Exergy analysis on existing industrial gas turbine co-generation system was fulfilled. Compared to enthalpy analysis, the advantage of exergy analysis is to clearly grasp the irreversible change loss of the components and to prospect the system improvement. The results showed that the biggest exergy loss was found occurring in the combustor and adopting high compression ratio was effective to improve the combustor exergy loss smaller. Thus the latest gas turbine co-generation system gave high exergy efficiency above 50%. Detailed exergy analysis on hydrogen gas turbine and GRAZ cycle as hydrogen oxygen combustion cycle were also fulfilled. The result showed that merely alternating fuels from natural gas to hydrogen did not improve combustor exergy loss nor cycle exergy efficiency. Hydrogen oxygen combustion and hydrogen air combustion are almost equivalent form the point of combustion exergy loss. The advantage of GRAZ cycle as hydrogen oxygen combustion cycle was to improve combustion exergy loss by adopting higher combustion pressure and higher temperature combustor inlet working fluid.

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This paper empirically analyzes the relationship between refrigerator’s actual electricity consumption, its energy consumption efficiency (kWh/year), usage mode, and other various attributions using household-level data whose sample size is 232 households. Our result shows that refrigerator’s actual electricity consumption may decrease from 0.52% to 0.56% in response to a one percent improvement in its energy performance. According to this result, there is one possibility that an increase in refrigerator’s energy-efficiency can cut its actual electricity consumption by 26% in a household. Moreover, our estimation results suggest that the effort to save energy at household-level can play an important role in decreasing the actual consumption, and, therefore, it is significant that consumers obtain an adequate knowledge of further energy-saving.

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Fast demand response (DR) is expected to be one of the tools to mitigate power balancing challenges in the Japanese power system with high renewable energy integration. This report estimates the potential of reserve-type DR resources in Japanese industrial and commercial sectors based on our questionnaire survey results of 1589 respondents, which was conducted via mail for large-size industrial and commercial customers in the beginning of 2016. The results shows that, while a half of self-generators are likely to join reserve-type DR programs by increasing or decreasing their power outputs for a long duration and might provide promising reserve-type DR resources all through the year, only 20% might join the DR programs by shifting their load of production processes. Based on our estimation, available reserve-type DR with 1 hour ahead notification has the potential of 794±676MW for load creation and 776±517MW for load reduction, respectively, during 8:00-22:00 in spring and autumn, which are about 10% of the nation-wide required capacity of contingency reserve.

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