MIT study: Existing EVs can meet most drivers’ needs, and reduce carbon emissions

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Many electro-skeptics concede that electrification is the future, but maintain that major breakthroughs will be needed before EVs are practical. Others insist (despite the findings of studies, studies and more studies) that going electric has little impact on carbon emissions.

A new paper by MIT Professor Jessika Trancik and colleagues, published in the journal Nature Energy, gives the lie to both species of naysayers, finding that current EVs could meet the needs of about 90 percent of drivers, at a total cost no greater than that of legacy ICE vehicles. EVs could also play a significant role in meeting emissions reduction goals. Furthermore, assuming battery technology improves at the expected rate, by 2020 up to 98 percent of vehicles could be replaced.

“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 US climate targets for personal vehicle travel.” Overall, when accounting for emissions from today’s power plants, this would lead to a 30 percent reduction in emissions from transportation.

The MIT researchers integrated two huge datasets: a detailed set of second-by-second driving behavior based on GPS data, and another more comprehensive set of national data based on the 2009 National Household Travel Survey, which studied households across the country to learn how and where people actually do their driving. Together, the two datasets encompass millions of trips made by drivers all around the country.

Another interesting finding was that the potential for shifting to EVs is fairly uniform for different parts of the country. “The adoption potential of electric vehicles is remarkably similar across cities,” Trancik says, “from dense urban areas like New York, to sprawling cities like Houston. This goes against the view that electric vehicles – at least affordable ones, which have limited range – only work in dense urban centers.”

The study did identify one caveat: there will always be a small number of driving situations that require a greater range than that offered by lower-cost EVs. The writers suggest that such needs could be met by renting an ICE vehicle or using a car-sharing service (the study did not consider the possibilities of PHEVs).


Source: MIT News, MIT Technology Review

  • brian_gilbert

    No problems left if a country goes completely driverless with all vehicles hired. Only 10% of the vehicles needed which savesl all the pollution caused by the production of the rest. Effectively lowers cost of vehicle by up to 90% as vehicle used more intensively, suffers less wear and tear, and more reliably maintained. If charge runs out the hired vehicle simply stops at a charging point and tells you to change to a charged vehicle that is waiting there.

    • nordlyst

      I think you’re pulling numbers from thin air – or is it called making unqualified guesses?!?

      10% seems rather unlikely in my opinion. At least in the short to medium term. We are creatures of habit, and to make do with only 10% of the fleet you’d need not just autonomous cars that we can time-share, but actual ride-sharing where several people travel in the same vehicle, a bit like some airport taxi services function. I see no fundamental reason why we couldn’t learn to do this, but getting most people to that point likely takes decades. I’m certainly happy to bet it isn’t happening this side of 2030.

      • brian_gilbert

        No, I get my facts off websites such as the LandTransport Authority of Singapore which states that the vehicles in use at peak hours is less than 10% of the total. I have just personally travelled on the M1 in the UK with several slow traffic jams in the process. I have also lived in London for over half a century where congestion is the norm. A High Street nominally 2 lanes wide is often full of parked cars both sides with vehicles taking turns to use the remainder, one direction at a rime. 7 mph was the figure for rush hour traffic in London last time I saw it. So doubling the speed of vehicles with no parked cars does not seem difficult. The hired vehicles would usually carry the same people as a taxi soes now. The same number of taxis would carry double the number because of the increased speed. The incentive is the money saved. You have no car to pay for, maintain, insure etc, No drivers to pay for all those goods vehicles delivering at twice the speed.. Yourcommuting time halved. . A apreadsheet for Singapore taking the key figures into account shows a £5,000 return per person. IF Singapore adopts it and their standard of living goes up £5,000 per person per year, can you see the USA holding back?

        • nordlyst

          That is very surprising to me. Shocking, in fact – if accurate. Singapore is not a state where private car ownership is encouraged or very common. The city-state has gone very far towards a carpool model in the form of ubiquitous taxi services.

          Are you sure you haven’t confused peak use with average use – utilization? Could you provide a link?

          I believe utilization in most countries is only 5%. Singapore might be 10% since it has very few privately owned vehicles compared to other rich countries. But since most people like to sleep at home in their bed at night achieving a utilization much north of 66% seems unlikely ever to happen – unless we can teleport the cars and thus share them across time zones. 😀

          In any case it doesn’t really follow we can make do without the cars that are parked at peak hour. My car is in the garage waiting for me. If it were not, there would be some overhead for moving cars from where they are to where they are needed. While this should be a fairly small overhead in densely populated places like Singapore, it will be significant for at least half the population if we think globally.

          • brian_gilbert

            Nordlyst: Sorry I cannot quickly find my source for the 10% usage at peak hours in Singapore. HOwever to give a picture of how easy it is to find most figures just do a search for…
            singapore, land transport statistics in brief
            Up will come a 2 page mass of relavant stats.
            I expect 10% of the current number to be sufficient because on top of that being the max figure in use at present average speed will be much higher reducing the number needed even further. I expect there to be a trial with say a thousand vehicles to test my expectations and adjust them to reality but they seem reasonable now.
            Your car is in your garage eating its head off but many people have no close garge. ANother stat says 30% of journey time is spent searching for a parking space and then walking to ones destination. That garage of yours could be an extra room in your house worth maybe tens of thousands of pounds.
            I agree that vehicles will waste time reaching a pickup point when called but a central computer will minimise this time. Only trials will tell how much time is wasted this way.

          • nordlyst

            Boy am I glad to live in a small city in a small country!

            I seldom spend more than five seconds to find a parking space, and love being able to drive my EV on hydropower with a pretty good conscience. 😉

            Obviously this isn’t reality in most places.

            I know I can find numbers if I make a little effort, but I don’t actually think it matters that much. In terms of policy we should act the same whether the figure is 40% or 5%. And autonomy will be key. I fully agree that the current state of affairs where most cars are literally just in the way most of the time can be radically improved upon!

  • pj47tech

    I would question the assertion that by 2020 98% could be replaced. The northern climates alone and the subsequent range reduction due to extreme cold temperatures would reduce the number of EVs suitable for daily commutes.

    • nordlyst

      True. And yet EVs have at times held no less than 25% market share in Norway – and this year’s survey by the Norwegian EV association, of some 5000 owners, shows that only 1% say they don’t want to get an EV next time.

      It is important to understand though the majority of households with EVs in Norway have at least two cars with one being an ICEV – 73% if memory serves. Among the minority that only have electric cars, most have a Tesla.

      There are few like me who drive a LEAF and don’t have a fossil-fueled car in addition. But in the 16 months I’ve had my car I have needed another car only twice. Once I rented a small van at IKEA for three hours to haul furniture home. And once I borrowed a gasoline car to drive 700 km in a single day – a trip that would have been possible, but neither particularly cheap nor much fun in the LEAF since I’d have had to fast charge perhaps eight times all in all!

      I do agree though that 98% of the cars could not have been replaced without people making adjustments. There may well be more than 2% of cars that commute longer than the first-generation cars can go in winter time (or even in summer time, for that matter). And much more than 2% need towing ability, something only Model X offers today (and even with 90 kWh range is too limited to make towing camping wagons an attractive proposition).

      But in the real world, the question of what percentage of cars currently on the road do a job that an EV could do just as well is utterly irrelevant to how many can in practice be sold between now and 2020. Say 50% of cars on the road can be replaced by EVs. If every new car sold starting tomorrow was an EV, and sales remained the same, it would take 8-10 years to replace half the fleet..!

      • pj47tech

        Excellent thoughts. I’m not sure if the typical driving pattern in Norway is like the typical driving pattern in the US, in terms of commute miles/etc. Near some metro areas in the US commute times push one hour. Some people willingly live 2 hours away!

        I have 3 vehicles, and they are each unique and specialized for the function I wanted. One economy ICE (small Honda), one near road racing car, and one one tow vehicle (pickup) that also hauls my larger items for home repairs/etc.

        If I replaced my small Honda with an EV I’d only find it useful for maybe 60-70% of what the ICE car can do. We use it for longer trips when we don’t need larger hauling capacity. And certainly the EV could never do what the other two do.

        • nordlyst

          I don’t have any numbers on hand for average commute, but my guess would be that it is typically a little less over here than in the US.

          How far do you go on your trips? Are there charging opportunities along the routes you want to travel? (This is itself a problem IMO – the infrastructure needs to be near-enough omnipresent to make this question no more pertinent than it is for gas stations! You don’t really want to assume any particular routes when buying a car… you are supposed to buy travel freedom, no??)

          I bet if the ~24 kWh vehicles of right now could do the job 70% of the time, then the ~45 kWh vehicles and up of 2017, that are similarly priced, can do the job 95% of the time. That may not be enough, but at least the gap is rapidly closing.

          • pj47tech

            My trips are 150 to 1000 km (one way), sometimes longer, and most routes could have a charging station along the way. As long as the charging time is not more than two times longer than filling a gas tank, I’d be fine with that.

            Eventually we’ll get there. The transition time is the hardest for those of us with higher requirements.

          • nordlyst

            1000 km in a single day? I think that’s more than I have ever needed to do – 700 km is the longest I recall in one day. With a Model 3 offering 350 km of EPA range, but driving on highways, I reckon two charging stops of 15 minutes each would suffice. And I really ought to take those breaks regardless.

            Faster charging is welcome, but I don’t think it needs to be faster than 15 minutes. That is twice as fast as today, and the returns of further reduction are quickly diminishing.

            15 minutes is no more than a trip to the bathroom and getting a hot dog or a cup of coffee. I suppose if several people are travelling and take turns driving a shorter charging time could be attractive, but I think the value for most people would be really minimal.

            Don’t forget that 90% of the time you would spend only seconds plugging in at home or work. Perhaps not even that, as wireless charging is already possible and very efficient. So even if you went on long trips every week all year round, and had to spend 15 minutes charging, you would probably spend less time on filling up than you do now with an ICEV.

          • pj47tech

            The US is 5000 km across, so 1000 km is only 1/5 of the country’s width east to west. My personal longest trip in one day (under 24 hours ) was about 1800 km.

          • nordlyst

            Norway is merely 1752 km, although the coastline is perhaps 20 000 km (measured with a 1 meter yard stick). This has no bearing on how far I can responsibly drive in a single day.

            1800 km in a single day is 18 hours at 100 kph. Maybe you were going much faster, but even at 150 kph average speed it’s a massive 12 hours. I wouldn’t want to travel like that. 🙂

          • pj47tech

            Only averaged about 100 kph when moving. Took 21 hours, including breaks and stops (short naps to stay alert). I could do that in my younger days but not now 🙂 Don’t think I want to try that length in EV right now (or any other car!).

    • Frank Podesta

      pj47tech, I agree with you and of course the ultra smart individuals at MIT put in the word “could”, which is close to “might”, which you could add the word “not”. That sounds a lot easier to take than” could not”, for all of us.
      Finally some studies I have read stated that by 2040 ten percent of the World’s Electric power will be needed to charge all the electric vehicles. According to my calculations, along with the utility companies projections, that most of the vehicles will be charged at night time or from 5 oclock to 5 or 6 in the morning. Well no solar, then what? You bet Peaker Plants to meet demands at night that the utilities companys never had to worry about before. By the way , they either run on natural gas, or some other fossil fuel.
      The fact of the matter is that the ten percent needed to charge the EVs is only for a small percentage of EVs not 98%. God only knows how we would charge all of them.

      • Brandon Fouts

        Charge while at work with solar.
        Also don’t forget efficiency gains, LED lighting for example.
        Heat pumps (which is geothermal)
        Hot water on demand vs hot water tanks most of US use.
        Oil refineries use lots of electricity.
        You get the idea. Predictions are difficult, especially of the future.

        • Frank Podesta

          Brandon a lot of good ideas to save energy, however, when the demand from just the EVs hits us (the world), at a growth rate truly unexpected; how are we going to answer the question? Where is the supply of electricity going to come from. Solar in certain locations will not be the answer, and power plants use fossil fuels to produce energy for the most part. The costs of geothermal in certain areas is way too costly at this time and as Bill Gates stated earlier, the battery reserve technology is still too costly. He claims by using batteries for a reserve supply will cost around .30 cents a KWH. I agree predictions are difficult, but if you look at the past predictions claiming that by 2020 1% of the vehicles in California would be EVs, you can see that we had no idea at that time. That time was a year ago. What did we learn? The energy use for charging EVs will be far greater,.Most all the auto companies are coming around to EVs , and our need for charging EVs will be far greater, whatever the amount.
          By the way the Corporate businesses that you want to charge the cars in the day time do not have the power now and in most cases do not have the space to put in enough solar to solve the future problems.

  • nordlyst

    > can meet most drivers’ needs

    More accurate would be to say that the existing (affordable) EVs can meet most drivers’ needs most of the time. And therein lies the problem. 95% or even 98% isn’t good enough. It needs to be more than 99% or even 99.5% of the time.

    I have only a 2012 LEAF, but I live in a country where it would cost me much more to drive an ICEV. That means I can rent a car a few times a year and still save considerably by choosing to drive an EV. Had that not been the case I probably wouldn’t have got one in the first place.

    • mipak

      Borrow another family members car or a friends. If just one person in 20 had an ICE car as a backup for everyone else it would cover that 5% from the 95% and make it 100%. Make a deal on your city block for 2 or 3 ICE cars available for everyone on the block and the rest can have EV’s.

      Either that or buy a real clunker ICE car that can get the job done the few times a year it’s needed. Many weekend warriors already have that with a pickup truck used for 500 to 1000 miles a year (3 car family with the 3rd being a really cheap old pickup truck). You can get a clunker pickup truck for under $2500.

      • nordlyst

        You are assuming perfect allocation and zero overhead is possible, but point taken and I agree thad much could be done. It isn’t 5% though – unless you get half the people to take their summer leave in winter and the like. There is complicated logistics involved. But the biggest challenge is likely to be to get people to make small adaptations. It usually takes at least a decade to persuade any significant part of the population to make some minor change in their ways.

        I moved here a year ago, am in my forties and pretty on my own really. The family I have nearby drive have a Citröen C-Zero (i-Miev clone) and a Soul EV. I did borrow a VW Polo, the second car of my boss, once in order to drive 350 km for a business meeting and back again the same day, and I rented a small van from IKEA (operated by Hertz Carpool) for 3 hours to haul furniture.

        So yes, I can get by owning just a LEAF. But there are trips I would have taken if I had an ICEV that I have sacrificed. I could rent a car in a peer-to-peer car rental service (“nabobil” – neighbour’s car). It isn’t very expensive, but it does provide a disincentive for travel compared to just having your car stand by. Then again that isn’t such a dumb thing given our predicament!