The Institute of Energy Economics, Japan

Surface-assisted DNA lattice assembly is used in the synthesis of functional surfaces and as a model of supramolecular network formation. Here, competitive DNA binding of different cation species is investigated by molecular dynamics simulations and correlated with experiments of surface-assisted DNA origami lattice assembly. The results demonstrate that cation-DNA binding has a strong impact on lattice assembly and order.

Climate change is expected to cause more frequent and severe water-related disasters. Although dams effectively control floods in watersheds, the number of suitable dam sites in Japan is limited. Therefore, there is a growing need to increase the flood control capacity of existing dams; thus, the need for dam rehabilitation is increasing. Among possible measures, dam heightening is an effective means of dam rehabilitation. This study examines the Shin-Katsurazawa Dam, which is a case of coaxial heightening of a concrete gravity dam. (1) The mechanical properties of the existing dam concrete, which is 67 years old, were determined based on the results of material tests of core specimens. The validity of the test results was confirmed through a reproduction analysis of the dam during an earthquake. (2) It was clarified that concrete placement at relatively high elevations should ideally be planned when the reservoir water level is relatively low if the reservoir is to be operated all year round. (3) The seismic behavior of the dam after heightening was reproduced, and the physical properties of the existing dam were identified. Based on the results, the mechanical properties of the heightened dam concrete did not reach those of the existing dam concrete due to the young age of the material. (4) After heightening, the Shin-Katsurazawa Dam was predicted to have a greater external stability in terms of sliding at the dam base than the existing dam.

ABSTRACTDrawing insights from virtue ethics and psychological perspectives on empathy, we propose a framework for integrating empathy, ethics, and efficacy (3E) to guide the responsible development and deployment of artificial intelligence (AI) technologies in consumer service encounters. It encourages developers, vendors, and users to improve efficiencies and productivity but, more importantly, to adopt an empathetic perspective with ethical decision‐making during AI development and deployment. By simultaneously adopting descriptive, analytical, and prescriptive approaches to engage academics, practitioners, and public policymakers, we outline a future research agenda for enriching AI‐consumer service encounters. Beyond conceptual integration, the framework offers practical insights for AI designers, businesses, and regulators by emphasising empathy as a bridge between efficacy and ethics. This perspective supports the development of AI technologies that not only enhance operational effectiveness but also foster consumer trust and well‐being, ensuring AI‐driven services remain human‐centred and ethically sound. A structured decision‐making model demonstrates how AI‐driven services can balance automation with ethical considerations and empathetic engagement, offering a pathway for more responsible AI implementation.

We study Japan’s net-zero emissions target by 2050 in a multi-model framework, focusing on residual emissions and carbon dioxide removal (CDR). Four energy-economic and integrated assessment models show similar but stronger strategies for the net-zero target, compared to the previous, low-carbon policy target (80% emissions reduction). Results indicate that around 90% (inter-model median) of the current emissions are reduced through abatement, including improved energy efficiency and cleaner electricity and fuels. Models deploy new options such as CDR based on carbon capture and storage (CCS) (bioenergy with CCS and direct air carbon dioxide capture and storage) and hydrogen to achieve net zero. The scale of CCS-based CDR deployment reaches an inter-model median of 132Mt-CO2/yr. The median hydrogen share of final energy in 2050 increases from 0.79% to 6.9% between the low-carbon and net-zero scenarios. The CDR sensitivity analysis reveals that limiting the use of CDR significantly increases the mitigation costs for net zero. Achieving Japan’s net-zero goal will require exploring methods to reduce residual emissions, including demand-side solutions, and accelerating responsible CDR policies.

This paper evaluated the energy security performance of Malaysia within the timeframe from year 2000 to year 2050. For the projected periods, an implementation of several energy security scenarios which include Business-As-Usual scenario (BAU), Asia Pacific Energy Centre Target scenario (TGT) and 2 Degree Celsius scenario (2DC) were applied to provide an understanding of their impact to the energy security performance should one of them being enforced. The study consists of designing of energy security indicators based on 4As Framework, collecting energy data from various publications, calculations of indicators and result representations, as well as analysis and improvement of current energy policies based on the findings. The results for all scenarios have shown a significant similarity of the shifting of performance from “Availability” and “Affordability” dimensions to “Applicability” and “Acceptability” dimensions. This shows challenges such as insufficient energy resources to fulfil the demand and rising price of energy will be a great threat to the government and policy makers to improve the energy policy and resolve those issues.

An increasing number of governments worldwide recognize the potential of agrivoltaics. However, the current legal frameworks and land-use policies are still a limiting factor for a broader expansion of agrivoltaics. This preliminary study compares the legal and policy frameworks in Japan, South Korea, Taiwan, Germany, and Massachusetts in the United States to identify common barriers and learning opportunities. The comparative study revealed positive changes for agrivoltaics in most countries in recent years, but many obstacles remain. To unleash the full potential of agrivoltaics, we suggest (1) advancing the institutionalization of agrivoltaics, (2) improve the social acceptance of agrivoltaics, and (3) provide financial incentives specifically for agrivoltaics. Many promising good practice examples to advance these three objectives already exist in the analyzed countries, showing the importance of knowledge sharing in the relatively new field of agrivoltaics to facilitate a fast expansion and avoid costly mistakes.

Due to growing concerns over climate change, as well as to the recent cost declines, variable renewable energies (VREs), such as wind and solar PV, have seen rapid deployment over the past few years. High penetration of VREs, however, requires additional costs caused by the intermittency, e. g. those for grid expansion, for deploying power storage systems, and for power curtailment. Thus the total system cost becomes larger than the cost measured simply by the traditional metric known as the levelized cost of electricity (LCOE), which has long been used for estimating the economics of the power sector. This paper proposes a methodology to assess these additional “system integration costs”, as well as to decompose them into several subcategories, using two complementary mathematical optimization models. It also applies the methodology to Japan's power system in 2030, in the aim of obtaining insights into the key factors that determine the changes in the power sector under high penetration of VREs. The results show that in a case with a solar PV capacity of 64GW and a wind capacity of 10GW, the system integration cost divided by the total power supply amounts to 0.41JPY/kWh. Reduction in the load factors of conventional power generation facilities accounts for the largest part of the system integration cost at 0.30JPY/kWh, highlighting the need for appropriate policy measures that ensure the adequacy of power systems.

In the original publication of the article, the incorrect file was published as supplementary material.

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.

Dynamic wireless power transfer (WPT) can solve the short cruising range problem of electric vehicles; moreover, it makes electric vehicles more efficient due to reducing heavy battery of electric vehicles. However to be stopped transmission of dynamic WPT by foreign matter objects is one of the major problems of dynamic WPTs. Prevention of the entry of foreign objects between the transmitter and receiver coils is the best method to increase the opportunity WPT and energy of WPT. This article aims to propose a new WPT system named in-wheel coil, which can prevent foreign objects by power transfer through tire and wheel, and also proposes its suitable materials and design. The nonmetal materials of wheels and tires for the proposed system are evaluated by actual measurement with small evaluation equipment; hence, the suitable materials that decrease WPT efficiency hardly are proposed. The proposed system is also evaluated by full-scale model with power transfer test. In addition, the mutual inductance model of arc-shaped coil, which can minimize airgap between the transmitter coil and the receiver coil.