This is a Guest Post by Islandboy
Non-Petroleum comments should be in this thread.
The EIA released the latest edition of their Electric Power Monthly on June 23rd, with data for April 2017. April data extends the milestones reached in March as follows:
- The contribution from solar reached 2.35%, up from 2%
- The contribution from All Renewables extended its lead over Nuclear by more than 2%
- The combined contribution from Wind and Solar reached 11%, up from 10%
- The contribution from Non-Hydro Renewables exceeded 13%, up from 12.24%
In addition the contribution of zero emission and carbon neutral sources, that is, nuclear, hydro, wind, solar, geothermal, landfill gas and other biomass reached its highest level over the period covered by the graph (January 2013 on) at 42.5 percent. This is likely to be another milestone, following the two previous months, during which the contribution from zero emission and carbon neutral sources was higher than the previous record month of March 2016 (41.3%).
Looking at the graph above, in all of the previous four years the contribution of All Renewables was at its peak in April with the exception of last year when it peaked in March. If the pattern holds for 2017 and wind and hydro output decline after April, it is unlikely that any increase in solar generation will be able to prevent the contribution from All Renewables from dipping back under 20% sometime between May and June.
The graph below shows the absolute output of all sources vs. total generation monthly from January 2013. The variation in the output for “Renewables Excluding Solar and Hydro” is largely attributable to variations in wind since, the output from geothermal sources, landfill gas and other biomass is relatively small and fairly constant throughout the year. Since the output from solar is also relatively small, the variation in the figures for Total Renewables is largely a result of the variations of wind and hydro. The way Total Renewables output varies in relation to the total from all sources results in a scenario where the contribution from renewables is greatest when total output is at its lowest in the spring and autumn.
The graph below shows the total monthly generation at utility scale facilities by year versus the contribution from solar. The left hand scale is for the total generation while the right hand scale is for solar output and has been deliberately set to exaggerate the solar output as a means of assessing its potential to make a meaningful contribution to the midsummer peak.
Since the previous edition of the Electric Power Monthly was released, the Solar Energy Industries Association released their latest Solar Market Insight Report 2017 Q2. The graph below shows that about 14.5 GW has been installed since March 2016, with about 4 GW having been installed in the third quarter of 2016 and about 6.5 GW in the last quarter. If one looks at the data for the first quarter of 2017, about 8.5 GW was installed in the six months up to the end of March 2017, somewhat supporting my suggestion that an unusually large increase in capacity may have occurred over that period. However, the size of that increase alone does not explain the steep ramp up of solar output between February and March and the increase between March and April appears far more modest. It may be that the shape of the output curve for 2017 has been influenced by weather. That would have to be confirmed by examining the output of plants that were commissioned before the beginning of 2016.
The graph below shows the monthly capacity additions for 2017 to date. In April over 79 percent of capacity additions were Natural Gas with Solar adding just under 14.5 percent. Wind contributed about 4.7 percent while Other Waste Biomass made a contribution of 0.7 percent. Batteries made up the remaining three quarters of one percent.