electric grid

Wind and solar power generators wait in yearslong lines to put clean electricity on the grid, then face huge interconnection fees they can’t afford

Posted on by abrahamwien18

By: Catherine Clifford
View the original article here

Heavy electrical transmission lines at the powerful Ivanpah Solar Electric Generating System, located in California’s Mojave Desert at the base of Clark Mountain and just south of this stateline community on Interstate 15, are viewed on July 15, 2022 near Primm, Nevada. The Ivanpah system consists of three solar thermal power plants and 173,500 heliostats (mirrors) on 3,500 acres and features a gross capacity of 392 megawatts (MW).
George Rose | Getty Images News | Getty Images

Wind and solar power generators wait in yearslong bureaucratic lines to connect to the power grid, only to be faced with fees they can’t afford, forcing them to scramble for more money or pull out of projects completely.

This application process, called the interconnection queue, is delaying the distribution of clean power and hampering the U.S. in reaching its climate goals.

The interconnection queue backlog is a symptom of a larger climate problem for the United States: There are not enough transmission lines to support the transition from a fossil fuel-based electric system to a decarbonized energy grid.

Surprise fee increases

The Oceti Sakowin Power Authority, a nonprofit governmental entity owned by seven Sioux Indian tribes, is working to build 570 megawatts of wind power generation to sell to customers in South Dakota.

“Economic development through renewable energy speaks to the very heart of Lakota culture and values – being responsible stewards of Grandmother Earth, Unci Maka,” Jonathan E. Canis, general counsel for the Oceti Sakowin Power Authority, told CNBC. “Together our tribes occupy almost 20% of the land area of South Dakota. And the experts who have been measuring our wind resources literally describe them as ‘screamin.’.”

To connect wind power generation to the electric grid and make money from the sale of that power, the Oceti Sakowin Power Authority — like every electricity generator in the U.S. — has to submit an application called an interconnection request to whichever organization is overseeing the coordination of the electric grid in that region. Sometimes it’s a regional transmission planning authority, other times a utility.

This photo shows the rangeland on the Cheyenne River Reservation with the Missouri River in the distance. The Oceti Sakowin Power Authority wants to build two wind power projects and the Ta’teh Topah project, planned to be 450 megawatts, is the larger of two wind projects. The transmission tie-line for the Ta’teh Topah project will cross the rangeland and the river to interconnect with a Basin Electric transmission line east of the Missouri River.
Photo courtesy Oceti Sakowin Power Authority.

In late 2017, the Oceti Sakowin Power Authority paid a $2.5 million deposit to secure a place in line for its application to be reviewed by the Southwest Power Pool, a regional grid operator.

Five years later, in 2022, the Southwest Power Pool came back and told it that the fee to connect to the grid would actually be $48 million. That’s because connecting all that new power to the grid would require major updates to the transmission infrastructure.

The Oceti Sakowin Power Authority had 15 business days to come up with the extra $45.5 million.

“Needless to say, we couldn’t do it and had to drop out,” Canis told CNBC.

Now, the Oceti Sakowin Power Authority is reevaluating the size and composition of the project and plans to reenter the interconnection queue by the end of the year. That could mean another yearslong wait in line.

These burdens are typical.

In 2020, Pine Gate Renewables had a solar project located in the Piedmont region of North Carolina that it expected to cost $5 million to connect to the electric grid. The local utility in charge of overseeing the interconnection process told Pine Gate it would be more than $30 million. Pine Gate had to terminate the project because it couldn’t afford the new fees, its vice president of regulatory affairs, Brett White, told CNBC.

“We view, as a company, the interconnection problem as the biggest impediment to the industry right now and the costs associated with interconnection are the biggest reason that a project dies on the vine,” White said. “It’s the biggest wild card you have going into the project development cycle.”

There are efforts underway to improve the efficiency of the process, but they’re fundamentally putting a Band-Aid on top of an even deeper problem in the United States: There isn’t enough transmission infrastructure to support the energy transition from fossil fuel sources of energy to clean sources of energy.

“You could make the process for the queue as efficient and pristine as possible and it still could not be all that effective because at some point you’re going to run out of transmission headroom,” Wood Mackenzie analyst Ryan Sweezey told CNBC.

This photo shows the Western Area Power Administration’s substation in Martin South Dakota on the Pine Ridge Reservation where the 120 megawatt Pass Creek project, the smaller of the two wind power projects Oceti Sakowin Power Authority is trying to stand up, will interconnect if the project can move forward.
Photo courtesy Oceti Sakowin Power Authority.

Waiting in line

The entire electric grid in the U.S. has installed capacity of 1,250 gigawatts. There are currently 2,020 gigawatts of capacity in the interconnection queue lines around the country, according to a report published Thursday by the Lawrence Berkeley National Laboratory. That includes 1,350 gigawatts of power capacity, mostly clean, looking to be constructed and connected to the grid. The rest, 670 gigawatts, is for storage.

In 2022, the active energy capacity in interconnection queues in the U.S. is about 2,020 gigawatts and exceeds the installed capacity of entire U.S. power plant fleet, which is about 1,250 gigawatts, according to the report on interconnection queues out of Lawrence Berkeley National Laboratory published Thursday.
Chart courtesy Joseph Rand at Lawrence Berkeley National Laboratory.

Berkeley Lab pulls interconnection queue data from all of the regional planning territories in the United States and from between 35 and 40 utilities that are not covered by areas with regional planning authorities. The data covers between 85% and 90% of the electricity load in the United States, Joseph Rand, an energy policy researcher and the lead author of the study, told CNBC.

The interconnection process starts with a request to connect to the grid, which officially enters the power generator in the interconnection queue. The next step is a series of studies — the feasibility, system and facilities studies — where the grid operator determines what equipment or upgrades will be necessary to get the new power generation on the grid and what it will cost.

If all the parties can agree, then the power generator and grid operator reach an interconnection agreement, which establishes the grid improvements the power generator will pay for.

The total power capacity that comes out from a fossil fuel-burning power plant is often much greater than the capacity from renewable plants. That means it can take multiple wind or solar power generation plants — and, therefore, interconnection requests — to get the same units of energy online.

A single natural gas plant could be 1,200 megawatts, Sweezey told CNBC. “That’s one request — 1,200 megawatts,” Sweezey said. “Whereas usually if you’re going to get that same amount of capacity with renewables, that’s going to be six, seven, eight, nine, 10 different projects. So that’s 10 different requests in the queue.”

On average, it took a new power generation project 35 months to go from the interconnection request being filed with a grid operator to an interconnection agreement being reached in 2022, according to Berkeley Lab.

The amount of electricity generation in queues by region by type of power, according to the report on interconnection queues out of Lawrence Berkeley National Laboratory published Thursday.
Chart courtesy Joseph Rand at Lawrence Berkeley National Laboratory.

How did this process become such a problem?

The U.S. energy grid is a patchwork system of many regional utility companies. Some provide transmission services and some don’t.

In an effort to promote competition, the Federal Energy Regulatory Commission issued an order in 1996 saying transmission service has to be provided to power generators on a nondiscriminatory basis. This allowed all kinds of power generators, including those that do not own transmission infrastructure, to compete. In 2003, it issued another order that standardized the interconnection process for energy generators.

Both orders “attempted to make the services one needs nondiscriminatory and fair to all users, for their respective service,” according to Rob Gramlich, founder of transmission market intelligence firm Grid Strategies.

This is a simplified visualization of the interconnection queue study process.
Chart courtesy the Government Accountability Office and Lawrence Berkeley National Laboratory.

That process worked well enough when the power generation industry was building large, centrally located energy plants that burned fossil fuels. But the process started to show signs of strain around 2008 when renewable energy started to come online in places where there was not sufficient transmission, Gramlich told CNBC. In April 2008, MISO, one of the regional operators, said it would take 42 years, until 2050, for it to get through its interconnection queue.

Reforms in 2008 and 2012 helped a little bit, Gramlich told CNBC. “But I think everybody’s realizing now that that original process is fundamentally unsuited to the new generation mix.”

The interconnection process is especially bad at estimating battery storage, said White. That’s because transmission planning is always defaulting to the worst-case scenario, but batteries will draw energy from the grid when the demand is low and energy prices are low, and then use that stored power when the grid is at or near capacity. Using worst-case-scenario planning for battery storage fundamentally misses the point of a battery.

“The upgrades that are going to be triggered on the system are going to be very, very extensive and very, very expensive. And so they hand you a bill that reflects that,” White told CNBC.

But that kind of system upgrade “in our mind is totally disassociated from the economics of the asset, and not really looking at the benefit that the project is going to provide to the system,” White said.

Texas makes it easier

The rates of interconnection applications that actually reach commercial completion vary significantly, but none are higher than 38% in the New England region, according to Berkeley Lab. The Texas grid operator, Electric Reliability Council of Texas, or ERCOT, has a completion rate of 31% and is the only other region with a completion rate of over 30%.

On the low end, the California Independent System Operator region has an 13% completion rate and the New York Independent System Operator region is at 15%.

This chart shows the share of projects that requested interconnection from 2000 to 2017 that have reached a commercial operation date.
Chart courtesy Joseph Rand at Lawrence Berkeley National Laboratory.

The low percentage of interconnection requests that actually get built is partly because of the high cost to connect.

In the MISO region, for instance, interconnection costs were generally less than $100 per kilowatt-hour from 2008 to 2016, but have risen to a few hundred dollars per kWh for wind and solar, with spikes as high as $1,000 per kWh in some parts of the region, Gramlich told CNBC.

Adding even small amounts of energy to the grid requires infrastructure improvements because it’s nearly at capacity. Pushing those costs onto the builders of individual renewable projects generally makes them economically unsustainable.

“Those projects ended up withdrawing from the queue or terminating, because they don’t pencil anymore,” White told CNBC.

Some of the completion rates are artificially low because developers don’t actually expect to complete them all, but instead shop the same project around to various regional grid operators to get the best deal — what’s called “speculative queuing,” Sweezey told CNBC. It’s not expensive to get into queues, so developers submit applications to get information about which location will require the least expensive upgrades.

For grid operators, having power generators stuff their queues is overwhelming an already taxed system.

“Projects that have come through the process are not being built and becoming operational,” Jeffrey Shields, a PJM Interconnection spokesperson, told CNBC. “There are about 38,000 MW of renewable projects that have no further PJM requirements but are not being built because of siting, supply chain, or other issues facing the industry that are not related to PJM’s interconnection process.”

The long application timelines and expensive upgrades have made Texas a desirable place to build renewable energy projects because the state has its own interconnection application process.

“There is Texas, and then there’s the rest of the country with respects to interconnection,” White of Pine Gate told CNBC. Texas doesn’t require the same level of network upgrades to get power generation connected to the grid so getting a project online in Texas is faster and lower cost than the rest of the country, White said.

“You can put a project in the PJM queue tomorrow and it may not get constructed and built until 2030, whereas if you do the same with the Texas project, right now, it’s probably online in two to three years. So it’s just a much, much shorter timeline to commercial operation for a project in Texas,” White told CNBC.

But Texas also has a unique risk because ERCOT can decide to limit the amount of power that a generator can sell to the market if a particular electric corridor gets overly congested.

“It’s a bit of a double-edged sword,” White told CNBC. But with infrastructure deals, “time kills deals, time kills projects,” White said, so energy developers may prefer to take the risk and get the deal done.

Huge clouds and transmission towers are seen from Highway 5 in Kern County of California, United States on April 2, 2023.
Anadolu Agency | Anadolu Agency | Getty Images

How does this situation get fixed?

In June 2022, FERC issued a proposal on interconnection reforms to address queue backlogs and has since received a slew of public comments.

“We understand that 80 to 85 percent of the projects that are waiting in the queue ultimately are not being built. I think FERC has an opportunity here to make sure that we unlock that bottleneck and that we do all that we can to move those projects forward,” FERC Chairman Willie Phillips said on March 16, according to a statement provided by a FERC spokesperson.

The proposed rule change would offer incremental improvements, like providing information to developers so they can make more informed siting decisions without flooding the queue with speculative requests, and imposing more strict mandates on the regional grid operators to complete studies in a given time period, Rand of Berkeley Lab told CNBC.

“I do think what FERC is proposing has the potential to improve this situation,” Rand told CNBC. But fundamentally, these iterative changes won’t be a silver bullet.

“The energy transition is here. But our updating and expansion of our electric transmission system so far has not even remotely kept pace with that velocity, rate of change we are seeing on the generator-supply side,” said Rand.

There’s also a shortage of the kinds of electrical and transmission engineers required to process all of these applications, Sweezey and White told CNBC. “There’s just not enough people and so we have to think about what is the smartest way to maximize that expertise. And that means getting those engineers out of some of the rote manual data entry and into the actual analysis,” White told CNBC.

Another option is building new sources of clean energy that can be constructed closer to where demand is needed, like small nuclear reactors, Sweezey told CNBC. “I just don’t think people have come to that realization yet.”

Building sufficient transmission to support the energy transition is not necessarily a technical challenge as much as it is a political one.

“The type of coordination and planning that’s required for this kind of large-scale transmission — this involves maybe multiple utilities, multiple grid operators, multiple states, cities, counties, everything, even the feds are all involved — and that is antithetical to the U.S. as structured as a decentralized nation,” Sweezey told CNBC.

But the stakes are high.

“Even with all of the work, with all this great stuff that’s in the IRA and all of the wind that is in the sails of decarbonization in the renewable industry, if you can’t address transmission and infrastructure, then those goals aren’t going to be met,” White told CNBC.

“It really is the bottleneck that’s preventing that from happening.”

Geothermal energy could be off-ramp for Texas oil

Posted on by abrahamwien18

By: Saul Elbein
View the original article here

AUSTIN, Texas — Four years of drilling for energy deep underground would be enough to build Texas a carbon-free state electric grid, a new study by an alliance of state universities has found. 

The state’s flagship universities — including the University of Texas at Austin, Rice University and Texas A&M University — collaborated with the International Energy Agency to produce the landmark report.  

It depicts the Texas geothermal industry as a potential partner to the state’s enormous oil and gas sector — or an ultimate escape hatch.  

In the best case, the industry represents “an accelerating trend” that could replicate — or surpass — the fracking boom, said Jamie Beard of the Texas Geothermal Entrepreneurship Organization at the University of Texas.

“Instead of aiming for a 2050 moonshot that we have to achieve some scientific breakthrough for — geothermal is deployable now,” Beard said. “We can be building power plants now.”

The authors stressed that the geothermal, oil and gas industries all rely on the same fundamental skillset — interpreting Texas’s unique geology to find valuable underground liquids.  

In this case, however, the liquid in question had long been seen as a waste product: superheated water released as drillers sought oil and gas.   

About “44 terawatts of energy flow continually out of the earth and into space,” said Ken Wisan, an economic geologist at the University of Texas.

“Rock is a great heat battery, and the upper 10 miles of the core holds an estimated 1,000 years’ worth of our energy needs in the form of stored energy,” Wisan added. 

Most of the state’s population lives above potentially usable geothermal heat — as long as there’s a will to drill deep enough.  

Superheated trapped steam that is nearly 300 degrees Fahrenheit — the sweet spot for modern geothermal — is accessible about three to five miles below the state capital of Austin and 2 1/2 to 3 miles beneath its most prominent city of Houston, the report found. 

The report casts geothermal energy as a possible way out of two energy paradoxes. 

The first concerns the state’s beleaguered electric grid. The isolated system has been repeatedly driven nearly to the point of blackouts by extreme heat and cold, as well as the relentless, demanding growth of the state population. 

According to the Energy Information Agency, the state’s substantial renewable potential is meeting part of this growth: Texas leads the nation in wind energy and has near-leading solar potential.  

But the Republican-dominated legislature has been anxious over how to establish “baseload” power — the minimum demand of the grid — as well as readily “dispatchable” energy resources. 

Several state Republican leaders and the state Public Utility Commission have pushed for the construction of new coal, natural gas and nuclear plants to provide round-the-clock power.

Despite their different forms, these “thermal” options rely on the same fundamental trick. Whether powered by coal or uranium, most modern power plants use the fuel boiling water to create steam, which spins an electromagnetic turbine, creating an electric current. 

Geothermal offers another cheaper and more climate-friendly solution: start with steam, which exists in superheated pockets miles below the earth’s surface. 

Rebuilding the state a power system on a base of geothermal energy would give “the same performance as gas, coal or nuclear” at a lower cost, said Michael Webber, a professor of clean energy at the University of Texas. 

But Webber said it would also do so “without the same fuel reliability problems.”

During Texas’s February 2021 winter storm, Webber noted, natural gas and coal supplies froze — which wouldn’t have been a problem with geothermal.  

The industry also gives Texas a means of transitioning its flagship industry off planet-heating products like oil and gas. 

The International Energy Agency declared in May 2021 that for the world to meet global climate goals, new oil and gas production would have to cease, as The Hill reported. 

Since that warning, global oil and gas production has continued to increase — and is on track to hit record levels in 2023. But Tuesday’s report, which the global energy watchdog helped produce, suggested that geothermal energy could be a politically palatable offramp for the industry.  

The report found that if the Texas drilling industry drilled as many geothermal wells as it currently does oil and gas, about 15,000 per year, the state could run itself off geothermal power by 2027.

Webber said that would free up natural gas to replace more carbon-intensive coal in other locations, from Indiana and West Virginia to India and China.

With Texas’s needs at home met by cheap geothermal, “oil and gas would have more molecules to sell to other people probably for more money,” Webber added.

Beard said that the oil and gas industry offers a potential model for how the geothermal industry could rapidly expand

“The very beginnings of oil and gas, they were picking up oil and gas off the surface of the ground and puddles,” she said, in an analogy to the geothermal industries in highly geologically active Iceland, with its frequent eruptions. 

But eventually, the fossil fuel industry began to drill and advance. “And then sure enough, now we’re drilling in 5,000 feet of water offshore with billion-dollar, technically complex wells,” Beard said. 

“And that is what we could do for geothermal, right?” she said. “We could go for the deepwater of geothermal, and we can do it in the next few decades.

Are Electric Cars Truly Better for the Environment?

Posted on by abrahamwien18

Looking at the whole life cycle of EVs, the verdict is clear.

Looking at the whole life cycle of EVs, the verdict is clear.
Written By: David M. Kuchta
View the original article here.

Are electric vehicles truly better than gas cars for the environment? Not in all facets or in all regions of the world, but overall, unquestionably, yes—and as time goes on, only more so.

While much clickbait has been written questioning the environmental superiority of EVs, the cumulative science confirms that in almost every part of the world, driving an EV produces fewer greenhouse gas emissions and other pollutants than a gas-powered car. The internal combustion engine is a mature technology that has seen only incremental changes for the past half-century. By contrast, electric vehicles are still an emerging technology witnessing continual improvements in efficiency and sustainability, while dramatic changes in how the world produces electricity will only make electric vehicles cleaner.

“We still have a long way to go, and we don’t have the luxury of waiting,” said David Reichmuth of the Union of Concern Scientists in a recent interview with Treehugger.1

The transportation sector generates 24% around the world and 29% of total greenhouse gases (GHG) emissions in the United States—the largest single contributor in the U.S.2 According to the EPA, the typical passenger vehicle emits about 4.6 metric tons of carbon dioxide per year at an average of 404 grams per mile.3 Beyond carbon emissions, road traffic from gas-powered vehicles generates fine particulate matter, volatile organic compounds, carbon monoxide, nitrogen oxides, and sulfur oxides, the adverse health effects of which—from asthma and heart disease to cancer and pregnancy disorders—have been well demonstrated and disproportionately impact low-income communities and communities of color.4 EVs can’t solve all those problems, but they can make our world a more livable place.

Life-Cycle Analysis

The key to comparing gas-powered vehicles with electric ones is life-cycle analysis, which accounts for the entire environmental impact of vehicles from the extraction of raw materials to the manufacturing of vehicles, the actual driving, the consumption of fuel, and their end-of-life disposal.

The most significant areas of difference are in the upstream processes (raw materials and manufacturing), during driving, and in fuel sources. Gas-powered vehicles are currently superior when it comes to resources and manufacturing. EVs are superior when it comes to driving, while the issue of fuel consumption depends on the source of the electricity that fuels EVs. Where the electricity supply is relatively clean, EVs provide a major benefit over gas-powered cars. Where the electricity is predominantly coal—the dirtiest of the fossil fuels—gas-powered cars are less polluting than electric vehicles.

But coal is less of a major source of electricity around the world, and the future favors EVs fueled by clean energy. In two comprehensive life-cycle studies published in 2020, the environmental superiority of gas-powered vehicles applied to no more than 5% of the world’s transport.5 In all other cases, the negative impacts of upstream processes and energy production were outweighed by the benefits of a lifetime of emissions-free driving.

In the United States, given the decreasing reliance on coal in the electricity grid, “driving the average EV is responsible for fewer global warming emissions than the average new gasoline car everywhere in the US,” according to Reichmuth’s recent life-cycle analysis for the Union of Concerned Scientists.

As Nikolas Hill, co-author of a major 2020 study for the European Commission, told the podcast How to Save a Planet: “It’s very clear from our findings, and actually a range of other studies in this area, electric vehicles, be they fully electric vehicles, petrol-electric, plug-in hybrids, fuel cell vehicles, are unquestionably better for our climate than conventional cars. There should be absolutely no doubt about that, looking from a full life-cycle analysis.”

Raw Materials and Manufacturing

Currently, creating an EV has a more negative environmental impact than producing a gas-powered vehicle. This is, in large part, a result of battery manufacturing, which requires the mining, transportation, and processing of raw materials, often extracted in unsustainable and polluting ways.6 Battery manufacturing also requires high energy intensity, which can lead to increased GHG emissions.7

In China, for example, the raw materials and manufacturing process of a single gasoline car produces 10.5 tonnes of carbon dioxide, while it takes 13 tonnes of CO2 to produce an electric vehicle.8 Equally, a recent Vancouver study of comparable electric and gas-powered cars found that the manufacture of an electric vehicle uses nearly twice as much energy as manufacturing a gas-powered vehicle.9

But the differences in manufacturing, including raw materials extraction, need to be placed in the context of the entire life cycle of the vehicles. The majority of a gas vehicle’s emissions come not in the manufacturing process but in the cumulative time the vehicle is on the road. By comparison, raw materials and manufacturing play a larger role in the total life-cycle emissions of electric vehicles.10

On average, roughly one-third of total emissions for EVs come from the production process, three times that of a gas vehicle.11 However, in countries like France, which rely on low-carbon energy sources for their electricity production, the manufacturing process can constitute 75% to nearly 100% of a vehicle’s life-cycle GHG emissions.12 Once the vehicle is produced, in many countries emissions drop precipitously.

So while EV manufacturing produces higher emissions than the production of a gas-powered car does, a lifetime of low- to zero-emissions driving leads EVs to have greater environmental benefits. While, as we saw, manufacturing emissions are higher in China for EVs than for gas-powered cars, over the lifetime of the vehicles, EV emissions in China are 18% lower than fossil-fueled cars.13 Likewise, the Vancouver study cited above found that over their lifetimes, electric vehicles emit roughly half the greenhouse gases of comparable gasoline cars.14 And the benefits of EV driving come quickly after manufacturing: according to one study, “an electric vehicle’s higher emissions during the manufacturing stage are paid off after only two years.”15

Driving

The longer an EV is on the road, the less its manufacturing impact makes a difference. Driving conditions and driving behavior, however, do play a role in vehicle emissions. Auxiliary energy consumption (that is, energy not used to propel the car forward or backward, such as heating and cooling) contributes roughly one-third of vehicle emissions in any type of vehicle.16 Heating in a gas-powered car is provided by waste engine heat, while cabin heat in an EV needs to be generated using energy from the battery, increasing its environmental impact.17

Driving behavior and patterns, though less quantifiable, also matter. For example, EVs are far more efficient than gas-powered vehicles in city traffic, where an internal combustion engine continues to burn fuel while idling, while in the same situation the electric motor truly is idle. This is why EPA mileage estimates are higher for EVs in city driving than on highways, while the reverse is true for gasoline cars. More research needs to be done beyond specific case studies on the different driving behavior and patterns between drivers of EVs compared to gas-powered vehicles.18

Traffic Pollution

While most studies of the benefits of electric vehicles are understandably related to greenhouse gas emissions, the wider environmental impacts of non-exhaust emissions due to traffic are also a consideration in the life-cycle analysis.

The negative health consequences of particulate matter (PM) from road traffic are well-documented.19 Road traffic generates PM from resuspension of road dust back into the air, and from the wear-and-tear of tires and brake pads, with resuspension representing some 60% of all non-exhaust emissions.20 Due to the weight of the battery, electric vehicles are on average 17% to 24% heavier than comparable gas-powered ones, leading to higher particulate matter emissions from re-suspension and tire wear.21

Braking comparisons, however, favor EVs. Fine particles from braking are the source of approximately 20% of traffic-related PM 2.5 pollution.22 Gas-powered vehicles rely on the friction from disc brakes for deceleration and stopping, while regenerative braking allows EV drivers to use the kinetic force of the motor to slow the vehicle down. By reducing the use of disc brakes, particularly in stop-and-go traffic, regenerative braking can reduce brake wear by 50% and 95% (depending on the study) compared to gas-powered vehicles.23 Overall, studies show that the comparatively greater non-exhaust emissions from EVs due to weight are roughly equal to the comparatively lower particulate emissions from regenerative braking.24

Fueling

Beyond manufacturing, differences in fuel and its consumption are “one of the main drivers for life-cycle environmental impacts of EVs.”25 Some of that impact is determined by the fuel efficiency of the vehicle itself. An electric vehicle on average converts 77% of the electricity stored in its battery toward moving the car forward, while a gas-powered car converts from 12% to 30% of the energy stored in gasoline; much of the rest is wasted as heat.26

The efficiency of a battery in storing and discharging energy is also a factor. Both gas-powered cars and EVs lose fuel efficiency as they age. For gasoline cars, this means they burn more gasoline and emit more pollutants the longer they are on the road. An EV loses fuel efficiency when its battery becomes less efficient in the charging and discharging of energy, and thus uses more electricity. While a battery’s charge-discharge efficiency is 98% when new, it can drop to 80% efficiency in five to ten years, depending on environmental and driving conditions.27

Overall, however, the fuel efficiency of a gas-powered engine decreases more quickly than the efficiency of an electric motor, so the gap in fuel efficiency between EVs and gas-powered cars increases over time. A Consumer Reports study found that an owner of a five- to seven-year-old EV saves two to three times more in fuel costs than the owner of a new EV saves compared to similar gas-powered vehicles.28

Cleaning the Electricity Grid

Yet the extent of the benefits of an electric vehicle depends on factors beyond the vehicle’s control: the energy source of the electricity that fuels it. Because EVs run on standard grid electricity, their emissions level depends on how clean the electricity is going into their batteries. As the electricity grid gets cleaner, the cleanliness gap between EVs and ICE vehicles will grow only wider.

In China, for example, due to a large reduction of greenhouse gas emissions in the electricity sector, electric vehicles were projected to improve from 18% fewer GHG emissions than gasoline cars in 2015 to 36% fewer in 2020.13 In the United States, annual greenhouse gas emissions from an electric vehicle can range from 8.5 kg in Vermont and 2570.9 kg in Indiana, depending on the sources of electricity on the grid.29 The cleaner the grid, the cleaner the car.

On grids supplied exclusively by coal, electric vehicles can produce more GHG than gas-powered vehicles.30 A 2017 comparison of EVs and ICE vehicles in Denmark found BEVs “were not found to be effective in reducing environmental impacts,” in part because the Danish electricity grid consumes a large share of coal.31 By contrast, in Belgium, where a large share of the electricity mix comes from nuclear energy, EVs have lower life-cycle emissions than gas or diesel cars.32 In Europe as a whole, while the average EV “produces 50% less life-cycle greenhouse gases over the first 150,000 kilometers of driving,” that number can vary from 28% to 72%, depending on local electricity production.15

There can also be a trade-off between addressing climate change and addressing local air pollution. In parts of Pennsylvania where the electricity is supplied by a high share of coal-fired plants, electric vehicles may increase local air pollution even while they lower greenhouse gas emissions.33 While electric vehicles provide the highest co-benefits for combating both air pollution and climate change across the United States, in specific regions plug-in hybrid vehicles provide greater benefits than both gas-powered and electric vehicles.34

How Clean Is Your Grid?

The U.S. Department of Energy’s Beyond Tailpipe Emissions Calculator allows users to calculate the greenhouse emissions of an electric or hybrid vehicle based on the energy mix of the electricity grid in their area.

Charging Behavior

If EV drivers currently have little control over the energy mix of their electricity grid, their charging behavior does influence the environmental impact of their vehicles, especially in places where the fuel mix of electricity generation changes throughout the course of the day.35

Portugal, for example, has a high share (55%) of renewable power during peak hours, but increases its reliance on coal (up to 84%) during off-peak hours, when most EV owners charge their vehicles, resulting in higher greenhouse gas emissions.”36 In countries with a higher reliance on solar energy, such as Germany, midday charging has the greatest environmental benefit, whereas charging during hours of peak electricity demand (usually in the early evening) draws energy from a grid that relies more heavily on fossil fuels.30

Modifying EV charging behavior means “we can use EVs to benefit the grid,” as David Reichmuth told Treehugger. “EVs can be part of a smarter grid,” where EV owners can work with utilities so that their vehicles are charged when demand on the grid is low and the sources of electricity are clean. With pilot programs already underway, he said, “we’ll soon see the flexibility inherent in EV charging being used to enable a cleaner grid.”

In the build-out of electric vehicle charging stations, the success of efforts to increase the environmental benefit of EVs will also rely on charging stations that use clean or low-carbon energy sources. High-speed DC charging can put demands on the electricity grid, especially during hours of peak electricity demand. This can require utilities to rely more heavily on natural gas “peaker” plants.

Reichmuth noted that many charging stations with DC Fast Charging are installing battery storage to cut their utility costs and also reduce reliance on high-carbon power plants. Charging their batteries with solar-generated electricity and discharging them during peak demand hours allows charging stations to support EV adoption at the same time that they promote solar energy even when the sun isn’t shining.37

End of Life

What happens to electric vehicles when they’ve reached their end of life? As with gas-powered vehicles, scrap yards can recycle or re-sell the metals, electronic waste, tires, and other elements of an electric vehicle. The main difference, of course, is the battery. In gas-powered vehicles, over 98% of the materials by mass in lead-acid batteries are successfully recycled.38 EV battery recycling is still in its infancy since most electric vehicles have only been on the road for fewer than five years. When those vehicles do reach their end of life, there could be some 200,00 metric tons of lithium-ion batteries that need to be disposed. A successful battery recycling program needs to be developed to avoid decreasing the relative benefits of EVs.39

It Only Gets Better

Periods in the life cycle of an electric vehicle can be more environmentally harmful than in similar periods of a gas-powered car, and in areas where the electricity supply is dominated by coal, EVs produce more air pollution and greenhouse gases than gas-powered cars. But those areas are far outweighed by the overall benefits of EV—and the benefits can only improve as EV manufacturing evolves and as electricity grids get cleaner.

Were half of the cars on the road electric, global carbon emissions could be reduced by as much as 1.5 gigatons—equivalent to the current admissions of Russia.40 By 2050, electrification of the transport sector can reduce carbon dioxide emissions by 93%, nitrogen oxide emissions by 96%, and sulfur oxide emissions by 99%, compared to 2020 levels, and lead to the prevention of 90,000 premature deaths.41

The electric vehicle industry is young, yet it is already producing cars that are environmentally more beneficial than their gas-powered equivalents. As the industry matures, those benefits can only increase.