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.

All this week, people the world over are celebrating Earth Week. Media headlines and social media feeds alike have been awash in coverage—what has changed since Earth Day 2018; things you can do to reduce your environmental footprint; urgent calls to action to do more, faster to avert the worst effects of climate change.

This year’s edition of Earth Week comes on the heels of sobering news. Late last month, the International Energy Agency (IEA) noted that in 2018 global energy demand rose 2.3% and worldwide energy-related carbon emissions rose 1.7%, the latter to their highest level ever. It’d be easy to despair and conclude doomsday climate scenarios are now inevitable. But at WattTime, the more deeply we look at the data, the more we’re starting to see an entirely different story emerging.

The game has changed—renewable energy is winning

It’s true that 2018’s numbers backslide slightly. But looking back in hindsight from a few year’s hence, we’ll likely soon conclude that 2018 was a minor speed bump in a larger story of rapid, powerful progress. We sit today on the precipice of a paradigm shift for the world’s electricity systems. Today, renewable energy accounts for over a third of global power capacity, per the International Renewable Energy Agency (IRENA). But it’s changing fast—both last year and the one before it, two-thirds of new electric generating capacity built worldwide was renewable, led by solar and wind.

The tides of the global energy system have already turned. Now we’re amidst the rush of its flowing waters, even if it hasn’t finished yet. It’s much like the camera market in the early 2000s. Digital cameras had just arrived on the scene. And while analog cameras still enjoyed majority market share and briefly looked strong, in reality they were just a few short years away from near-total extinction.

Granted, power plants don’t turn over as fast as consumer goods like cameras. But similar writing is on the wall. If you look at the power generation mix forecast from Bloomberg New Energy Finance’s New Energy Outlook 2018, it’s plain to see that we’re right at the threshold of a tidal shift that’s already begun. Coal, oil, and to a lesser extent natural gas are the analog camera equivalent; renewables are the shiny, new digital camera taking over the global market with impressive speed.

So what happens next?

The second renewable energy revolution: from generation hardware to timing software

In places where the renewable energy tides have advanced the furthest the fastest, we’re already seeing the need for new ways of thinking. Consider the case of California, which has more than 22.5 GW of installed renewable generating capacity. Over the past 3+ years, California has begun having moments of too much renewable energy, more and more frequently. In March 2019, California had to throw out or “curtail” a record 122,225 MWh of surplus solar and wind energy. Comparing Q1 2016 v2. Q1 2019 saw an incredible growth of 190% in California curtailment—all driven by a mismatch in timing, if people weren’t using energy at the same exact moments the wind was blowing or the sun was shining.

The world should and will continue installing more and more renewable energy generation—mostly solar panels and wind turbines. But scenarios like California’s strongly suggest that a second renewable energy revolution is on our doorstep. If the first revolution was about deployment of generation hardware, we’d argue the second revolution will be defined by the deployment of timing software.

Energy storage isn’t the (only) answer

Renewable oversupply like California is experiencing is generally—and rightly—considered a success story. We’ve deployed enough clean energy generation that at least in certain places, times, and/or seasons, we have even more renewable energy than we can use. But, obviously, if we are to continue adding more clean energy at the furious clip we need to stop climate change, the next step has to preventing that waste from growing and growing.

A common assumption is that energy storage (often, but not necessarily, batteries) is the solution. And, when deployed properly, storage can definitely help. But Earth neither has the time, nor even the need, for us to go out and buy billions of new batteries. Turns out, they’ve already been built! Literally tens of billions of smart devices in our buildings and on our roads—from thermostats to electric vehicles—are already deployed and have the physical hardware capable of soaking up excess renewable generation through smarter timing. As Rocky Mountain Institute and others have shown, flexible demand is a key, not-so-secret weapon. All it takes to give these devices such planet-saving capability is a software update.

Making ‘smart’ smarter with Automated Emissions Reduction

The final part of the equation is hidden in that word ‘smart.’ It’s used to describe everything from the latest generation of thermostats to grid-interactive water heaters to common appliances. But what does ‘smart’ really mean?

Here at WattTime, the definition is simple. A smart device is one that can be updated, now or later, to time its own energy consumption to run on clean energy. It’s capable of what we call Automated Emissions Reduction.So the next time you’re buying a smart light or a smart coffee machine that brews your cappuccinos on time, think about what else you’re really buying. Today, we think of that physical piece of hardware as a glorified toy. But this Earth Week, pause and appreciate that the massive proliferation of billions of such devices has also created the physical infrastructure for a global system to massively accelerate the growth of renewable energy and, before much longer, eliminate the need to ever use fossil fuels again.

It’s easy to see one bad year of news and get lost in despair. But if we want them to be, the days of fossil fuels are as numbered as analog cameras were not long ago.

If you could hold planet Earth in the palm of your hand, it would feel nearly as smooth as a billiard ball. Up close, features such as Mount Everest and the Marianas Trench become more formidable. An August 2018 McKinsey study on the how electric vehicles could impact demand on power grids showed a similar dichotomy between the big picture and the details in which the devil feels so at home.

Using a Monte Carlo simulation of EVs in Germany as a frame of reference, McKinsey researchers found that as EV adoption rises—from <1% of vehicle stock today to 7% by 2030 to 40% by 2050—EV-related electricity demand (kWh of consumption) would add just 1% to total German power demand by 2030 and about 4% by 2050.

So the big picture looks smooth and no cause for major alarm from a grid operations perspective. But EV adoption is unlikely to be uniform, and national averages will hide sharper geographic differences. Especially when it comes to suburban ‘hot spots’ where EV adoption is expected to be greatest.

In suburbia, surging EV demand could also spike grid demand

When the McKinsey team looked at postal-code-level EV penetration, it found that, in suburban areas where EV uptake is expected to be strongest, peak load would spike about 30% in the evening hours after commuters return from work and plug in their wheels.

That model, based on load profiles for a September day in the U.S. Midwest, assumed a typical residential feeder circuit for 150 homes, each home with two cars. One in four cars would be an EV charging at an average plug-in power of 3.7 kilowatts. Without corrective action, the analysists say, the associated 30% bump in peak demand would be enough to require grid upgrades costing several hundred dollars per EV to alleviate overloaded feeder circuits.

A second analysis considered the load profile of a fast-charging station. That one came back with more startling results yet. According to the authors, “a single fast-charging station can quickly exceed the peak-load capacity of a typical feeder-circuit transformer.” No surprise there, when one considers that a single EV using a high-end fast charger sucks as much juice as the peak demand of 80 households.

A role for coordinated EV charging and complementary strategies

Fortunately, there are solutions less formidable than scaling Everest or plumbing the depths east of the Mariana Islands. Among those the McKinsey team suggests include collocating an energy storage unit with the transformer (or, alternatively, pairing batteries with EV charging stations, as ChargePoint is doing with its PowerBlock fast-charging system).

The big one McKinsey suggests, though, is implementing time-of-use rates for electricity users. That at least provides a business case for load shifting in the form of a price signal for EV drivers to bulk shift EV demand from on-peak times to off-peak hours. But that still doesn’t solve the problem of myriad EV drivers all plugging in around the same time—even if at off-peak hours—and surging grid demand beyond what local circuits have been built to handle.

Moreover, for many grids across the country, existing time-of-use pricing doesn’t always correlate with grid emissions, so EV drivers could inadvertently be economically incented to shift their charging to times of higher grid emissions. We need to solve the demand-price-emissions equation as a set, rather than focus on one or two at the expense of the others.

To avoid dozens of EVs simultaneously draining the local grid during what would historically have been an off-peak time, doing this right will require “centrally coordinated, intelligent steering of EV-charging behavior,” the McKinsey team says. Or perhaps a blend of central coordination by utilities, distribution system operators, and EVSE network operators and decentralized coordination via EV drivers, automakers, and others at the grid edge.

Doing more with smart EV charging

Fostering smart EV charging behavior would offer myriad benefits, the authors say. Of course, it would shave peak demand at the heart of McKinsey’s study findings. Second, it would provide a new lever for managing system demand and offer valuable system-balancing services to grid operators (akin to a flavor of vehicle-to-grid services sometimes written about but not yet realized). And, it could crank up charging at times of high solar and wind generation (or, similarly, times of low marginal emissions rates) and ramp it back down when generation and marginal emissions get dirtier.

This last point is important. McKinsey is saying that centrally coordinated, smart EV charging done right should involve more than shaving peaks and taming the roller coaster of grid demand. It should take into account the mix of electricity being produced in a way that favors renewables over fossil energy sources, a need that will persist even as coal-fired electricity generation continues to wane. McKinsey has separately estimated that roughly 80 percent of the forecast growth in U.S. electricity demand is expected to be met with natural gas generation.

Here is where technologies such as WattTime’s Automated Emissions Reduction (AER) system can play a vital role.

It’s not hard to estimate average EV emissions based on overall grid mix in a particular region—calculators such as this one by the Union of Concerned Scientists can do that for you. But that’s like viewing Earth as cue-ball smooth; averages show a general picture but lack the details necessary for impactful decision making.

The electricity mix—and especially those generators that are on the margin—in a given locale varies minute-by-minute with the ebbs and flows of demand, winds gusting through turbine blades, clouds passing between solar panels and the sun, and so on.

Built into EVSE networks, EV chargers, and EVs themselves (or some combination), WattTime’s AER software keeps tabs on power generation and marginal emissions rates in real-time. That opens the door to the tracking marginal emissions of power consumption in fifteen-minute increments—and, more importantly, using that knowledge to optimize charging not only based on peak-load considerations, but also on the environmental impact of charging at a given moment.

There are, after all, counterintuitive times when it could actually better to charge an EV during times of peaking grid demand. For one example, imagine that peak demand aligns with a particularly windy day, where surplus wind generation is being curtailed. Or perhaps early afternoon on a late spring or early fall day, when solar PV is cranking but even the grid’s peaking demand isn’t enough to suck up all those sun-powered electrons. Normal time-of-use rates might push EV charging demand off peak and miss an opportunity to charge during that time of surplus wind or solar.

Without smart, flexible charging and the insights of technologies such as WattTime AER, peaks and troughs will be as ingrained in EV charging as they are in our planet’s crust. Fortunately, we have the tools to navigate the ups and downs in the cleanest possible way.