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.

Electric vehicles (EVs) are more efficient and less polluting than comparable rides powered by traditional internal combustion engines—even when EVs are charged on relatively dirty grids; plus, the greener that grids get with renewables, the cleaner EVs get with their associated emissions.

But there’s been the nagging question of whether, as sales continue to ramp up, EVs could become too much of a good thing for the power grid. For example, after 1.1 million new electric vehicles hit the roads globally in 2017, Bloomberg New Energy Finance forecasts that worldwide annual EV sales will hit 11 million by 2025 and 30 million by 2030. Can the electricity grid handle the coming wave of EVs and all the charging—some slow, some fast, and some superfast—that will come along with it?

A 2018 study from the UK’s Office of Gas and Electricity Markets (Ofgem) found reason for optimism—assuming that mass EV uptake comes hand-in-hand with intelligent charging systems. Ofgem found that “smart, flexible” charging solutions could allow at least 60% more EVs to connect to the existing UK power grid than would be the case without intelligent charging systems. With flexible fast charging, up to six times more EVs could connect, the authors found.

That’s possible, Ofgem says, because unlike inflexible EV charging—which blindly fills a big battery from the time it’s plugged in until it’s either topped off or the plug is pulled—flexible EV charging pays some attention to what’s happening beyond the outlet.

Charging flexibility makes all the difference

Inflexible EV charging, the authors say, increases peak demand, risks local outages, reduces system diversity, constrains areas that are already constrained, and forces all energy consumers to pay for new electrical infrastructure needed because of the added demand of EV owners.

Flexible EV charging, on the other hand, lowers the increase in peak demand, enables the more efficient use of existing assets, improves system diversity, defers or avoids power-infrastructure expansion, and can reward consumers—in pounds and pence (or dollars and cents, on this side of the Atlantic)—for their flexibility.

That’s a lot of cons and pros, but the big one has to do with peak demand. Depending on when peak demand occurs, and—more importantly—what power plants are called upon to meet that demand (often an expensive, polluting, fossil-burning peaker plant), there could be big implications for marginal grid emissions that risk casting a bit of a cloud over the clean EV story.

Keep in mind that the above doesn’t take into account vehicle-to-grid technology, which could harness EVs as a stored energy source, tapping into parked cars rather than peaking plants. For example, a Tesla Model 3 battery stores four to five times more electricity than a Tesla Powerwall battery. And overall, EVs that charge using a 240-volt outlet draw about as much power as six microwave ovens running simultaneously. Then imagine all that energy and capacity at coordinated scale. “As a pooled resource, the growing number of EV batteries could provide a wider range of valuable grid services, from demand response and voltage regulation to distribution-level services, without compromising driving experience or capabilities,” the Ofgem team explains.

How flexible charging unlocks greater grid value—while reducing emissions

Closer to home, the U.S. Department of Energy’s INTEGRATE study has estimated that with 3 million EVs—half of them using flexible charging and EV batteries as energy storage—peak demand would fall 1.5 percent. You read that right: adding 3 million electric cars could cut peak demand. Electricity costs would decline by 1 percent to 3 percent. In addition, renewable-energy curtailment would shrink by 25 percent and overall grid emissions could shrink, too.

That last bit about renewable energy curtailment and grid emissions is vitally important. Curtailment means wasting renewable energy that would otherwise be generated because the grid can’t accommodate it at a particular time.

Renewable energy’s contribution to the grid can change minute-by-minute. So, when we consider how to do smart, flexible charging of EVs for the optimization of power delivery, we should be asking not just if and how the grid can handle that demand but also what sources of generation are on the margin and/or at risk of curtailment at any point in time. In other words, how can smart, flexible EV charging help electricity grids from the UK to the U.S. not only handle more EVs but potentially do so while lowering their marginal emissions by charging at times of cleaner energy and avoid times of dirtier energy.

This sits squarely in the sweet spot of WattTime’s Automated Emissions Reduction (AER) technology. The software—including a recently updated EV charging module—uses a combination of real-time grid conditions and historical emissions data to track the precise mix of renewable and fossil energy coursing through a device such as an EV charger, in 5-minute increments.

This is especially important when it comes to EVs and marginal emissions. Yes, we can measure EV emissions based on overall grid mix in a particular region. But what arguably matters much more is marginal emissions. When I plug in my EV to charge (or unplug my EV to drive away), what power plant turns on or off in response to that demand? And can we ensure—through a combination of smart, flexible charging and the right signal, such as AER—that EVs are using as much clean energy as possible while avoiding dirty energy?

With the kind of smart, flexible charging envisioned in the UK Ofgem report and WattTime’s AER technology, the answer is yes. And that’s as big a story, we’d argue, as the UK grid being able to handle 60% more EVs.

The last quarter of 2018 saw the release of several major climate change reports that all came to similarly dire conclusions, reinforcing the call to action to decarbonize the global economy as deeply and rapidly as possible. One major lever for doing so comes down to two words: “electrify everything.”

The punchline is this: As the percentage of renewables powering our grid continues to grow, electricity generation becomes cleaner and, by default, so does everything that uses electricity, from transportation to buildings.

In a 2018 analysis, The Economics of Electrifying Buildings, nonprofit think-and-do tank Rocky Mountain Institute (RMI) took a closer look at the “electricity everything” concept, exploring the financial and carbon impacts of electrifying commonly fossil-fueled residential energy loads such as space and water heating. (Disclosure: WattTime is an RMI subsidiary.)

RMI’s deep dive accounts for several factors when weighing the potential economic and carbon impacts of electrification: the degree of demand flexibility, electrification’s applicability for new homes versus retrofits, differing utility rate structures across the country, the wide variability in seasonal temperatures and grid mix, for a few examples.

The report, which is worth the full read, ultimately concludes that electrification is the most cost-effective option for many, but not all, home space and water heating use cases. For example, in the most coal-heavy regions of the country, the switch is not yet beneficial. RMI expects that the outlook for many scenarios explored will improve in the near future, as more renewables come online and electric appliances become more cost-competitive.

Marginal emissions are the key to overall emissions reductions through electrification, especially for achieving deeper reductions sooner

Those coal-heavy dark shadows in the report serve as a reminder of the important practice of looking at marginal emissions when considering the effects of electrification: As we electrify more and more energy loads, we’re also, in theory, increasing demand on the grid and asking more power plants to “turn on” in response. These “marginal” plants — whether powered by solar, wind, natural gas, or coal — can produce wildly different levels of carbon emissions, which we refer to as “marginal emissions.” And it’s those emissions that must be considered as we analyze the impact of electrification in various regions and scenarios.

This topic sits at the center of WattTime’s expertise. Through our research, we’ve successfully illuminated where and how the grid sources electricity for marginal electricity demand at any moment of the day, and then quantified the resulting emissions. This data became the key underpinning to RMI’s electrification report.

Moreover, this understanding of marginal emissions is also the foundation of WattTime’s core technology, which makes smart devices even smarter. Our software sends a signal to grid-connected devices like smart thermostats and electric vehicles (EVs) to tell them exactly when to kick into gear to effortlessly choose times of cleaner over dirtier energy. This simple-yet-effective solution has become known as “Automated Emissions Reduction” (AER).

Electrification, demand flexibility, and AER can unlock a lower-carbon future

As investment in renewables advances at record pace and clean sources of energy function alongside dirtier options, the power of this duality is revealing itself. Thanks to solutions like WattTime’s and the growth of smart device alternatives, the option to “electrify everything” is more enticing by the day. With thermostats, EV chargers, refrigerators, and more, the argument that more electricity demand must equal more emissions becomes invalid if and when a solution like AER is used. 

While it’s true that widespread energy efficiency upgrades will also play an important role in our progress toward emissions reductions, we cannot afford to ignore the opportunity presented by electrification, demand flexibility, and AER technology. These three pieces of the puzzle can work hand in hand to effortlessly, seamlessly, and automatically reduce emissions and move us closer to our decarbonization goals.

WattTime is proud to support important research in the cleantech space that will further enable our electricity grid’s monumental transition away from fossil-fueled energy. Every day we strive to give power to people and businesses that want the option to use cleaner energy. By partnering with innovators at like-minded organizations like Rocky Mountain Institute, we can work together to allow energy users worldwide to make a complicated choice much simpler.