Renewables Crushing Coal — Won 100 Days Already In 2020 (USA)
Originally published by Union of Concerned Scientists.
by John Rogers, Senior energy analyst
If you need some good news at a time when there’s plenty of the less-good sort, try this: Renewable energy is crossing some really important milestones in its contribution to the US power sector. The latest involve its generation relative to coal’s: A year-to-date performance for renewables that is dramatically above any previous year’s, and a streak going on right now that hints at where our electricity supply needs to head, with renewables overtaking fossil fuels day by day.
Here’s why we’re hitting those milestones. Plus some important next steps — for keeping the transition going, and making sure everybody has an opportunity to be part of the change.
Renewables are Beating Coal
First, the data. Last month, the research institute IEEFA reported that renewables had generated more than coal every day in April. Numbers from a new tool from the US government’s Energy Information Administration (EIA) show that the trend has continued.
Here’s what the data say:
- As of last Friday, May 21, we had hit 100 days in 2020 in which renewables have beaten coal. That’s more than two and half times as many days as in all of 2019 (38), and 70% of the days so far this year.
- Nestled in that first milestone is another one: Renewables had also beaten coal for 60 days straight (and was still going). In 2019, the longest streak was 9 days long.
- The daily ratios of renewables to coal have also changed impressively: While in 2019 the best day saw renewables generating 154% as much electricity as coal, already in 2020 we’ve seen more than two dozen days above that 154% level, and as high as 196% (that is, almost twice as much renewable energy as coal).
Here, in black and white, is what that all looks like on a daily basis (2019, and 2020 to date, with each black stripe indicating a day where coal bested renewables, and white indicating a renewables-on-top day):
Note the early advent this year of the white lines, the acceleration of their frequency as spring neared, and, of course, the unbroken streak up to today.
Here’s another way of looking at the data, showing the difference between coal and renewables generation, with black indicating when coal was higher, and blue showing renewables-heavy days:
Several missing pieces in these EIA data would each make the numbers even more impressive for renewables. The dataset is just for the contiguous 48 states; in both Alaska and Hawaii renewables have been handily beating coal every month for at least the last few years. “Renewables” in the data used for these calculations include wind, solar, and hydro — the three largest renewable sources, sure, but not the whole picture. For solar, EIA’s dataset doesn’t include small-scale systems, including rooftop solar, which is an increasingly important omission; in 2019, those systems accounted for a third of solar generation. The output from just those two missing pieces (early data here) would have bumped up the year-to-date tally by maybe a dozen days.
Why are Renewables Beating Coal?
So why is this happening? Coal and renewables’ changing fortunes stem from several different factors, peculiar to this moment, seasonal, or long term.
Demand is down. One factor has to do with the COVID crisis, and what it has done to our economy. Having factories, shops, and offices closed has meant a substantial drop in electricity demand, and the extra residential electricity use from stay-at-home orders hasn’t made up for that.
Our electricity demand gets met (generally) by using — “dispatching” — first the sources that are cheapest to operate, then more expensive stuff, then, for any peaks, the most expensive. Sources with no fuel costs — think wind, solar, and hydro — make the most sense to use first. Sources that require fuel (= cost) come later, and, when demand is lower, don’t necessarily even make the cut.
Since coal is far from the cheapest source these days, it’s increasingly in that stay-on-the-sidelines category.
Spring is good. Another factor at play in renewables’ strong performance is that spring is a good time for the sources in question. Wind is flourishing, hydro is nourished by snowmelt and spring rains, and solar is loving the approach of the summer solstice. Coal is also generally needed less as heating needs decline.
Renewables have been gaining. The biggest factor in this reversal of fortunes, though, is two really important long-term trends: Coal has been losing ground, and renewables have been gaining, for years.
Coal’s generation in January and February, for example, was down 36% and 31%, respectively, from the same months the year before, according to those EIA figures. Large solar, meanwhile, generated 17% and 32% more in those months, and wind was up 10% and 15%. Other, more inclusive EIA data shows even stronger gains by wind and, with smaller solar included, shows February-to-February solar overall up almost 40%. (Even accounting for the Leap Day.)
Note that January and February were before the COVID crisis had become a noticeable factor in this country’s energy use.