Historical and projected improvements in net energy performance of power generation technologies

Abstract

Renewable energy technologies are a key lever to mitigate climate change. However, net energy analyses showing low energy returns on energy invested (EROIs) for these technologies raise the question of whether current prosperity can be maintained with an increasingly renewables-dependent energy sector. Here we argue that static net energy analyses disregard the inherent potential to improve technologies through innovation. We present energetic experience curves for power generation technologies utilizing hard coal, solar irradiation, and wind, and show that EROI of new technologies improves as more capacity is installed. By 2015, solar PV and onshore wind were already outperforming coal, with further improvements to be expected. Therefore, concerns that a large-scale transition to renewable energy sources jeopardizes societal net energy efficiency and prosperity seem unfounded.