CO₂ Payback Time and Reduction Effect of CO₂ Emission Originated from Electricity of Detached Household by Introducing DC LED Lighting System Utilizing Photovoltaic Power Generation and Storage Battery

Abstract

This study evaluated the lifecycle reduction potential and the payback time of CO₂ originated from general detached household electricity consumption by introducing the DC LED lighting system utilizing photovoltaic power generation and storage battery. Among various DC LED lighting systems, the system with storage battery capacity adjusted to night lighting power demand showed relatively high CO₂ reduction potential. In the system with storage battery capacity extended to whole daytime surplus power generation, shortening of battery lifetime caused by repeated complete discharge should affect lifecycle CO₂ increase of the system. The CO₂ payback time of DC LED lighting system varied between 1.5 and 2 years according as several regional characteristics such as electrical grid CO₂ emission factor, photovoltaic power condition and storage battery lifetime related to the required capacity.