Technology improvement and emissions reductions as mutually reinforcing efforts: Observations from the global development of solar and wind energy

Mitigating climate change is unavoidably linked to developing affordable low-carbon energy technologies that can be adopted around the world. In this report, we describe the evolution of solar and wind energy in recent decades, and the potential for future expansion under nations’ voluntary commitments in advance of the 2015 Paris climate negotiations. Solar and wind energy costs have dropped rapidly over the past few decades, and commitments made in international climate negotiations offer an opportunity to support the technological innovation needed to achieve a self-sustaining, virtuous cycle of emissions reductions and low-carbon technology development by 2030. If countries emphasize renewables expansion, solar and wind capacity could grow by factors of 4.9 and 2.7 respectively between the present day and 2030. Based on future technology development scenarios, past trends, and technology cost floors, we estimate these commitments for renewables expansion could achieve a cost reduction of up to 50% for solar (PV) and up to 25% for wind. Forecasts are inherently uncertain, but even under the more modest cost reduction scenarios, the costs of these technologies decrease over time.