In the trend toward decarbonization, electric vehicles are also being introduced into the home delivery business, but the devel-opment of charging facilities is a challenge. In addition, dynamic pricing, in which electricity rates fluctuate depending on the time of day, is about to be introduced due to oversupply of daytime electricity from solar power generation. We consider the efficient use of surplus electricity during the day for delivery business. This study quantitatively demonstrates the effect of dy-namic pricing by using a mathematical optimization model to determine the optimal delivery route and charging plan in response to the fluctuating electricity prices. As a result, effects such as an increase enroute charging by daytime electricity, reduction in charging costs, and promotion of renewable energy use were observed. It is also shown that by taking the next day’s electricity prices into account, it is possible to plan more effective use of inexpensive electricity, and greater effects can be seen.

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In this study, the geographical distribution of gas demand in Aichi Prefecture, which ranks first in Japan in terms of gas demand from the manufacturing industry, was determined, and hydrogen demand potential was estimated based on an assumed scenario for the installation of hydrogen pipelines.
The main results are as follows:
1) Estimation of geographic distribution of gas demand in Aichi Prefecture
Gas demand from the manufacturing industry was estimated for all towns and cities in Aichi Prefecture. For the estimation, we constructed a method to determine the availability of gas supply for each region from map data published by gas supply companies.
2) Assumption of hydrogen pipeline installation scenario and estimation of hydrogen demand potential
Based on the results obtained in 1) and the locations of thermal power plants, which were assumed to be important hydrogen consumption and supply centers, three scenarios for installing hydrogen pipelines were assumed, and the demand potential for each was estimated.

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In Japan, retail electricity suppliers are required to notify their daily electricity supply schedules relying on uncertain information, creating a risk of imbalance in power supply and demand. As a solution to this problem, the utilization of distributed energy resources that are ubiquitous in electric power grids is attracting attention. A typical resource is electricity demand, which can be coordinated by energy resource aggregators under demand response programs (DRs). On the other hand, as customers cooperate with the DRs, their contracted retail electricity suppliers lose the opportunity to sell electricity. Therefore, the energy resource aggregators need to financially offset the opportunity losses of the retail electricity suppliers. This is the compensation for negawatt electricity trading. The authors propose a method for calculating the monetary unit of negawatt compensation that takes into account the equality of profit distribution between the retail electricity suppliers and the energy resource aggregators. In the proposal, electricity trading is represented using a framework of social welfare maximization, allowing the value of changes in the profits of retail electricity suppliers, energy resource aggregators, and customers to be measured. This property is exploited to define the optimal unit of negawatt compensation based on the Nash bargaining solution.

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This study proposes a solar/wind hybrid energy system assisted with battery storage to examine the feasibility and strategies of domestic green hydrogen production in Japan in the 2030s. An optimization model of the proposed system utilizing linear programming is developed to determine promising production locations as well as the optimal capacity and operation of each modeled technology. As input data for the model, meteorological data of ERA5, which has a geographical resolution of 0.25° and a temporal resolution of one hour, is processed into power generation data of solar PV and wind. Economic and technical assumptions are adopted from publicly accessible reports and literature. We find that with cost results around 25-30 Yen/Nm³, coastal regions in Tohoku might be promising. A comprehensive sensitivity analysis is conducted to examine the influence of WACC and each technology’s economic assumptions on production cost. Furthermore, selecting AREH project located in western Australia as a reference, domestic production is compared with overseas production in the same method.

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The purpose of this paper is to clarify the total project costs per kW of onshore wind power facilities in Japan and clarify what factors affect the project unit costs. We collected and organized data on onshore wind power generation facilities in Japan. The coverage of the collected project cost data was 48.9% based on the number of facilities and 55.8% based on capacity. The multiple regression analysis yielded the following main results: i) The larger the single unit capacity, the lower the project unit cost. In other words, larger wind turbines contribute greatly to lower project unit costs; ii) The newer the equipment (the more recently it started operation), the higher the total project unit cost tends to be; and iii) By converting project unit costs into real U.S. dollar prices, we confirmed that project unit costs have been on a downward trend since around 2010 or 2012. However, this decline is largely due to the increase in single unit capacity, i.e., the larger size of wind turbines.

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To address the challenge of managing the output of renewable energies, it is advisable to implement a strategy of increased demand response, which increases electricity demand during the daytime. However, there are concerns about the increased cost burden on the customer side and the need to balance the economic benefits of providing incentives to electricity retailers. In December 2023, we demonstrated the efficacy of increased DR using storage batteries. As a result, we were able to confirm a DR effect of about 3 kWh per household, as well as a 6.8% reduction in CO₂ emissions. The encouraging results indicated that only about 30% of all households had increased costs. Furthermore, the electricity retailer may be able to ensure a profit and loss balance even if it fully compensates for the amount borne by consumers. Additionally, we found that implementing continuous DR for a certain period is the optimal approach for considering the economic benefits for consumers and electricity retailers. Now, we are preparing to launch the new service to facilitate the greater use of renewable energy and reduces CO₂ emissions.

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