[Peter Fox-Penner, Director, Institute for Sustainable Energy, and Professor of Practice, Questrom School of Business, Boston University; Jennifer Hatch, Research Fellow at the Institute for Sustainable Energy, Boston University; Will Gorman, ERG Graduate Student, and Researcher at Lawrence Berkeley National Laboratory]

A cleaner future with autonomous vehicles is not a sure thing. AP Photo/Jae C. Hong

The world is on the cusp of dramatic changes in the ways people own, operate and power their means of transportation.

Known as the “three revolutions,” a term coined by UC Davis transportation professor Daniel Sperling, the new trends are: electric vehicles, autonomous vehicles and sharing-oriented business models (think Uber and Lyft). Optimistically, these revolutions could make our cities a dreamscape of walkable urbanism that will reduce accidents to near zero and make more space for bikes, trees, pedestrians and small businesses while emitting no carbon emissions.

However, because these new technologies aim to dramatically reduce transportation costs, many people are concerned that more people will use autos to get around and the future will be filled with worse traffic and congestion. That could mean that consumption of fossil fuels will increase – bad outcomes for society’s sustainability goals.

We’ve analyzed a whole body of literature on autonomous vehicles and found that autonomous vehicles in particular will likely greatly increase overall transportation demand: With more options available, more people will take advantage of these autonomous vehicles and ride services. Whether there is a net increase or decrease in pollution from higher energy consumption, however, is less obvious.

The key factors affecting carbon emissions from these emerging transportation trends are whether vehicles are electric or use conventional internal combustion engine technology, and how quickly the electric grid can “decarbonize,” or generate power with no net carbon emissions.

Powering autos with the electric grid

Since 2016, transportation has been the single largest source of greenhouse gas emissions in the United States. As our electricity mix becomes less carbon-intensive and transportation demand grows, transportation will make up an increasing proportion of our carbon emissions if the U.S. continues to depend upon a system fueled by internal combustion engines and gasoline.

But how does our country realistically plan for a system that both meets the energy demands of our future transportation system and reduces our carbon emissions?

Our recent paper aimed to answer these questions. Our goal was first to incorporate the big but often overlooked trends in transportation to forecast how much transportation demand will grow. Second, we sought to create reasonable estimates for what is required to enable a clean, renewable and dependable electricity system in the years to come.

We reviewed both academic and industry research regarding future personal vehicle sales, energy efficiency improvements and total vehicle miles traveled as more people use autonomous vehicles.

These charts show the impact on emissions from a rapid shift to a less-polluting grid (left) or a more gradual transition based on government forecasts. In both cases, the key to lower emissions is whether light duty vehicles shift to electric and how clean the power grid is. Peter Fox-Penner, Will Gorman, Jennifer Hatch

This research allowed us to build a model that projects the number of electric and autonomous vehicles that could be on U.S. roads in the future and their related energy and emissions.

Our study estimates that by 2050 the net increase in electricity demand from converting the light duty vehicle fleet to electric, autonomous vehicles will be between 13 percent and 26 percent more than today’s total electricity demand. In the best case, where 95 percent of the electric sector decarbonizes by that time, this scenario would result in a reduction in greenhouse gas emissions of up to 80 percent from 2015 light duty vehicle greenhouse gas emissions.

Drilling down

A few interesting implications follow from of our greenhouse gas emission results. The first is that the rise in ride-hailing services and autonomy – assuming it is 100 percent electric – doesn’t drive significant increases in carbon emissions.

In our “stress case,” we assumed dramatic increases in vehicle miles traveled (VMT) due to autonomous vehicles, slow improvements in vehicle energy efficiency and limited transportation redesign. In this scenario, there was virtually no difference in greenhouse gas emissions compared to other cases with more conscientious policy planning, including VMT taxes, increased public transportation and other measures.

With more autonomous cars and ride-hailing services, more people are likely to use them, leading to potentially more combustion and pollution.  AP Photo/Jared Wickerham

This counterintuitive outcome might make a little more sense by diving into the results. In comparing different scenarios, we found that emissions are more than twice as high in a “low EV” scenario of 50 percent EVs in the fleet by 2050, compared to a “high EV” scenario of 86 percent EVs in the fleet by 2050.

This reflects how much more the shift in electric vehicles affects transportation pollution relative to other major trends in transportation. Even if there are more miles driven from autonomous vehicles, if they are electric and the grid becomes increasingly cleaner, then emissions won’t rise dramatically compared to the country’s current course.

Another takeaway that follows from this result is that society can only achieve dramatic cuts in greenhouse gas emissions by making the electric grid dramatically less polluting.

Optimistic scenario

Our study describes what is possible by 2050, and more or less what we believe we need to do in order to ensure the shift to autonomous vehicles and widespread ride-hailing services doesn’t lead to big spikes in pollution.

Of course, transitioning the grid to 95 percent to 100 percent clean energy won’t be easy; currently only 37 percent is from wind, solar, hydropower and nuclear. Nor will ensuring that almost all of our light duty vehicles are electric. That’s partly because EVs are not yet cost-competitive with internal combustion engine vehicles. Also, there are a number of infrastructure challenges to updating the grid for a major shift to electric transportation.

A massive conversion to electric vehicles and low-emissions power generation are needed to slow and lower rising pollution from transportation.  Portland General Electric, CC BY-ND

The good news for utilities is that the increase in electricity demand from electric vehicles will provide a positive, but not overwhelming amount of growth for electric utilities – growth that is welcome given the stagnant or declining revenues for electric utilities the last decade. This should come as a welcome opportunity and could create a strong ally as EV ownership grows.

Though our results represent time frames far out into the future, the policies that will lead us there are being written today. Our study suggests that in the near term, rapid and complete transport electrification and a carbon-free grid should remain the cornerstones of transport decarbonization policy. However, long-term policy should also aim to ensure AVs are electric and mitigate autonomous vehicles’ potential to increase driving mileage, urban and suburban sprawl, and traffic congestion.

And policymakers should not delay. The rise of Uber and Lyft have already dramatically upended business models that have existed for decades, and autonomous vehicle technology, which still has a few years to go before replacing human drivers, is already impacting cities around the country. The question now is whether these trends will reduce or increase our country’s emissions.

This article was originally posted on The Conversation.

[Gordon Bauer, ERG graduate student]

A Lyft ride-hailing car moves through traffic in Manhattan on July 30, 2018, in New York City.
Photo: Spencer Platt via Getty Images

Last week, New York City passed the nation’s first cap on new licenses for ride-hailing vehicles, like those driving for Uber and Lyft, citing in part concerns over worsening congestion and declining transit ridership. The decision represents the culmination of alarm over app-based ride-hailing companies and could serve as a blueprint for cities across the U.S.

Yes, but: Privately owned vehicles driven for personal use still dominate our transportation system, in large part because using one is cheap, fast and comfortable after the initial investment. Any regulatory solution to congestion must focus on personal vehicles first. Short of that, placing limits on Uber or Lyft will be a mere drop in the gas tank.

Despite rapid ride-hailing growth over the past few years, over 75% of all passenger miles in the U.S. are traveled in personal vehicles, and over 90% when air travel is excluded. By comparison, taxis and ride-hailing vehicles account for less than 0.5% combined, and all public transit less than 5%. Even in the New York City metropolitan area, personal vehicles account for over 75% of all land travel, versus 1.2% for taxis and ride-hailing vehicles.

Meanwhile, with the advent of self-driving cars, many of the reasons people currently take taxis or public transit — such as disability, aversion to driving, and difficulties with parking — might begin to disappear within the next few years. While some have predicted that autonomous vehicles will lead to the end of private ownership as we know it, this is hardly inevitable: No fleet operator will ever provide the same convenience of having a robot chauffeur in your driveway whenever you need it. And any cap on shared vehicles will make personal vehicles even more desirable.

Fixing transportation will require cities to foster alternatives to personal vehicles by incentivizing shared rides and integrating ride-hailing with public transit, and then implementing congestion pricing and eliminating parking in areas where people no longer need to drive. Otherwise, by the time personal automated vehicles develop a constituency, it will be too late.

The big picture: A new age of transportation is dawning, and we have a choice to make: Rethink the necessity of personal vehicles, or let their share of the transportation pie continue to grow larger and larger while public transit and ride-hailing fight over the diminishing crumbs.


This article was originally posted on Axios.

[Rachel Golden, ERG graduate student]

My alarm goes off at 4:30 on Saturday morning in a hotel room in Chowchilla, a small city (under 20,000) in the San Joaquin Valley, that feels like a deserted rural town. Unsure if I have slept at all, I slip quietly out of the hotel and slowly drive through a thick darkness. Silently freaking out and cursing Siri, I drive for 20 minutes in the wrong direction on the I-99. My counterparts later teased me that “you city folk don’t know how to drive in the Valley.”  It’s true, I’ve gotten lost twice in 24 hours.

Once I reorient and backtrack, I begin to see cars lined up like a silent train along the side of the road, about a mile from the Chowchilla fairground. The fairground parking lot is where Valley Clean Air Now (ValleyCAN) will be hosting the “Tune In and Tune Up” event in a few hours.  Hundreds of people spent Friday night in their cars alone, with loyal friends, or with their families to get a place near the front of the line. Several people even arrived at noon the day before in order to ensure entrance to the event. The lined-up cars are old. Really old. Most are “pre-OBDIIs,” (made before 1996) and are classified as some of the most polluting cars on California’s roadways.  It is said that cars are born in California’s coastal cities (like the Bay Area) and come to die in the Central Valley. Only, they don’t die. These cars clunk around for well beyond their expected lifespan on expensive life-support, because people have few options for transportation and depend on these wheels for groceries, work, and taking kids to school.

Jose in the early morning directing cars into the parking lot from where they were parked (and slept in) overnight

The people in line aren’t sleeping in their cars to get Taylor Swift tickets. Or a selfie with Barak Obama. They are there for a free smog screening and a $500 voucher to get the needed car repairs for passing the smog test—a prerequisite in California for keeping your car registered. Wait, this is a story about SMOG TESTS? No! Okay, yes. Well, sort of. It’s really a story about much more. This is a story about community groups coming together from all parts of life to make living a bit easier and healthier.

Some quick stats to set the context:

• Smog (i.e. ground level ozone), which is just one of the forms of air pollution caused by cars, can cause asthma, hurt the linings of lungs, aggravate chronic lung diseases such as emphysema and bronchitis, and reduce the immune system’s ability to fight off bacterial infections in the respiratory system.
• The San Joaquin Valley is home to the worst air quality in the country and has some of the highest rates of childhood asthma in California.
• Those most impacted by smog are children, adults who exercise or engage in outdoor physical labor (think agricultural and construction workers), and those with continued exposure (think everyone who lives in the Valley).
• Smog’s not all. These nearly 2-decade old cars also produce considerable hazardous air pollution, contributing to increased risk of cancer, heart and lung diseases, and diabetes.

I pull up to the fairground gates at 5:45am to see Tom Knox standing in the dark wearing his white ValleyCAN t-shirt and holding a bottomless cup of black coffee. Tom seems to be in a long-term relationship with caffeine, and this event, “Tune In and Tune Up,” is their baby. Tom is the executive director of ValleyCAN and has generously met with me weekly for my research. I spend the next hour discussing the day’s logistics with him and the event manager Jose Martin, a community organizer from outside of Guadalajara, Mexico. Jose tirelessly travels up and down the Valley, building support from community groups for these events, which occur every other weekend as far north as San Joaquin County and as far south as Kern County.

At 6:30am the sun starts to rise and Jose opens the gates to the fairground parking lot. We see the silent train come to life as over 500 cars turn on their engines one by one and roll into the lot, which is lined with orange cones and tents staffed by people in orange vests. Many of the cars are without license plates, about half are unregistered, yet most people are smiling because they are a few feet closer to getting that voucher to clean up their cars. 

Lideres Campesinas, the women who cook lunch for all participants and provide community education for farmworkers about sexual assault and abuse

To a bird in the sky, this event just looks like a parking lot. But on the ground, there is more than meets the eye. The traffic is directed and the event managed by local community groups, like gang prevention groups, who get a modest payment and work experience. The cars are screened by local, top smog testers and students from community colleges across the Valley. In school, the students only see one car a day, but out here they see up to 550 in a day. The students soon become experts, able to open up their own local smog test shops and return here as teachers. Women from the group Lideres Campesinas get paid to cook a free lunch for all participants and set up their table of educational flyers for agricultural workers about sexual assault and violence. Three radio stations set up their tents to blast music and broadcast live from the fairground parking lot to cover the event.

Veronica, who manages a pilot program funded by the San Joaquin Valley Air District that gives qualifying low-income Valley residents up to $5,000 to retire their old car and purchase and lease a new cleaner model

And in a small tent off to the side sits Veronica, who manages a pilot program funded by the San Joaquin Valley Air District that gives qualifying low-income Valley residents up to $5,000 to retire their old car and purchase and lease a new cleaner model. Paired with California’s Clean Vehicle Rebate Program, low-income drivers can get up to $12,000 to purchase or lease an advanced car like a plug-in hybrid electric vehicle (PHEVs). Since there are no PHEVs in dealerships in the Central Valley and inadequate chargers to keep these cars moving, most drivers opt for a smaller rebate for a less advanced vehicle, like a used minivan or occasionally maybe even an early-model Prius.

I can’t help wondering if some Berkeley environmentalists’ eyes are rolling. Cars are evil. Why aren’t they getting electric vehicles? What about public transit? We shouldn’t even be farming in the Valley anyway.

Yes, I know. Maybe I’m just sleep deprived, but the way I see it:  People live here, in the Valley. For their livelihood they need to drive long distances.

• Until we can make major system-wide changes so we can live in balance with the natural environment…
• Until state regulators (CPUC and CEC), utilities, and industry groups get EV charging stations installed at scale…
• Until the California Air Resources Board deploys hundreds of millions of dollars of cap-and-trade revenue to counties and community groups to increase low-income people’s access to EV cars, buses, and trucks…

Until any of this happens, simply retiring the oldest fleet and getting people into cleaner cars is the best game in town.

Until any of this happens, simply retiring the oldest fleet and getting people into cleaner cars is the best game in town.

Although it may make many environmentalists queasy, getting cars built in 1995 and earlier off the road for good, and replacing them with LEVIIs (cars made since 2008) will bring considerable air quality benefits to the Valley (i.e. reduced NOx, SOx, smog, particulate matter), improve fuel efficiency, and ease the financial burden for low-income people who are car dependent. This is just one first step in a longer-term game plan towards turning over the fleet and making way for near-zero emission vehicles.

In the meantime while the low carbon solution is being simmered and seasoned in state agencies and prodded by green groups, an under-the-radar smog event — which under most circumstances sounds like the last place to spend a Saturday afternoon — actually feels like a community party with music trumpeting, free food sizzling on the grill, and a team of unlikely partners bonding over a job well done.


Note: The views expressed here belong solely to the author of each entry and are not representative of the position of the Energy and Resources Group, UC Berkeley.