Renewable energy: past trends and future growth in 2 degrees scenarios

This study explores past growth rates of renewable energy sources (1971-2012) and required future ones in 2 degrees scenarios. Results show that in spite of comparatively high growth of renewable energy in the period 2000-2012, the share of renewable energy in total energy use stayed the same (13%). The overall increase in renewable energy amounted to 2.2%/yr in the period 1971-2012 and 2.6%/yr in the period 2000-2012. In order to be consistent with a 2 degrees pathway the growth rate would need to increase to 3-5%/yr. Especially high growth would be required for wind, solar and geothermal (∼10%/yr). This would lead to a change in the mix of renewable energy used, with a much higher share of variable renewable energy sources. However most notable is the strong difference in the growth of energy use, compared to past trends. Primary energy use needs to consistently decrease by 0.1-0.5%/yr for OECD regions, up to 2050, which would require a breach from past trends. But especially for non-OECD regions the needed change is large. Regional growth rates for energy use in the period 2000-2012 range from 1.5%/yr to 6.1%/yr and should decrease to the range of -0.2%/yr to 0.9%/yr.