PERTANIKA JOURNAL OF SCIENCE AND TECHNOLOGY

After the Great East Japan Earthquake, the household sector of public welfare is promoting the introduction of distributed energy systems by diversifying energy sources and applying local energy use as one of the energy supply measures in case of a disaster. This study introduced an energy-sharing system in the housing complexes to examine whether each house with different family composition and life patterns (i.e., different energy use patterns) could use energy more efficiently. The target energy in the housing complexes was set to electricity, which was generated by photovoltaic panels and stored in storage batteries. The strategy for stable electricity supply and profit generation was as follows: (1) electricity generated by photovoltaic panels is consumed first in the housing complexes; (2) the remaining electricity is stored in a large-capacity storage battery for the operation of the cooling and heating system; (3) afterward, electricity is sold directly to nearby housing complexes at a lower price than the supply price of electricity companies and at a higher price than when sold to electricity companies. The calculation results show that the profit from the sale of surplus electricity and the reduction rate of CO2 emissions were evaluated. The annual electricity purchase was 87 MWh, which decreased by 52% due to the introduction of the electricity-sharing system. Annual electricity sales were 433 MWh. The annual profit from selling surplus electricity directly to nearby houses was 1.14 times higher than selling to electricity companies. The CO2 emission reduction rate was 56.2%.

• Akisawa, A., & Takeshita, N. (2016). Optimal technical configuration of distributed energy system for apartment complexes considering energy supply maintenance during emergencies. Journal of the Society of Energy and Resources, 37(1), 1-8. https://doi.org/10.24778/jjser.37.1_1
  
  Iwata, T., Tanaka, K., Kato, D., Kimura, M., Matsuhashi, R., & Yamada, K. (2012). Study on estimation of hourly electricity consumption in residential sector in 2011 summer. Environmental Information Science Academic Research Papers, 26, 255-260.
  
  Korea Power Exchange (2019) Information on the electricity market. Korea Power Exchange. https://new.kpx.or.kr/board.es?mid=a10109010200&bid=0077&act=view&list_no=57652
  
  Kutsuki, R., Murakami, S. Sadowara, S., Ichikawa, T. Aosasa, K., Hasegawa, I., Yanai, T., Anna, F., & Mitsui, K. (2008). Research on improving the sustainability of city blocks through the widespread use of distributed energy systems. Architectural Institute of Japan Technical Report, 14(28), 497-502.
  
  Lee, S. (2019). Domestic and international smart city promotion trends and business feasibility analysis. Monthly Electrical Journal. http://www.keaj.kr/news/articleView.html?idxno=2511
  
  Lim, Y., Edelenbos, J., & Gianoli, A. (2019). Smart energy transition: An evaluation of cities in South Korea. Informatics, 6(4), Article 50. https://doi.org/10.3390/informatics6040050.
  
  Ministry of Economy Trade and Industry Japan. (2021). The purchase price is decided on, levy unit price, etc. for FY2021 under the FIT system. Ministry of Economy Trade and Industry, Japan. https://www.meti.go.jp/press/2020/03/20210324004/20210324004.html
  
  Ministry of Economy, Trade and Industry Japan. (2020). Energy white paper 2020. Ministry of Economy, Trade and Industry Japan. https://www.enecho.meti.go.jp/about/whitepaper/2020pdf/whitepaper2020pdf_2_1.pdf
  
  Ministry of Land, Infrastructure Japan. (2012). Regarding carbon.dioxide emissions and reductions related to houses and buildings. Ministry of Land, Infrastructure Japan. https://www.env.go.jp/council/06earth/y0614-03/mat02.pdf
  
  Nam., H. (2020). Impact of nuclear phase-out policy and energy balance in 2029 based on the 8th Basic Plan for long-term electricity supply and demand in South Korea. Renewable and Sustainable Energy Reviews, 122, Article 109723. https://doi.org/10.1016/j.rser.2020.109723
  
  Solar Power Association Japan (2020). Calculation committee materials. Solar Power Association Japan. https://www.meti.go.jp/shingikai/santeii/pdf/062_01_00.pdf
  
  The University Wisconsin Madison (n. d.) A transient systems simulation program. The University Wisconsin Madison. https://sel.me.wisc.edu/trnsys/
  
  Yuasa, K., Liu, Z., & Fujii, S. (2007). Research on the possibility of introducing distributed energy systems to apartment buildings. Proceedings of the Architectural Institute of Japan, Environmental Studies, 72(621), 51-56.
  
  Yuasa, K., Yu, S., & Wei, W. (2020). Energy interchange using fuel cell cogeneration in complex housing complexes. Architectural Institute of Japan Environmental Research Proceedings, 85(772), 485-493.