Ask the Expert What’s Up with Electric Vehicles? Stories You May Like At Cornell, Sustainability Isn’t Just a Goal—It’s a Way of Life With Cornell’s ‘Solar Noon’ Clock, Bill Nye ’77 Aims to Leave a Legacy Fresh from Sustainability Success in NYC, Alum Leads Cornell’s ‘2030 Project’ on Climate Change An engineering professor weighs in on the challenges of ending our cars’ dependence on gasoline—and how they may be overcome By Beth Saulnier From the Tesla to the Chevy Bolt, all-electric vehicles are growing in popularity. But what are their advantages and drawbacks—and how close are we to kicking the gasoline habit for good? For insights, Cornellians tapped Khurram Afridi, an associate professor of electrical and computer engineering, whose areas of expertise include electronic power systems. First off, is it true that electric cars have been around for more than a century? Definitely. Until the early 1900s, there were roughly equal numbers of electric vehicles sold as there were internal combustion engine vehicles. But range was always an issue—and internal combustion engine technology became so much better and less expensive, electric vehicles essentially disappeared from the scene by the mid-1930s. Can’t some electric cars today go hundreds of miles between charges? That’s under optimum conditions; it’s not when it’s cold outside, or you have the radio and heat turned on. Anecdotally, your vehicle range may be half of what the manufacturer claims, when you take into account other factors—especially weather. What are some of the challenges of today’s battery technology? The first is that it’s expensive—somewhere between 30–40% of the cost of the vehicle. And its energy density—how much energy you can store, for a given amount of volume or weight—is about 1/100th that of gasoline. So a large part of the vehicle, both in terms of weight and space, is occupied by batteries—and you still don’t get the same range that you get with gasoline. What about charging time? That is another big issue. It takes less than five minutes to fill a car with gas, but for electric vehicles, it is very challenging. To give you a sense of what that involves: an incandescent light bulb uses around 60 watts, and home appliances such as an air conditioner or washing machine might use about 1,000 watts. But if you want to charge a car in five minutes, you would need a megawatt of power—a million watts. It takes less than five minutes to fill a car with gas, but for electric vehicles, it is very challenging. Even if cars can be charged at home overnight over the course of hours, what about road trips? You have to have infrastructure available across the nation, so you could comfortably say, “I’ll drive and stop to charge along the way.” But unless you have very high-power chargers, you’re going to have to spend some time charging. And even then, there could be a line, so you’d have to wait, or the charger could be out of service. But I don’t want this battery problem to seem like it’s a roadblock that can never be solved; there are lots of people working on better technology. Like what? Batteries come in different chemistries—some optimized to store more energy, and others to be more power dense, so you can charge and discharge them more quickly. Typically, electric vehicles compromise and use one chemistry which is not best for either. But some companies are developing technologies to hybridize the battery, using two chemistries and combining them through electronics. And there is another, more radical thing that people are looking at: removing the battery to a large extent, and replacing it with “charge on the go.” What’s that? You basically electrify the road and charge the vehicle from the roadway itself; there are companies in the U.S. doing pilots on it, and we are studying it in my lab. In this case, you’d have maybe a tenth of the typical battery size, something that gives you 30 miles of range instead of 300. Stories You May Like At Cornell, Sustainability Isn’t Just a Goal—It’s a Way of Life With Cornell’s ‘Solar Noon’ Clock, Bill Nye ’77 Aims to Leave a Legacy And on all the major interstates and state routes, one lane would deliver energy wirelessly; you’d just need enough battery power for your local commute. This could also address some of the environmental issues of batteries, like the need to mine lithium. Afridi in his lab holding an inductor, which stores energy in a magnetic field when electric current flows through it. Could this also solve the problem that most apartment dwellers can’t plug in cars at home? Yes, one of the reasons people are pushing for this continuous charging is that it could provide that equity. And it doesn’t have to happen while you’re driving; if you’re parked on the street, and there is wireless charging capability underneath, that would potentially serve you. In the meantime, what about plug-in hybrids—which can use either electricity or gas—as an option? Due to supply chain issues, they can be hard to find right now, and prices are much higher than usual; it is much easier to buy a vehicle with an internal combustion engine. And a hybrid does not achieve the long-term goal of net-zero emissions. But it gives you better mileage, so from that perspective it’s a good compromise. Let’s talk about performance. Are there concerns that electric cars don’t have enough pick-up to, say, pass on a steep hill? Tesla disproved the idea that electric cars were basically golf carts. In fact, today’s electric vehicles are much higher performing than combustion engines in terms of acceleration. Tesla disproved the idea that electric cars were basically golf carts. Do they also require less maintenance? Absolutely. There are far fewer moving parts—essentially just the electric motor—so less to wear out, as opposed to an internal combustion engine where you’ve got pistons, belts, and a cam shaft. Actually, one reason there is no great desire on the part of dealers to sell more electric vehicles is that a lot of their revenue comes from the service side. Given all the issues we’ve discussed: if you were a betting man, when would you wager that electric vehicles will be ubiquitous on U.S. roads? In 2021, there were 535,000 all-electric vehicles sold in the U.S. In 2022, the number was 800,000, comprising 6% of all new vehicle sales. And the Biden Administration has set a target that as of 2030, 50% of all sales will be electric. There are obviously going to be political pressures around that, including issues like restrictions on federal tax credits. But in terms of substantial numbers of vehicles on the road being electric, I would say: probably within the next 15–20 years. Top: Illustration by Caitlin Cook / Cornell University. Photos by Noël Heaney / Cornell University. Published April 20, 2023 Comments Bill Gilmore, Class of 1970 6 May, 2023 A question to you: All that is very interesting, and very relevant to the climate problem. It seems like a major concern is that the timeline for getting significant enough progress of adoption of electric vehicles is not good enough to meet the demands of getting to net-zero as fast as needed. What do you suggest in order to meet the demand for transportation on the timeline needed? Reply Clifford O Eddy, Class of 1952 7 May, 2023 A trace gas, carbon dioxide at about 0.044%, is shown to have negligible effect in diminishing earth’s nightime radiative cooling. See NASA Earth Observatory, desert Biome. There where carbon dioxide levels are normal, but water vapor is at low level [e.g. 0.01%], night is about 75F colder than the day, Where water vapor is 1% or greater the night is only 10-15F cooler than the day. QED Reply Richard Amacher, Class of 1970 8 May, 2023 I have had a Tesla Model 3 for about four years driving from SW Florida to northern Michigan. It is literally the best sedan I have owned, not that it couldn’t be improved. Tesla is a little different in that the Supercharger network is well built out. I can leave home without planning and drive to any corner of the U.S., even with the base model. I love the navigation, charging at home and little maintenance. It’s a choice, but most reservations can be erased in the first drive. Reply Robert Dona, Class of 1966 8 May, 2023 I’ve been driving a Chrysler Pacifica for four years, mostly in the Kansas City area, averaging 8,000 miles a year. I consistently average 85% battery/15% gas mileage with overnight home recharging and a very good network of local charging stations. I won’t go back to an ICE and am not ready for the range and charging limitations of an EV, especially in cold weather. I hope we will not face the political consequences of telling the public what they have to drive. Reply John Priest, Class of 1974 9 May, 2023 The ultimate goal is to reduce our carbon footprint. That being said, how is all of this electricity being produced? We’re still burning fossil fuels, mostly in the form of coal, to produce electricity. Where’s the gain in carbon reduction if the EV community demands more from the power grid? Reply Ben Rockey-Harris, Class of 2004 21 May, 2023 Coal is on its way out, its declining very rapidly. US generation in terms of GWh from coal has dropped by over 50% in the last 20 years, and its going to be gone soon: https://www.pbs.org/newshour/science/electricity-generated-from-renewables-surpassed-coal-in-the-u-s-last-year Reply Leave a Comment Cancel replyOnce your comment is approved, your email address will not be published. Required fields are marked *Comment * Name * Class Year Email * Save my name, email, and class year in this browser for the next time I comment. Δ Other stories You may like Students Flying High: Sophomore Is a Rising Star in the Birding World Chime In In Praise of Exercise, the True ‘Fountain of Youth’ Chime In Why Being a Student Chimesmaster Put Me ‘At the Top of the World’