The best of EcoWatch, right in your inbox. Sign up for our email newsletter!
Mass-Market Electric Pickup Trucks and SUVs Are on the Way
By Venkat Viswanathan and Shashank Sripad
Electric vehicles — specifically, the Tesla Model 3 — are dominating the U.S. market for premium sedans, but are barely even on the radar in the busiest automotive category, which includes SUVs and pickup trucks.
The immediate reason is economics, but it has a lot to do with physics as well: Larger, heavier, less aerodynamic electric vehicles need larger, heavier, more expensive batteries to power them. Our research has looked at the energy needed to move cars and trucks along the road, and has identified the important factors that affect power usage.
We have developed an applet that can provide estimates of how much energy an electric vehicle would need to carry on board for a given driving range. This lets consumers determine how big a battery pack their car will need. The applet can provide a comparison of difference in energy consumption among sedans, pickup trucks and SUVs. Tesla's Model 3 and the Model Y crossover SUV will use the same battery pack, so our applet lets consumers compare the difference in driving range between a sedan and SUV.
How Do Electric Vehicles Work?
There are three forces resisting any effort to move a car on a flat road: wind resistance, friction from the road and inertia. Using the specifications of a vehicle's design, including its weight, dimensions and shape, we can calculate the energy needed to get the vehicle to start and stay moving. From there, we can determine how long the car can travel at a certain speed, and estimate how far it can go before needing to recharge its batteries.
The actual range of the vehicle can vary widely, depending on the exact driving scenario, such as moving on a highway or driving in a city. The U.S. Environmental Protection Agency (EPA) provides a set of standardized drive profiles for different conditions (such as urban, highway or a combination), each of which specifies the speed of the car as it travels. The EPA also publishes a certification report that provides many characteristics, including the battery pack size and range of a given vehicle. This provides a consistent set of data with which we compare different cars, SUVs and trucks.
Rivian R1S Electric SUV - Exterior and Interior Walkaround - Debut 2018 LA Auto Show youtu.be
Those sorts of calculations are common for gas-powered vehicles. Electric cars also have an additional element to factor in: regenerative braking, which lets cars recharge their batteries when slowing down.
An early test of our approach involved the Tesla Model 3. We calculated how much energy it would need, how much it could regenerate along a trip and how much battery storage would need to be on board. We predicted that for the car to fulfill its promised 310-mile range before needing to recharge, it would have to store about 80 kilowatt-hours in its battery bank. That calculation was later borne out by the EPA certification report.
Since that first success, we have analyzed a wide range of electric vehicles, allowing us — and consumers — to compare their energy efficiency and power consumption, and earning us the title "Battery Police."
On to Electric Pickup Trucks
Trucks are bigger and, often, less aerodynamically designed than cars, meaning they typically encounter more wind resistance. Friction and inertia increase for heavier vehicles. All of those mean a truck needs more energy to get, and stay, moving.
Once we know the amount of energy, we can calculate the battery pack size or driving range. The price of battery packs has dropped significantly over the past decade.
By studying vehicle characteristics, we can help compare different electric vehicles' battery needs and costs, which can help consumers evaluate options when they're considering buying an electric car, a future SUV or an electric pickup truck. Within the applet, different vehicles currently can be selected. The change in driving range for different average driving speeds can be computed.
In addition, a custom electric vehicle with any battery pack size can be designed and the applet will answer questions about energy consumption, range and the total weight of the vehicle with the battery pack. This can be used to compare and understand the differences among vehicles.
Venkat Viswanathan is an assistant professor of mechanical engineering at Carnegie Mellon University.
Shashank Sripad is a Ph.D. candidate in mechanical engineering at Carnegie Mellon University.
Disclosure statement: Venkat Viswanathan is a consultant for Pratt & Whitney. He is a technical consultant, owns stock options and is a member of Advisory Board at Zunum Aero. He is a technical consultant for Quantumscape. His research group receives funding from Airbus A^3, Quantumscape, Zunum Aero, Volkswagen, Toyota Research Institute.
Shashank Sripad receives funding from Zunum Aero and Airbus A^3 to undertake research as a Ph.D. Student at Carnegie Mellon University.
Reposted with permission from our media associate The Conversation.
EcoWatch Daily Newsletter
A middle-aged married couple in China was diagnosed with pneumonic plague, a highly infectious disease similar to bubonic plague, which ravaged Europe in the middle ages, as CNN reported.
Dairy aisles have exploded with milk and milk alternative options over the past few years, and choosing the healthiest milk isn't just about the fat content.
Whether you're looking beyond cow's milk for health reasons or dietary preferences or simply want to experiment with different options, you may wonder which type of milk is healthiest for you.
At least 1,688 dams across the U.S. are in such a hazardous condition that, if they fail, could force life-threatening floods on nearby homes, businesses, infrastructure or entire communities, according to an in-depth analysis of public records conducted by the the Associated Press.
By Sabrina Kessler
Far-reaching allegations about how a climate-sinning American multinational could shamelessly lie to the public about its wrongdoing mobilized a small group of New York students on a cold November morning. They stood in front of New York's Supreme Court last week to follow the unprecedented lawsuit against ExxonMobil.
By Alex Robinson
Leah Garcés used to hate poultry farmers.
The animal rights activist, who opposes factory farming, had an adversarial relationship with chicken farmers until around five years ago, when she sat down to listen to one. She met a poultry farmer called Craig Watts in rural North Carolina and learned that the problems stemming from factory farming extended beyond animal cruelty.
Temperatures plunged rapidly across the U.S. this week and around 70 percent of the population is expected to experience temperatures around freezing Wednesday.