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Electric Vehicles Can Meet Drivers' Needs Enough To Replace 90 Percent of Vehicles Now On The Road (phys.org)

An anonymous reader writes from a report via Phys.Org: Researchers at MIT have just completed the most comprehensive study yet to address whether or not existing electric vehicles could bring about a meaningful reduction in the greenhouse-gas emissions that are causing global climate change. Yes, they can. The study was published today in the journal Nature Energy. Phys.Org reports: "'Roughly 90 percent of the personal vehicles on the road daily could be replaced by a low-cost electric vehicle available on the market today, even if the cars can only charge overnight,' Trancik says, 'which would more than meet near-term U.S. climate targets for personal vehicle travel.' Overall, when accounting for the emissions today from the power plants that provide the electricity, this would lead to an approximately 30 percent reduction in emissions from transportation. The team spent four years on the project, which included developing a way of integrating two huge datasets: one highly detailed set of second-by-second driving behavior based on GPS data, and another broader, more comprehensive set of national data based on travel surveys. Together, the two datasets encompass millions of trips made by drivers all around the country. By working out formulas to integrate the different sets of information and thereby track one-second-resolution drive cycles, the MIT researchers were able to demonstrate that the daily energy requirements of some 90 percent of personal cars on the road in the U.S. could be met by today's EVs, with their current ranges, at an overall cost to their owners -- including both purchase and operating costs -- that would be no greater than that of conventional internal-combustion vehicles."

24 of 990 comments (clear)

  1. Driving yes, but charging? by houstonbofh · · Score: 5, Insightful

    How about all the people that live in apartments with first come first serve parking? Or people that park in the street? Or way down the street? Overnight charging is not simple for everyone.

    1. Re:Driving yes, but charging? by TheMiddleRoad · · Score: 5, Interesting

      People don't have gas stations at home either. Building up infrastructure at home, work, and shopping centers can solve that issue. Every powered kiosk for street parking in urban areas can become a paid charging station. I know plenty of workplaces that offer charging during the day. As for people in dense urban areas like NYC, they largely don't have cars.

      We have two 240v charging stations in the garage, for our two super-cheap EVs (Chevy Spark EV and Fiat 500e). Our rooftop solar power production offsets approximately 100% of the power we use, including the cars and electric water heating. We have two other cars that rarely get used.

      Rock and roll.

    2. Re:Driving yes, but charging? by Anonymous Coward · · Score: 4, Insightful

      The difference is that people don't have to sit at a gas station overnight. Because filling up your car only takes 10 minutes at a gas station (max), not everyone needs to have one. When you can pull into an electric charging station and leave ten minutes later with a full charge, people will start using electric cars. Also, when it becomes as cheap to buy an electric car with equivalent range (thinking about $12K Honda Civics that get 40mpg).

    3. Re:Driving yes, but charging? by Izuzan · · Score: 4, Insightful

      but how far can you drive on a 10 minute charge. im pretty sure the person spending 10 minutes to fill a tank can go 2 or 3x's the distance you can on a full nights charge.

    4. Re:Driving yes, but charging? by Izuzan · · Score: 4, Insightful

      good deflection.
      It takes me about 3-4 minutes to fill my 65l tank in my charger. that allows me to go about 500km before a refill. that overnight charge of yours allows you to go how far ? from 100- to at best 170km at a go ?

    5. Re:Driving yes, but charging? by Dare+nMc · · Score: 3, Insightful

      > I spend less of my time charging my EV than you spend filling your car's gas tank.
      I am not sure about that, it takes me 3 minutes to fill my truck with 30 gallons about once a month, gets me about 600 miles between fills.
      90 seconds / 20 driving days equals about 4.5 seconds per day. I fill up at 5 am in the morning, it is truly stop swipe fill, done. It also lines up with the time and rate I need to clean bugs off my windshield.
      I would estimate it takes you double that time, 4 seconds to plug in, 4 to unplug, and also having to have a dedicated parking location, so that would likely more than make up for the 10 minute oil change every 6 months.
      Since significant time of the year, I park on the street, it would take me about as much time to run a cord out to the car and back every day as a full fill up.

    6. Re:Driving yes, but charging? by kheldan · · Score: 4, Insightful

      I arrive home, plug in and leave it.

      How nice for you. However you're totally ignoring the original commetors' point: Not everyone lives in a HOUSE, many people live in apartments or other places where it becomes very very problematic to have to plug in a vehicle to charge it overnight. No apartments I ever used to live in would tolerate people running extension cords out their back windows every day, and that's assuming you could even park that close. No way the vast majority of property owners would ante up for EV charging stations, and in a large apartment complex there would have to be dozens of them to serve everyone.

      The real problem boils down to infrastructure. We've had a hundred years to build up the infrastructure to refuel IC engine vehicles pretty much anywhere. EV charging stations are few and far between and even high-voltage high-current types like Tesla uses aren't as fast as dumping gasoline into your tank. It will take decades to build up the infrastructure to serve mass amounts of electric vehicles, and it still won't be anywhere near as fast as refilling a liquid fuel tank. It'll take decades more to progress battery technology to the point where it's as fast and convenient to recharge as it is right now to dump 10 or 12 gallons of fuel into a tank. That's assuming the idea ever catches on enough that a large enough fraction of the population moves to electric vehicles to force the changeover. Face it, we've got a long, long ways to go yet before electric vehicle acceptance is not only popular, but practical.

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    7. Re:Driving yes, but charging? by bferrell · · Score: 5, Insightful

      The entitled are desperate to keep people from thinking about not having a garage.

      Battery electrics basic assumption is that of entitlement... Everyone owns their dwelling and has access to a charger dedicate for their individual use. Just another way of saying "I got mine, so screw you"

      Silicon valley is already seeing "charger rage" incidents where access to shared chargers just isn't working.

    8. Re: Driving yes, but charging? by superdave80 · · Score: 5, Funny

      1. We can use my wife's car.

      Given that this is /., that isn't going to be an option for about 90% of the people here...

    9. Re:Driving yes, but charging? by tsotha · · Score: 5, Insightful

      People who don't have power where they park is a "fringe case"? That's daft.

    10. Re:Driving yes, but charging? by serviscope_minor · · Score: 4, Funny

      People are already using electric cars.

      No they're not. I can't hook my semi trailer up to any car electric or otherwise and then drive coast-to-coast without a break to refuel let alone pee. In fact come to think of it, I doubt anyone really uses cars anyway since you just can't haul cargo like you can with an 18 wheeler.

      --
      SJW n. One who posts facts.
    11. Re:Driving yes, but charging? by Anonymous Coward · · Score: 5, Insightful

      Electric cars _really don't_ have "just as much maintenance". Combustion engines are relatively high maintenance gear, they have a LOT of moving parts, which all wear out and need lubricant changes. An electric car drive train is much, much simpler, which means less to maintain. There are probably dozens of electric motors in your home, but you never think about "Man, when does the DVD player next need an oil change?" because they're low maintenance.

    12. Re:Driving yes, but charging? by FlyHelicopters · · Score: 3, Interesting

      People are already using electric cars.

      Not very many, the number is a rounding error...

      People also own their own airplanes and helicopters, yet that doesn't mean those are going to take off as everyone's means of travel either...

      EVs have a long way to go...

    13. Re:Driving yes, but charging? by smallfries · · Score: 4, Informative

      No - the headline is misstating the paper.

      According to the abstract at Nature it is 90% of "vehicle days". 90% of vehicles would be a much stronger result. Because it is vehicle-days you cannot assume how they are distributed across the owners of vehicles. There is a post much higher up that calls it right: "electric cars would fail their owners 10% of the time: 36.5 days a year".

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    14. Re:Driving yes, but charging? by jafiwam · · Score: 4, Interesting

      No, you're just trying to use a fringe case to favour your bias..

      People buy stuff FOR the fringe cases.

      The cooler that can keep stuff frozen for 48 hours is a fringe case.

      The video card that can do 60 FPS on the latest game is the fringe case.

      The stereo, laser printer, TV, and microwave are all tools used in small parameters but the fringe cases is what separates them from others of their kind.

      Ask any tradesman that does anything physical or with their hands about tools and they'll say "buy once cry once" essentially saying "buy for the fringe case"

      Insurance is fringe case all around.

      Travel and getting the car prepared for a 400 mile non-stop drive from "empty" in 15 minutes on the way out of town is a fringe case.

      You are completely delusional if you think the case of the average is what motivates people, and what makes a tool useful.

      So no, you are not right. You are just to narrow minded to think about the non-asbergers point of view when you think of all the little numbers in your head.

    15. Re:Driving yes, but charging? by Solandri · · Score: 4, Interesting

      And the cost of electricity is about 70 to 80% less than the equivalent cost of a gasoline car per mile.

      This is true right now because electricity use overnight is low, so the power companies charge lower rates. So if you're one of the few people with an EV, charging it overnight means you're paying discounted electricity prices. That's going to change if everyone gets an EV.

      Current U.S. household electricity use is about 900 kWh per month. A Nissan Leaf is rated at 30 kWh/100 miles. Average vehicle miles traveled per household has been inching towards 60 miles (it dipped to 54 in 2009 - page 10). So driving those miles in EVs like the Leaf would result in about 550 kWh/mo of additional electricity consumption. Factor in charging efficiency (about 75%-80% from the numbers I've seen from Tesla and plug-in Prius owners), and it works out to closer to 700 kWh/mo. So adding an EV to the house will nearly double it's electricity use, with all of that additional consumption falling in the overnight period.

      Currently, power consumption ramps up around 8 AM and peaks around 8 PM. An EV in every garage would invert that so the peak would occur overnight between 8 PM and 8 AM (certain industrial use which runs 24/7 keeps current overnight use around 67% that of day use). Consequently, electricity prices would go from being lowest overnight, to highest overnight. (This is also why the idea of using the battery in your EV to store up cheap overnight power for use during the day is never going to go anywhere.)

      An EV is still cheaper to operate per mile than an ICE vehicle (because per Joule, gasoline is about 10x more expensive than coal). But instead of 70%-80% less cost per mile than an ICE, you're probably going to be in the neighborhood of 50%-60% less.

  2. Re:90% of trips != 90% of drivers by Kobun · · Score: 5, Interesting

    I routinely rent cars for the weekend for less than $30 per day. For that once-every-4-months trip where an electric wouldn't cut it, this seems like a viable solution.

  3. Probably a flawed analysis by Solandri · · Score: 4, Interesting
    I don't subscribe to Nature so I can't read the article, but from the abstract:

    We find that the energy requirements of 87% of vehicle-days could be met by an existing, affordable electric vehicle.

    It sounds like they analyzed in terms of vehicle-days, not in terms of owned vehicles. The press "helpfully" converted this into "90% of vehicles" which is inaccurate. Yes, probably 90% of vehicles driven on any given day could be replaced by current EV ranges. But I'd guess probably 95% of vehicles can't be replaced by current EV ranges. See, the vast majority of cars are driven short distances nearly all days. But a few times a year they're called on to drive 200-500 miles in a day, for things like that drive to Grandma's for Thanksgiving, weekend trip to Vegas, etc.

    If you applied the same type of analysis to car safety, you'd find that 99.99% of vehicle-days, seat belts don't protect you. And therefore it'd be ok to get rid of seat belts in cars.

    The flip side of this is that vehicle-days is a valid metric if you can convince people to rent an ICE car for their few trips a year which exceed an EV's range. People erroneously think they've paid a lump sum for the car when they bought it, so driving it for that one long trip is "free" while they have to pay "extra" money if they rent a car. I've been trying for years to convince people that the cost of a car (as well as most other things) is a rate, not an amount. The cost of fuel, maintenance, and depreciation to operate a car is usually in the ballpark of 40-50 cents/mile (insurance drops out since it's mostly based on time).

    So driving 500 miles (round trip) to Grandma's for Thanksgiving actually costs you about $200-$250 of expenses and depreciation. Renting an ICE car for those few long trips is very competitive. And you can use your EV as for the other 95% of days.

  4. Re:Low cost? by 93+Escort+Wagon · · Score: 3, Insightful

    Your 98 Ford Escort gets about 20mpg. If you switched to a modern Ford Focus 2016, it would get 30+ mpg.

    I don't know about his 98 Escort, but my 93 Escort gets 35-36 mph on the highway and (the much more common scenario) 30 mpg when I'm just driving it a few miles a day from my house to the train station. And over the past decade I've averaged about one big (~ $1000) maintenance bill every couple years.

    If you want to use safety as a selling point, you'll have a better argument - but not gas mileage and not overall cost.

    --
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  5. 90% of time not 90% of vehicles by Roger+W+Moore · · Score: 5, Insightful

    The oil industry and fossil car industries are desperate that people not realise how convenient it is to have a charger in your garage.

    For everyday around town use the home charger is fine. The problem is that it is not really 90% of vehicles that the electric car could replace but a single vehicle 90% of the time (which is still 90% of vehicles on the road at any one time). ~10% of the time we used our car for going on holiday or taking long road trips for other reasons. This, along with the incredibly high price, is what makes an electric car impractical for me. The high price will probably get fixed with time but to go on holiday with the family I need a car with a large range that can be refuelled quickly. While I would love to have an electric car with that capability for around the same price as a petrol driven one that is not something I see happening any time soon.

  6. No they can't, I'm special by Loki_1929 · · Score: 4, Funny

    Electric cars won't ever work because I drive 3,000 miles each way to work every day across all the peaks of the Himalayas hauling seven shipping containers filled with concrete. And if an electric car can't do that without me having to stop along the way, it's a useless piece of shit that nobody can ever use for anything. /UsualElectricCarNaysayers

    --
    -- "Government is the great fiction through which everybody endeavors to live at the expense of everybody else."
  7. the best way to lie to the public is to use % by jellomizer · · Score: 4, Insightful

    Let's put it an other way so that 90% doesn't look so good.
    They are about 365 days a year. There is 10% time an electric car won't work for you.
    So that is being 36.5 days a year (over a full month) of times your electric car will fail you.
    And most people will not have the luxury to buy a second car for those extra times.

    In short that 90% number is saying that electric car technology and infrastructure isn't quite there yet. But packages in a way to fool people who do not want to dig into numbers.

    They still need to work on longer range faster full charging. I would love to see the day where I can choose an electric car... However the technology and infrastructure isn't there yet.

    --
    If something is so important that you feel the need to post it on the internet... It probably isn't that important.
  8. Re:Supply and storage by reboot246 · · Score: 3, Insightful

    "The power grid is very lightly used at night."

    That won't be true once you're charging millions of vehicles overnight. Plus, millions of homes are heated by electricity in the winter. On a cold January night the grid could very easily be overloaded.

    Same thing is true during the day in summer. Air conditioning plus millions of vehicles charging at work could stress the grid.

  9. Re: That's nice. by legRoom · · Score: 3

    Tesla M 3 start at the average price of a sold car in America

    No. The average price of a car sold in America is about $22,000, whereas the Tesla Model 3 starts at $35,000.

    The average new car purchase costs $33,560. However, 69% of cars sold are used with an average price of $16,800, because most people can't really afford to buy new. Furthermore, those numbers are probably the arithmetic mean, whereas the geometric mean (surely a lower number) would probably be more useful.

    Anecdotally, the geometric mean price of a car purchase among my own social circles (which encompass everything from the intermittently homeless up to the beginning of the upper class) is definitely MUCH less than $35,000, with a strong majority of the vehicles purchased being used. Anyone who thinks a $35,000 car is affordable to the average American adult is out-of-touch with the true economic condition of the general population.

    Some used 2017 Teslas might reach affordability for regular people in five years or so - or they might not; nobody knows for sure what the maintenance requirements and depreciation rate for the Model 3 will be like, yet.