Assessment of Software Lifecycle Energy and its Contribution to Green House Gas Emissions

This paper analyzes the total energy consumption associated with software production, delivery and use and assesses their contribution to green-house gas emissions. The results show that as software grows in size, the energy consumed at the production stage dominates the total lifecycle energy. However, if software is widely used, majority of the lifecycle energy is consumed at the use stage. For software as big as Linux 3.2 kernel, the total lifecycle energy exceeds 51GWh (equivalent of 31kilotons of CO2 emission). Reducing this environmental load requires energy-conscious software development and management.