Access to affordable, clean energy and its growing consumption have often been directly linked with socio-economic development. As one of the fastest developing countries, Bangladesh has been experiencing stable GDP growth with an increasing trend for the last ten years. This growth has initiated excessive demand for energy, especially in the electricity sector. Within just a decade, both the total electricity generation capacity and per capita electricity generation have almost doubled. In order to meet this growing demand and keep pace with the development trend, sectoral demand growth projection for near and long-term planning and execution is essential. Model for Analysis of Energy Demand (MAED)-2 tool provided by International Atomic Energy Agency (IAEA) was used in this study to predict the future energy demand in Bangladesh from the year 2020 to 2050. The energy-economic data of the year 2015 is considered as the base data. Future energy demands based on different socio-economic and demographic development scenarios have been projected and decomposed into sectoral demands that identifies the transition of a traditional agriculture-based society in to an industry-service oriented society. The insights obtained from analysis could be further utilized in policy development for energy security and climate change actions so that the development would be sustainable.

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The vehicle electrification, the replacement of engine vehicles by hybrid (HV), electric (EV) and fuel cell vehicles (FCV) is expected to reduce CO₂ emissions in transport sector. However, the reduction amount by EV and FCV is largely affected by CO₂ emission intensity of power system and the way to make hydrogen. Authors simulate a power system in 2030 where a large amount of PV is implemented, and PV generated energy must be curtailed on many days. The annual cost is minimized by optimizing the hourly output of coal fired and LNGCC plants, when the 16% of passenger vehicle mileage is replaced by EV charged at midnight and/or daytime. In FCV case, the capacity of water electrolysis and hydrogen tank, and the hourly electrolysis output as well as thermal power plant output are optimized. Results show CO₂ emissions decrease particularly when EVs are charged at daytime and the charging power is controlled to contribute frequency stability. The electrolysis demand decreases the PV energy curtailment but increases the CO₂ emission because of the lower energy converting efficiency and higher facility cost. The energy chain including whole power system, demand and fuel is analyzed to see the power flow and CO₂ emission.

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This paper presents the analysis of the energy, upward reserve, downward reserve, and load frequency control (LFC) regulation in future energy systems in Japan, through the simulation of the co-optimization of economic dispatch control (EDC) and LFC considering uncertainties of electricity load and photovoltaic output. The results show that, in the present Kyusyu situation, a lot of photovoltaic output is absorbed by pumping up the water and photovoltaic curtailment. Also, most of the upward and downward reserve are provided from LNG combined cycle. Finally, the overall system changes dramatically when photovoltaic output is largely different from its predicted value. Specifically, the shadow price of the LFC requirement has a large standard deviation compared to its mean value, which makes it difficult for companies to join the ancillary service market.

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This study aimed to analyze the economic impact of the Nationally Determined Contributions (NDCs) under the current policies related to climate and energy. The study evaluated international competitiveness for 2030 using a global energy-economic model. The assessment of the macroeconomic impact of NDCs indicates that large differences between countries regarding marginal abatement costs are estimated and that the economic effects differ greatly between countries. The developed countries with relatively ambitious targets are adversely affected, especially in terms of the productions and exports of energy-intensive industries. With substantial differences in policy stringencies among regions, carbon leakage is induced through international trade, which represents production shifts from the developed countries with high marginal abatement costs to some developing countries with almost zero marginal costs. There is a risk that the effectiveness of emission reductions worldwide is reduced significantly, which is a serious concern. Such excessive adverse effects on the international competitiveness of developed countries may result in a decline in the production of and investment in environmentally friendly products, thus decreasing the international contribution and technological development and diffusion.

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This paper aims to study how secondary energy should be towards 2050 and beyond where renewable energy plays a major role as energy sources. First, the paper investigates the time distribution of surplus power in various scenarios using a power supply and demand analysis model. Next, this paper conducts the economic analysis including capital and operation costs, assuming the capital investment and operation of hydrogen production and storage equipment. The result indicates it is highly possible under certain circumstances in the future, where renewable energy power generation expands that, coexisting with and complementing power storage technology, new forms of energy system based on the production, storage, and use of secondary energy such as hydrogen will be established in an economically feasible manner.

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The Paris Agreement including long-term goals of 2 ℃, 1.5 ℃ and net zero emissions in the second half of this century. Natural gas is the lowest emissions per calorie among fossil fuels and can contribute to CO₂ emission reductions. On the other hand, it is one of the fossil fuels and emits CO₂ through its combustion. There are uncertainties in long-term emission reduction pathways or timings even for the 2 ℃ goal for example due to its different achieving probability of the temperature target. In addition, there are large uncertainties in technologies and socioeconomic conditions. This study evaluated the role of natural gas as medium- and long-term global warming countermeasures in the world and Japan by using a global energy systems model having disaggregated regions and detailed technology descriptions. The energy systems focusing natural gas until 2050 were discussed but the model estimated them intertemporally until 2100 including net CO₂ zero emissions for the 2 ℃ scenario. According to the analyses, natural gas will play a larger role for emission reductions until 2050 both in the world and Japan even for the deep emission reduction pathways consistent with the 2 ℃ goal. Co-generation systems will play a large role in all of power, industry and residential and commercial sectors particularly in Japan in general, while the contribution becomes small when the utilization of heats is limited.

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To estimate the energy use reduction due to energy saving measures, it is necessary to understand the current state of energy consumption considering difference of energy use among households. In this paper, a multinomial logistic regression model which predicts the appliance ownership status from household attributes was developed using government statistics (Household CO₂ Statistics, 2014). By integrating this model with the residential end-use energy simulation model, the residential sector energy consumption of Japan was calculated. As a result, it is clarified the household using a lot of energy owns more appliances than the others. Comparing the energy simulation result and actual energy consumption from the Household CO₂ Statistics, it was verified that the variation of the energy consumption close to the actual situation can be reproduced. It was also shown that the largest cause of error between simulation results and statistical values was due to the differences in resident lifestyle and occupant’s behavior. Furthermore, it was demonstrated that households that were underestimated in the simulation model had more energy consuming behavior and lower energy saving awareness than standard households.

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After flexibility market will be established in Japan in 2021, the role of demand response (DR) will not be only for securing capacity (kW) and adjustment of power consumption (kWh), but also for adjustment of the power grid (⊿kW).
Services which require faster response generally have higher market prices because limited resources are able to bid. DR services might be continuously monetized with the balancing market. To consider commercialization of DR and Virtual Power Plant (VPP) in Japan in the future, it is important to watch the foreign cases where ancillary service market operations are ahead, and to investigate price level and resource type there.
We clarified price trends in three markets in the UK, Germany and the US, and resource type trends. In the UK and Germany, we conducted interviews with DR operators who hold demand-side resources to understand the actual situation and future directions.

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Seaweed contains high high-density glucose, from which ethanol or materials such as biodegradable plastic, have been recently produced. A floatable block made from waste glass, that saves on labor and costs, has been developed to culture seaweed. Seaweeds collect nutrients such as nitrogen and phosphorus from eutrophic areas during cultivation. This floatable block would be able to supply nutrients, via a slow release method, in oligotrophic areas; this would constitute most of the exclusive economic zone (EEZ) in Japan. A shortfall in phosphorus supply is feared in the near feature, thereby making it necessary to obtain it from deep sea water through the cultivation of seaweed.
The material for the floatable b lock would be supplied from coal ash or incineration ash, and so on by separating rare earth metals and metals using a high high-temperature melting furnace. The separated rare earth metals and metals may be recycled. Large volumes of ethanol made from seaweed can be used as a motor fuel. As the exhaust gases from an ethanol ethanol-fueled car are more toxic than those from a conventionally fueled one, under low low-temperature operation, catalyst activity would need to be assisted by electric discharge with a switching dev ice, namely MOS MOS-assisted gate triggered thyristor (MAGT), which achieves both high speed and high capacity. MAGT was developed for excimer laser.

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