS is one of the only technologies that reduces the carbon impact of “business as usual,” preventing CO 2 from burning fossil fuels and certain industries from entering the atmosphere. Japan has geological, regulatory, and financial advantages encouraging investment in CCS and several demonstration projects are already underway. Using a Markel-Times system model, long-term road map results are presented for Japan’s future energy mix and CCS capacity. In the short term until 2030, import prices of fossil fuels are expected to increase while renewable solar and wind power will grow rapidly. The role of nuclear power is more debatable in the wake of the Fukushima disaster, but the projection anticipates at least some nuclear power to be used in the coming decades. Two industries are modeled for CCS, steel production and cement manufacture. Launched by start-up investments, CCS is expected to begin industrially from 2015 and could grow to capture and store more than 90 PJ of carbon from the steel industry per year and another 60 PJ from cement factories every five years. [ABSTRACT FROM AUTHOR]

We present a development strategy of low carbon scenarios that consider interaction of economically viable bioenergy and/or BECCS technological flow, biophysical limit of bioenergy productivity and food security. In the process, detailed bioenergy representations, including various bioenergy feedstock and conversion technologies with and without CCS, are implemented in an integrated assessment (IA) model, GRAPE (Global Relationship Assessment to Protect the Environment). Also to overcome a general discrepancy about yield development between ‘top-down’ IA models and ‘bottom-up’ estimates, we applied yields change of food and bioenergy crops consistent with process-based biophysical food crop models for bioenergy crops in changing climate conditions. Using the framework, economically viable strategy for implementing sustainable BECCS are evaluated. [ABSTRACT FROM AUTHOR]

In this paper, the significance of CO 2 -free hydrogen is discussed using a long-term global energy system. The energy demand–supply system including CO 2 -free hydrogen was assumed, though there are still large uncertainties as to whether a global CO 2 -free hydrogen energy system will be deployed. System analysis was conducted using the global and long-term intertemporal optimization energy model GRAPE under severe CO 2 emission constraints. Applied global CO 2 constraints for 2050 were a 50% reduction from 1990 levels. CO 2 constraints accounting for Intended Nationally Determined Contributions (INDCs) in each region were also considered. A variety of energy resources and technologies were considered in this model. Hydrogen can be produced from low-grade coal or natural gas with CO 2 capture and electricity from renewable energy. The hydrogen CIF (cost, insurance, and freight) price for Japan was about 3.2 cents/MJ in 2030. Hydrogen demand technologies considered in this paper are hydrogen-fired power plants, direct combustion, combined heat and power (fuel cells, gas engines, and gas turbines), fuel cell vehicles, and hydrogen internal combustion engine vehicles. The majority of CO 2 -free hydrogen was deployed in the transportation sector. CO 2 -free hydrogen was utilized in the power sector, where deployment of other zero emission technology has some constraints. From an economic viewpoint, CO 2 -free hydrogen can reduce the global energy system cost. From the viewpoint of a localized region, such as Japan, deployment of CO 2 -free hydrogen can improve energy security and environmental indicators. [ABSTRACT FROM AUTHOR]

Japan's energy consumption derives mostly from fossil fuels, which are un-secure and release a much greenhouse gas emissions. To meet goals of reducing GHG, hydrogen gas can be utilized in power generation in hydrogen fired and firing / co-combustion power plants. This paper analyses the impact of hydrogen in the power generation sector using the MARKAL-TIMES Japan optimization model framework. Two models are used: a base scenario without hydrogen and hydrogen scenario in which hydrogen is supplied from 2020 onwards. In the hydrogen scenario, other processes which are normally supplied by natural gas are reduced because the gas is instead used to generate power. Adding hydrogen to the energy supply leads to a decrease in projected use of fossil fuels. The hydrogen scenario produces fewer emissions than the base scenario; by 2050, the hydrogen scenario's estimated 388 metric tons of CO 2 emissions is over 250 tons less than the base scenario's emissions of 588 metric tons. [ABSTRACT FROM AUTHOR]

Abstract: Industries have various kinds of voluntary approaches to mitigate climate change through international industrial associations. Sector based intensity target based on the bottom-up technological information is proposed as one of climate policies and it is compatible with industrial voluntary approaches in many cases. Carbon dioxide capture and storage (CCS) technology is one of climate mitigation options in energy sector, especially in power generation. Energy, macroeconomy and climate modules in integrated assessment model GRAPE (Global Relationship to Protect the Environment) was used for the analysis. In relatively complex energy demand and supply representation in energy module, CO2 capture from power generation was assumed. The author assumed that CO2 intensity target would converge among global regions in the three energy sectors (i.e. power generation, transport, and other sectors) and that almost zero CO2 emissions will be realized in the end of 21st century. Sensitivity analysis was conducted by changing the CCS cost settings and degree of nuclear power capacity limit. CO2 capture power capacity role in the power generation portfolio and changes in generation cost is discussed. [Copyright &y& Elsevier]

• A whole-system energy analysis study is conducted using the TIMES-Japan framework. • The model follows a least-cost optimization approach. • The minimum amount of CCS capacity varies between 5 and 150 MtCO 2 by 2050 under different scenarios. • The minimum CCS capacity to achieve the emission target is heavily affected by availability of hydrogen imports and EAF. • There is no feasible scenario that achieves emission reduction goals without CCS. In order to achieve the Paris Agreement target of well below 2-degrees centigrade goal, developed countries have committed to reducing their emissions considerably during the coming decades. In order to achieve the ambitious target of an 80 % CO 2 emission reduction in Japan by 2050 (compared to 2013 levels), various energy efficient and low-carbon technologies on the supply and demand sides of the energy system must be deployed at reasonable cost. In this study, we investigate the possibility of achieving the emission reduction targets in Japan using the TIMES-Japan framework, which employs a least cost optimization approach. The contribution of carbon capture and storage (CCS) in achieving the emission reduction targets is studied in various scenarios as alongside the evaluation of two important emission reducing technologies in the same energy sector as CCS. Results of the analysis reveals the importance of hydrogen import on the supply side and the electrification of steel-making furnaces (EAF) on the demand side in order to obtain "feasible" scenarios. The minimum amount of CCS capacity is calculated for each scenario and the results vary between 5 and 150 million tons of CO 2 by 2050. The range of minimum CCS capacity is wide and affected by the availability of hydrogen imports and EAF for steelmaking in various scenarios; while extremely low CCS capacity results in a very high energy system cost. Based on the results of our analysis, policy implications for appropriate levels of CCS, hydrogen import and EAF deployment are discussed. [ABSTRACT FROM AUTHOR]

Study Objective: Hypertension or hypotension in patients receiving continuous infusions of dexmedetomidine (DEX) is often due to changes in vascular resistance caused by α2 receptor stimulation. We investigated whether baseline perfusion index (PI) and pleth variability index (PVI), derived from pulse oximetry readings, could predict DEX-induced changes in the hemodynamic status in spontaneously breathing patients.Design: Observational study.Setting: Operating room.Patients: Patients (American Society of Anesthesiologists performance status 1 or 2) scheduled to undergo lower extremity or abdominal procedures under regional anesthesia were approached.Interventions: The PI and PVI were set as baseline upon arrival in theater and were then measured at 2.5-minute intervals. Upon attaining stable hemodynamic status under spontaneous breathing, intravenous administration of DEX was initiated at 6 μg kg(-1) h(-1) for 10minutes, followed by continuous infusion at 0.6 μg kg(-1) h(-1).Measurements: Blood pressure, heart rate, PI, and PVI were measured. Hypertension was defined as an increase in systolic blood pressure (SBP) >15% and hypotension as a decrease in SBP <15% from baseline.Main Results: Baseline PI and PVI correlated with the degree of change in SBP. The maximum percentage increase as well as the maximum percentage of decrease in SBP from baseline correlated with baseline PI (r=0.418 [P=.005] and r=0.507 [P<.001], respectively) and PVI (r=-0.658 [P<.001] and r=-0.438 [P=.003], respectively). PVI <15 identified DEX-induced hypertension (sensitivity 94%, specificity 85%) and PVI >16 identified DEX-induced hypotension (sensitivity 83%, specificity 64%).Conclusions: PVI may predict DEX-induced changes in blood pressure in spontaneously breathing patients. [ABSTRACT FROM AUTHOR]

Abstract 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. Highlights • We analyze the energy system scenarios to achieve 80% reduction in carbon dioxide emissions by 2050. • We employ six integrated assessment models to reveal decarbonization challenges in the energy system. • The model results show that the industrial sector has a large final energy share and significant residual carbon dioxide emissions under the 80% reduction scenario. • We also show that Japan's mitigation scenarios are accompanied with high marginal costs of abatement. [ABSTRACT FROM AUTHOR]