Renewable energy sources – solar, wind, biomass, geothermal and hydropower – accounted for nearly 18.0% of net domestic electrical generation during the first three quarters of this year, according to a SUN DAY Campaign analysis of newly released data from the U.S. Energy Information Administration (EIA).
In addition, the latest issue of EIA’s “Electric Power Monthly” (with data through Sept. 30) reveals that solar and wind both showed strong growth: Compared to the first nine months of 2017, utility-scale solar expanded by 30.3%, and wind grew by 14.5%. The growth in total solar – including distributed small-scale solar PV – was 28.2%, comprising a 30.3% increase in utility-scale solar and a 23.6% increase in small-scale solar.
Combined, wind and solar accounted for almost 9.0% of the nation’s electrical generation (wind at 6.4% and solar at 2.4%) and nearly half (49.7%) of the total from all renewable energy sources, according to the data.
Modest increases were also reported by EIA for geothermal and biomass: 5.4% and 1.5%, respectively. Taken together, non-hydro renewables, including distributed solar, grew by 14.9%. However, a 5.1% drop in hydropower output netted an increase of only 6.0% in electrical generation by all renewables in the first three quarters of 2018 compared to the same period in 2017, says SUN DAY.
Notwithstanding its lower production, hydropower remained the leading source of renewable electricity: It accounted for 7.05% of total electrical generation, followed by wind (6.41%), solar (2.42%), biomass (1.48%) and geothermal (0.39%).
The decline in hydropower, coupled with a 4.9% increase in total electricity produced by all sources (driven primarily by a 15.1% expansion of electrical production by natural gas and a 2.2% increase in nuclear power), resulted in renewables increasing their share of domestic electrical output only marginally – from 17.6% in 2017 to 17.8% in 2018, according to the data.
That modest gain, though, continued to close the gap between renewables and coal, with the latter dropping by 5.4%. Coal now provides 27.0% of the nation’s electrical generation compared to 30.0% a year ago. A decade earlier, coal’s share of U.S. electrical generation was over 48.0%, says SUN DAY.