戸建住宅における太陽光発電システムの導入者意識と発電実態

Residential photovoltaic (PV) systems are becoming increasingly popular. However, the satisfaction level of PV users has been scarcely studied, despite the fact that user satisfaction affects the future prospects of PV systems. Specifically, no research has been conducted on the influence of performance of PV systems on user awareness of these systems.In this context, we undertook a survey to look at the relationship between PV system user awareness and the performance of PV systems. The survey was conducted between December 2015 and January 2016 and included residents living in detached houses with PV systems. We received 571 valid responses, including 283 responses for annual power consumption and 183 responses for monthly power consumption. Followings are the main results of this study:· Users who recently installed PV systems tend to choose these systems for reducing their electricity bill and/or selling electricity. They were less likely to choose these systems for reasons of energy conservation/environmental protection and/or the enjoyment of generating electricity at home.· The overall user satisfaction rate is 90%, with 52% who indicated they were “satisfied” and 39% who indicated they were “relatively satisfied.” This demonstrates that most users have positive attitude towards PV systems.· Seventy percent of the following user groups indicated they are “satisfied” with PV systems: users who rated themselves as “very conscious” about saving power in everyday life; users who rated themselves as “very conscious” about choosing environment-friendly products and services; users who consider PV panels to “add to the beauty of their houses;” and users who have used a PV system's self-sustained operation more than twice during a power failure.· Users with a high overall satisfaction rate tend to be interested in increasing PV system capacity and driving electric or plug-in hybrid vehicles. We also found a statistically significant relationship between user satisfaction and using a personal electric or hybrid vehicle as a power source for a PV system. Furthermore, users with a high satisfaction rate have a greater tendency to recommend PV systems to others.· The average capacity of a PV system is 4.8 kilowatts (kW). The mode of photovoltaic power production is between 1,200 and 1,300 kWh annually. The PV system performance ratio, which represents power generation performance, is between 0.80 and 0.85 (n=283).· The percentage of generated power being used a