Evaluation of the feasibility of distributed energy supply system for existing multi-family housing in Nagoya City

Abstract

The possibility of introducing distributed energy system consisting of combining heat and power generation (CHP) for existing multi-family housing is discussed in order to make an academic ground for calling for the spread of distributed energy systems in existing multi-family houses. Case study was conducted to evaluate energy conservation effect of the distributed energy supply system and obtain the findings concerning on its feasibility. The case study was focusing on all municipal multi-family housing in Nagoya city, Japan, and it was evaluated based on primary energy consumption reduction, CO2 emission reduction, simple pay-back period, and recurring expenses merit by introducing the system. Annual energy consumption was estimated for nine typical municipal multi-family houses with different average occupied floor area and number of dwelling for each individual building unit. Based on the results of the case study, it was found that the effect of the distributed system varies depending on the average occupied floor area and the number of residences, and the generator capacity of CHP. In addition, when assuming adapting a distributed energy supply system into a type of housing has occupied floor area of 30m2-50m2 per a dwelling that accounts for 83.5% of the total municipal housing in Nagoya, at least the overall reduction of 16.7% CO2 emission reduction rate could be expected.