Five wind turbines a coal burning power plant in the background

Renewable energy beats coal for the first time (again)

 May 15, 2019 

As you read these words something incredible is happening throughout the United States: across the months of April and May, renewable energy is supplying more of the nation’s electricity than coal, according to estimates from the U.S. Energy Information Administration.

Make no mistake: this is another major milestone in the country’s energy transition. And this time next year, we expect even more of the same: renewable energy beating coal by a wider margin and for a longer period of time.

Even as we celebrate this as a “first” for the U.S., it joins a growing list of other, similar “firsts” that we’re hearing more and more.

Renewable energy keeps surpassing coal

The storyline has become increasingly common in recent years: renewables beating coal. This latest first—it turns out—is just the latest of many domestic and global examples:

In what feels like the ancient past of 2011, utility Xcel Energy—whose Colorado generation portfolio today still includes 44% coal, despite a sweeping shift in progress toward wind and solar—set a one-hour wind generation record, supplying 55.6% of demand with wind. Four years later, in 2015, Xcel set another record, supplying 54% wind power for an entire day.

Also in 2015, in Q2 the UK saw renewables overtake coal for the first time. The renewables-beating-coal motif has only strengthened there as the former gains momentum while the latter continues its drastic decline. In fact, in 2018 environmentalists and renewable energy advocates celebrated when the UK went 1,000 hours completely coal-free that year. And this year, the UK set a new record of 159+ continuous hours (6 days and counting) coal-free.

Meanwhile, in 2017 the entire EU—28 member countries—saw renewable generation surpass coal for the first time. While last year, Germany specifically saw renewables overtake coal for the first time.

As you might surmise, many other examples abound: from states such as Hawaii and California (where solar is leading the charge), to RTOs and ISOs like the Southwest Power Pool (where wind has begun to overtake coal).

With Automated Emissions Reduction, renewables can overtake coal faster and more often

Two key variables differentiate the various aforementioned renewables-beat-coal examples: a) the geographic extent (e.g., state, RTO/ISO, country, continent) and b) the duration of the time frame (e.g., an hour, a day, a week, a month, a year).

With some of these examples—and especially the U.S. EIA April-May numbers—there’s seasonal variation to take into account. For example, renewable generation tends to surge during spring (thanks to a seasonal bump from big hydro) while coal generation tends to sag during spring and fall (and rise during high-demand summer and winter periods).

This just goes to underscore the importance—sometimes significant—of timing.

Throughout the country, the electricity generation mix is constantly fluctuating. Solar ramps up during the day. Natural gas often ramps up in early evening as solar fades. Wind is often strongest overnight. In fact, the closer we look—with WattTime’s insights, all the way down to 5-minute increments—the more variation we see.

Inherent in that variation is the power to help renewable energy win vs. coal more often and by wider margins … if only we can harness that power.

How? By using software solutions such as Automated Emissions Reduction (AER) to shift flexible energy demand. AER allows any smart, energy-using device—from thermostats and HVAC systems, to refrigerators and electric water heaters, to batteries and electric vehicles—to sync their energy demand with times of clean energy while avoiding times of dirty energy.

Imagine the implications for the renewables-beating-coal storyline. Instead of surplus renewable energy being wasted through curtailment, we can shift our individual and collective energy demand to suck up that clean power, thus boosting renewable’s numbers. Conversely, we can actively avoid times when the dirtiest power plants (i.e., coal-fired) would run, further shrinking their numbers.

This is not a hypothetical scenario. The technology exists today. At a time when WattTime and partners are embarking on an exciting, bold project to monitor emissions from the world’s power plants, we can also leverage other WattTime technology to reduce those emissions and accelerate the renewable energy revolution.