Abstract
For expanding the installation of solar power systems in detached houses, it is important to understand the status of power consumption and solar power generation based on their characteristics. Therefore, we surveyed the electricity consumption, PV capacity, power generation, power sales, and self-consumption rate of detached houses in each year of PV installation, using micro data of survey on carbon dioxide emissions from residential sector. The results show that the average capacity of PV installed before 2010 was 3.9 kW, while the capacity of PV installed in 2013-2014 was 5.5 kW, an increase of more than 30%. On the other hand, it was found that the total floor area of houses has not changed that much. Thus the increase in average PV capacity can be attributed to lowered economic constraints such as reduced PV system costs and the popularity of overloading. In addition, there has been no increase in average capacity of PV installed after 2015, which can be due to new constraints related to the location of PV installations, such as the total floor space of houses.
