Dive Brief:

• Electricity generation by renewables ​(excluding hydropower) will grow 140% between 2012 and 2040 to reach 16% of the U.S. energy mix, according to the U.S. Department of Energy Energy Information Administration (EIA) Annual Energy Outlook 2014, but some renewables advocates claim that is a gross underestimation.
• Key factors that can significantly change its projections from its reference case of 16% by 2040, according to EIA, include assumptions about policy, demand growth, technology costs, and natural gas prices.
• If a policy putting a price on emissions is federally imposed, the EIA reports, renewables in the 2040 generation mix could be 83% higher, at over 27%, but if the U.S. turns to the use of more oil and gas, renewables could fall 12% below the 16% projection to just over 14% of U.S. electricity.

Dive Insight:

The EIA reference case 16% of electricity generation in 2040 projection puts renewables behind natural gas at 35% and coal at 32% but, if renewables policies are extended indefinitely or if a price is imposed on emissions, EIA projects that renewables would be over 16% of U.S. electricity by 2020.

Changes in EIA’s assumptions tend to lead to renewables penetrations above its reference case rather than below it, tend to affect long term projections more than short term projections, and tend to impact solar and wind more than biomass, waste, or geothermal generation.

Solar advocates at the Sun Day Campaign cite research showing that renewables will be 16% of the U.S. generation mix by 2018, based on the assumptions that (1) wind will grow from this year’s 4.5% of the mix to 5.5% by just 2016 and keep growing and (2) solar’s share of the mix, which grew 138% in 2012 and 114% in 2013, will continue to double at least through 2016.