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The equipment energy efficiency improvement policy (EEEIP) is one of the important measures of energy conservation and emission reduction in various countries. However, due to the simultaneous implementation of variety policies, the effect of the single policy cannot be clearly reflected. In this paper, a method of identification and evaluation of EEEIP was proposed, and the application was verified by analyzing the example of EEEIP in Japan (Top Runner policy, TRP). Firstly, through the factor decomposition model, this paper studied the energy conservation and emission reduction potential of this policy area in Japan. Then, the TRP was identified by using moving windows and correlation analysis, and the impact of specific equipment in TRP was analyzed. Finally, through the calculation of the rebound effect of the carbon footprint (REC), this paper analyzed the energy consumption and emission reduction effects of TRP in the short-term and whole life cycle. It showed that the policy has a good effect in tertiary industry and transportation, while the effect in residential is poor. For life cycle, the TRP of air conditioning and passenger car can bring better CO2 emission reduction effect, but the emission reduction effect of lighting is basically offset. [ABSTRACT FROM AUTHOR]

With the continuous increase in carbon dioxide emissions due to human activities and the resulting severe climate issues, there is global concern about energy conservation and emission reduction. However, detailed data on energy consumption and emissions at a fine-grained scale, particularly regarding spatial dimensions and sector-specific emissions, remains insufficient and in need of refinement and timely updates. In Japan, following the Fukushima nuclear disaster, there has been a significant shift from nuclear power generation to reliance on fossil fuels across various sectors, highlighting disparities in emissions data across different regions and industries. Our work extends the emissions time series for Japan's 47 prefectures, incorporating their socioeconomic characteristics over a broader time frame and with a more detailed sectoral classification. The emissions inventory, covering the period from 1990 to 2020, is based on the consumption of the three main fossil fuels across 32 sectors, with emissions carefully allocated for regional power generation. This dataset, presented in a unified format, is expanded to include longer time scales and more detailed socioeconomic data. It is anticipated to offer crucial insights for establishing regional emission reduction targets and identifying sectoral priorities for decarbonization. [ABSTRACT FROM AUTHOR]

• Operating time of SMEs is estimated using a SOM and hourly demand data. • The estimated operating time is used for hourly AC demand disaggregation. • The average errors of yearly AC demand estimation are better than 10%. • Hourly disaggregation highlights season and time period of AC demand peaks. Despite the growing penetration of smart meters and energy management systems in recent years, few tools have been proposed for energy demand data analysis and visualization to promote energy conservation in small- and medium-sized enterprises (SMEs). In this paper, we propose a new method consisting of operating time estimation and simplified disaggregation based only on the SME's hourly electricity demand data and actual outdoor temperature data. The method first estimates the operating time using a self-organizing map, which categorizes the hourly data as operating, half-operating, or non-operating time and eliminates manual parameter adjustment that requires user trial and error. Then, using the estimated operating time, our simplified disaggregation method estimates hourly air conditioning (AC) demand considering the variation in each office's temperature at which air conditioners are switched on. The method was evaluated using a public business energy management system dataset from Japan, and the average errors of yearly AC demand estimation were better than 10%. The outputs of the proposed method may provide information that is more relevant, reliable, and specific to each customer and efficiently promote energy conservation measures in SMEs. [ABSTRACT FROM AUTHOR]

The present paper suggests fuel consumption modeling for HDVs based on the code from the Japanese Ministry of the Environment. Two interpolation models (inversed distance weighted (IDW) and Hermite) and three types of fuel efficiency maps (coarse, medium, and dense) were adopted to determine the most appropriate combination for further studies. Finally, sensitivity analysis studies were conducted to determine which parameters greatly impact the fuel efficiency prediction results for HDVs. While vitiating each parameter at specific percentages (± 1%, ± 3%, ± 5%, ± 10%), the change rate of the fuel efficiency results was analyzed, and the main factors affecting fuel efficiency were summarized. As a result, the Japanese transformation algorithm program showed good agreement with slightly increased prediction accuracy for the fuel efficiency test results when applying the Hermite interpolation method compared to IDW interpolation. The prediction accuracy of fuel efficiency remained unchanged regardless of the chosen fuel efficiency map data density. According to the sensitivity analysis study, three parameters (fuel consumption map data, driving force, and gross vehicle weight) have the greatest impact on fuel efficiency (± 5% to ± 10% changes). [ABSTRACT FROM AUTHOR]

This paper measures the effects of information on residential demand for electricity, using data from a Japanese experiment. In the experiment, households had a continuous-display, electricity use monitoring device installed at their residence. The monitor was designed so that each consumer could easily look at graphs and tables associated, with the consumer's own usage of electricity at any time during the experiment. The panel data were used to estimate a random effects model of electricity and count data models of monitor usage. The results indicate that monitor usage contributed to energy conservation. [ABSTRACT FROM AUTHOR]

Combined heat and power (CHP) is crucial for promoting thorough energy conservation and advanced energy use, aimed toward greenhouse gas reduction. Solid oxide fuel cell (SOFC)-CHP is expected to be introduced as a measure against global warming and has been the focus of attention, and this study examined the effects of its introduction. This study introduces a linear programming evaluation model that can simulate optimized facility configuration and operation, based on the power supply and demand. The novelty of the proposed model is the consideration of geographic characteristics, which influences parameters dependent on gas transportation infrastructure and electricity. A sensitivity analysis was conducted considering the number of units and location of SOFC-CHP introductions in the National Capital Region of Japan. As a result, it was predicted that SOFC-CHP would likely begin to be introduced in areas where there is a large shadow price difference between electricity and gas at each node. The total power generation will decrease, as transmission and distribution losses decrease, owing to the diffusion of SOFC-CHP installed in the vicinity of demand. The widespread use of SOFC-CHP is an economically feasible CO2 emissions reduction pathway. These results will help assess the introduction of various distributed power sources in addition to SOFC-CHP to reduce CO2 emissions. [ABSTRACT FROM AUTHOR]

This paper focuses on households’ development of new energy-efficient habits as demonstrated in the context of a major electricity shortfall event. Energy conservation policies should encourage households to take measures that are actually effective in reducing energy consumption and that can be sustained over long periods of time. Few studies, however, have empirically examined what types of energy-saving measures are actually effective and persistent. The electricity shortages following the 2011 Great East Japan earthquake, tsunami, and nuclear disaster provided an opportunity to examine this question. A web survey of households in Japan was implemented to obtain data on metered electricity use in the summers of 2010–2013, household behaviors for electricity savings, and household socioeconomic attributes. Regression analysis was conducted to explain the effectiveness and persistence of energy saving behaviors. Results indicate that most households took several electricity-saving measures after the disaster to adapt to the electricity shortage. Certain types of measures led to 2–4% savings in electricity consumption (per measure) and persisted for two years. The effective and persistent electricity-saving measures tended to be those that did not require either frequent efforts or considerable discomfort. Findings suggest that electricity-saving behaviors requiring infrequent effort and little discomfort can become engrained as new habits or lifestyles. In particular, one promising measure may be to lower the electricity-usage settings of appliances. [ABSTRACT FROM AUTHOR]

The progress in the adoption of market mechanisms for climate change is overall laggard in Japan and the related study on business policy perspective is limited. Aiming to close the research gap, this paper measures Japanese company's awareness and approval of market-based instruments for energy saving, including financial subsidies, carbon taxes and greenhouse gases emissions trading schemes. The relationships between company's policy awareness and approval with pre-classified determinants are identified by econometric analyses. The data were collected from 230 respondents by a questionnaire survey in Hyogo prefecture. Overall, the sampled companies are confirmed to have low awareness and modest approval of market-based instruments currently. Significant and positive relationship exists between a company's size and its policy awareness. Financial subsidies and tax credit are preferable while carbon pricing policies are barely acceptable for the companies. A company's policy approval is significantly determined by the company's characteristics, such as organizational size and sector belongings. Empirical evidences from this analysis facilitate the understanding of business opinions on market-based instruments in Japan. The Japanese government is suggested to make efforts in promoting the industrial policy awareness and approval with a focus on specific categories of companies. [ABSTRACT FROM AUTHOR]

Abstract: This paper seeks to measure industrial energy saving activities (ESAs) and identify their determinant factors via an empirical study of companies in Hyogo, Japan. The surveyed companies exhibit high participation ratios in the pre-listed ESAs, especially those related to managerial measures. The classified factors are partly confirmed by econometric analysis. Whereas external pressures do not appear to alter the level of involvement of a company in ESAs, internal factors show a significant and positive influence. These findings point to the need for higher levels of support for industry as a whole from policy makers and industrial associations, to enhance energy saving practices within industry. [Copyright &y& Elsevier]

Abstract: In the mainland of China, the constraints of environments, resources, especially energy resources, has increasingly become the bottleneck of economic development after reform policy for more than thirty years. In this paper, we illustrate the basic structure of energy conservation and emission reduction from historic, institutional and comparative analysis based on Japan''s case as an example of energy conservation. Our investigation shows the evolution of Japan''s energy conservation policies from a view of energy security to the view of environment protection and low carbon economy. We also analyze the tools that Japan adopted to remove energy conservation barriers. [Copyright &y& Elsevier]

Abstract: With the development of distributed generation (DG) technologies and the implementation of policies to encourage their applications, building combined heat and power (BCHP) is expected to play a greater role in the commercial buildings in the future. BCHP is a promising efficiency improvement and carbon mitigation strategy, but careful selection of technology and operation mode is required to achieve a reasonable system performance according to energy consumption characteristics of buildings and technical features of equipments. This paper analyzed energy consumption characteristics of four typical commercial buildings in Japan and simulated the energy system performances of four mostly widely adopted DG technologies under different operation mode conditions for the four buildings studied. Various scenarios were evaluated and compared regarding energy utilization efficiency, energy saving and environmental effects, as well as economic efficiency. Results show that the hotels and hospitals are more attractive for BCHP because of their stable thermal load demands and a favorable heat-to-power ratio, which is the most compatible match with available DG technologies. Furthermore, some DG technologies are more suitable for a certain type of building than others because of their technical features more matching with the building’s energy consumption characteristics, as well as the user’s motivation of selecting BCHP. In Japan, during selecting DG technologies, the prior order is gas turbines (GT), gas engines (GE), diesel engines (DE) and phosphoric acid fuel cells (PAFC) for the hotels, PAFC, GE and GT, DE for the hospitals, PAFC, DE, GE and GT for the stores, as well as DE, PAFC, GE and GT for the offices. [Copyright &y& Elsevier]

Recent years, the energy consumption and carbon emissions released from the residential sector have increased rapidly due to the improvement of living standards. Japan, as one of the most developed countries worldwide, is found to be the fourth largest CO2 emitter in the world. Meanwhile, Japan is currently promoting social electrification from varied aspects. And this action further brings the household residential consumption to the vital place for overall energy conservation and emission reduction plans. Although electricity consumption and prediction analysis have been widely discussed. However, previous studies mainly focused on the estimation and analysis of energy consumption at the national level, without enough discussion from prefecture-level insights. To bridge this knowledge gap, this study established a factor-based bottom-up model to estimate the electricity consumption and carbon emissions during the 2015–2040 periods in the Japanese residential sector, considering the prefectural characteristics including per capita gross domestic product, population size, household size, residential floor space area, lifestyle, weather condition, and transition effect of appliance in the future. Nine scenarios that combine three levels of household size and three levels of growth of per capita gross domestic product are taken into account to estimate the electricity consumption for space heating and cooling, water heating, cooking, and appliances. Results indicate that the total residential electricity consumption will reach a peak during 2020s. The total carbon emissions will keep decreasing by 51.14–72.16 Mt between 2015 and 2040. Based on the results of this paper, policy recommendations are given for the Japanese government. • A factor-based bottom-up model is established for electricity consumption estimation. • The electricity consumption and carbon emissions are analyzed at a prefecture-level in Japan. • Each component of the residential sector electricity consumption is quantified completely and accurately. • The estimation results consider the lifestyle, weather conditions, and the transition effect of appliances in Japan. [ABSTRACT FROM AUTHOR]

Today in Japan, comfortable lifestyle and environment realized by abundant electric power is being questioned by energy consumption reduction policies called"cool biz" in summer, and "warm biz" in winter. One reason of these policies is the bad energy consumption efficiency of current air-conditioning systems that cool or warm indirectly human body. Several researches have been investigating the effect of direct human body cooling and warming. However, most proposed solutions focus on direct head or neck cooling, using ice to cool a water circulating system, such temperature during use cannot be controlled accurately nor adapted to user and environment conditions. Recently, a Japanese research team developed a portable system using Peltier elements that can both cool and warm neck. Though cooling was demonstrated to affect positively both physiological and psychological state in summer heat environment, in cold climate it could be confirmed for only neck warming but not feet and hands. In our objective of developing effective energy saving technology for direct temperature-conditioning of human body, and in order to reduce the discomfort caused by body chillness, we have proposed and developed a Peltier element based wrist-mounted wearable device that directly warms human body. A first experimental study showed how wrist warming rhythm affects hyperthermic sensation. Then, we verified whether the thermal sensation of the body, including the extremities, is improved by changing the position where the wrist is warmed. [ABSTRACT FROM AUTHOR]

This paper measures the metafrontier total-factor energy efficiency (TFEE) of 47 regions in Japan for the period 1996-2008, using the stochastic frontier analysis (SFA). The two-step output-oriented SFA approach by Huang et al. (J Prod Anal 42:241-254, 2014) is followed but converted into a two-step input-oriented SFA approach. The metafrontier TFEE is defined as a product of the group TFEE and the technological gap ratio (TGR). The mean group TFEE is smaller than the mean TGR for both the groups, which shows that the energy inefficiency in Japanese regions with respect to the metafrontier comes from primarily operating inefficiency, rather technology gap. The mean metafrontier TFEE of the metropolitan areas is smaller than that of rural areas, implying that the former is energy inefficient than the latter. The mean TGR of the metropolitan areas is also smaller than that of rural areas, implying that many Japanese regions with major cities are far below the metafrontier and still have much room for energy savings. [ABSTRACT FROM AUTHOR]

Electric bidets have become widespread in Japan and are now rapidly being installed across the rest of Asia, the United States, and the European Union. However, the impact on water infrastructure has not yet been sufficiently evaluated. Using Japan as an example, we assess the impact of the spread of electric bidets on the existing water infrastructure and use the results to predict the impact in countries in which the spread of electric bidets is expected in the future. In this study, we first proposed a model of electric bidet use on the basis of the results of a questionnaire survey. In Japan, the frequency of electric bidet use is considered to be the same as that of toilet use, and this model is used by the Ministry of Economy, Trade and Industry (METI) in its official evaluation of equipment performance. However, in this survey, we found that 30–40% of respondents did not use electric bidets, even though they have become commonplace in Japan. The reason for this was a vague sense of anxiety about sanitation. Based on the results of the survey, the model for electric bidet use was set to once a day for men for flushing following defecation and once a day for women for either flushing following defecation or bidet flushing. This is considerably less frequent than the conventional Japanese electric bidet use model for women, which models for one flush following defecation and three flushes following urination. Japan's Energy Conservation Law requires improved energy efficiency in 32 items of equipment, of which the electric bidet is one. Because of this regulation, the electricity consumption of electric bidets has decreased by one fourth in the past 10 years. When a new model representing actual usage was applied, the environmental impact of the electric bidets currently sold was shown to be minimal. [ABSTRACT FROM AUTHOR]