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Electric car range

  1. Jan 31, 2010 #1
    The EV1 was produced in 1996 and could get up to 150 miles on a single charge,

    "The NiMH batteries, rated at 77 amp-hours (26.4 kWh) at 343 volts, gave the cars a range of 75 to 150 miles (120 to 240 km) per charge, more than twice what the original Gen I cars could muster."


    The Volt was produced in 2010 and could get up to 40 miles on a single charge,


    What's the deal with this? Why the huge step backward?
  2. jcsd
  3. Jan 31, 2010 #2


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    The EV1 is a pure electric car. The Volt is a hybrid. Hybrids are not meant to run exclusively on electric power at all times.
  4. Feb 1, 2010 #3


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    Also the Volt seats 5 while the EV1 seated 2.
  5. Feb 1, 2010 #4
    Both answers are correct.

    EV-1 had a big battery pack. Volt's pack is smaller (16 kwh) and it does not use the full range, which is supposed to help with battery longevity. When Volts finally roll out, I expect it would be a fairly simple matter to "hack" its software and raise the electric range from 40 to 60-70 miles.

    EV-1 was highly optimized and streamlined. It had the lowest coefficient of drag of all production cars ever (0.19), it was relatively small and light. The Volt is designed to be practical. We don't have all the final numbers, but we know that it's 10% taller than EV-1, and the coefficient of drag will be higher.
  6. Feb 1, 2010 #5
    Of course the funny unsaid point is that without chainging underlying energy infrastructure, an electric car is a switch from gasoline to (mostly) coal. *sigh*
  7. Feb 2, 2010 #6
    Last edited by a moderator: Apr 24, 2017
  8. Feb 2, 2010 #7
    And, since 1 kwh/kg = 3.6 MJ/kg is approximately the energy density of TNT, the military may be interested in that technology as well.
    Last edited by a moderator: Apr 24, 2017
  9. Feb 2, 2010 #8


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    Not mostly. The US electric system is less than half coal powered. In smog prone areas like California, there is very little coal power and there an EV replacement of the gasoline fleet would be huge emissions advantage. EV pollution benefits are at least substantial everywhere, and huge in urban areas. The sole exception is that EV's might bring on increased SOx emissions from running coal plants harder. Finally, given EV's we then at least have the option of improving/eliminating emissions by eventually replacing harmful emissions power plants.
    Last edited: Feb 2, 2010
  10. Feb 2, 2010 #9


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    The energy-density is high, but an inherent problem with http://en.wikipedia.org/wiki/Zinc_air" [Broken] battery technology brought on by the required diffusion of air into the battery is the specific power which is at least 3-4x less than current lithium ion batteries. Note that TNT for instance doesn't have any problem with power density.
    Last edited by a moderator: May 4, 2017
  11. Feb 2, 2010 #10


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    The combined range of the Volt is 4-500 miles, and it can refuel and be ready to go again in 5 minutes at the gas pump, versus the 12 or more hours required for the old EV1. And I doubt the 25kWh EV1 could do any more than 120 miles at highway speeds on its best day.

    Other advantages:
    o The 25kWh of NiMH batteries weighs 2-3X that of equivalent Li Ion, so that the (estimated) 750kg EV1 battery pack would weigh 250kg with today's Li Ion.
    o EV1 batteries would have lasted only 3-5 years (500 to 100 cycles). Volt battery should do 10 years.
    Last edited: Feb 2, 2010
  12. Feb 2, 2010 #11
    Agreed, but we have no rapid capacity to "fire up" wind-farms and doing that with hydroelectric power is purely regional. Nuclear generally runs at safe capacity, so your point that coal fired plants will definitely have to take on the load. I'm not going to be a happy bunny until we start going for genIII-IV nuclear reactors (pebble-beds and such) instead of coal, and/or commit to extracting Hydrogen using improved methods that don't require burning coal.

    However... we have a LOT of coal easy to hand, and a strong coal lobby. SOx, Mecury, etc... it could get ugly. Keep in mind that firing coal is a LOT dirtier than gasoline (yes, I'm ignoring the refinement process) in terms of particulate matter AND unwanted chemical emissions.

    You're right however... it gives us an option. EDIT: Oh, and how about new gen supercapacitors? Rapid charge rate, high load, no wear due to charge/discharge cycle. Yes, the materials and tech have a ways to go, but it would be a far better option than NiMH, Li-ion/air, Vanadium, etc.
  13. Feb 2, 2010 #12
    ....And they are interested. In fact, such batteries are being considered on some warships to store and use power from the onboard nuclear plant for use in weapon applications such as a rail-gun.
    Last edited by a moderator: May 4, 2017
  14. Feb 2, 2010 #13


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    Natural gas plants can (and do) fire up quickly.
    US also has ample natural gas.
    Pick your poison, but in general - no. Yes coal puts out more SOx, a little more particulate*, mercury, and radioactivity. Between the two, gasoline puts out more NOx, nearly all the CO, organics like benzene, gasoline vapor directly into the air, and noise, assuming the car is modern and tuned. Then that comparison is valid only if one is standing right next to both a tailpipe and a coal plant stack; generally populations lie around vehicles, not coal power plants. If EVs replaces ICE, then in the areas where the vast majority of the people actually reside it is no contest across the board: gasoline is much worse. Again this assumes EVs are sourced on all coal power, and they won't be.
    Only as a mix w/ chemical batteries: Double layer caps have high temperature degradation problems, low energy density.

    *Edit: unless we're talking about diesel.
    Last edited: Feb 2, 2010
  15. Feb 2, 2010 #14


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    And for catapults. Not metal air though.
  16. Feb 2, 2010 #15
    The impact of cars vs. industry in terms of carbon emission is negligable. The rest of the emisssion from cars do exist, but in trace quantities compared to SOx in particular. There are also the 75% elevated cancer rates in areas with coal fired plants, something that has never been matched by saaaay, people living near freeways.

    As for LNG/NG... the process of GETTING it, refining it (and use of byproducts), and finally transporting it have a fairly hefty environmental impact. We need to overhaul our power grid, build a LOT of nuclear plants, and then work our way to fusion (for the grid) and hydrogen fuel cells (for vehicles). It would probably take at least 50 years to follow that course, and yes, a complete switch to electric power in some areas would be great. Unfortunately, if everyone wanted an electric car today, and could get one, our power supply couldn't meet the demand (but as you pointed out that can change rapidly), but more importantly our power grid would fry.

    Ironic... an overhaul of the power grid, massive building of NG and Nuclear fired plants, and a renewed, but measured approach to developing sustainable Dueterium/Tritium fusion and a Hydrogen economy over the next half-full century... would be an enormous expense, but it would be the TRUE "New Deal" of this century. It'll never happen.
  17. Feb 2, 2010 #16


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    Then you're not looking, as that is mostly nonsense. The non CO2 emissions from gasoline, including SOx, are not 'trace' in comparison to coal. Both coal and petroleum combustion cause tens of thousands of actuarial deaths per year. Googling:

    Still better than coal. Much better.

    Almost everyone - http://www.sciencedaily.com/releases/2006/12/061211221149.htm" on today's grid.
    Last edited by a moderator: Apr 24, 2017
  18. Feb 2, 2010 #17
    Let be really clear... the traces I was speaking of was NOT CO2. I'm also not arguing FOR petroleum.

    Second, your 84% figure is based on one article, and one study, AND that assumes those vehicles are hybrids with 33 mile range batteries ALL being recharged at night. In a 220 million vehicle economy that is an absurd notion.

    By the way, of that 84% how much would be NG/Coal, and how would that compare to Petroleum (which is still going to be used in vast quantities in military and industrial proceses)? You're looking at this in a hyper-idealized fashion, and while there might be the idle generation capacity, there is no WAY that current plants coud run at full tilt 24/7.

    If 84% plug in at night, do you have any idea what that would do? There is little to no storage capacity in the grid so idling capacity is UNUSED, not purely wasted... although to keep any given plant fired does take some waste on off hours.

    The number of obvious holes in that study makes it about as useful as a model of a bullet that ignores gravity and friction.
  19. Feb 2, 2010 #18


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    Neither was I.

    I understand. You have been continuing to argue from the beginning that EVs are about the same as gasoline powered vehicles regarding harmful pollution - that switching to EVs wouldn't make much difference. That's wrong.

    Versus your assertion, that the grid would 'fry', which is based on no sources at all.

    Here's the original PNNL report;
    it has the percentage of grid information though it is mainly about emissions. If you are interested, comment directly on it. There's similar findings from the EPRI which google will reveal.
  20. Feb 2, 2010 #19
    You're being very selective in your counterpoints, focusing on nitpicky issues and then wanting me to google ****.

    Answer this honestly: What do you know about the age of current coal, NG, and Nuclear power plants, their retrofits, and how truly dated our energy infrastructure is? Do you understand the difference between potential to generate power, and the ability to transmit and transform (locally) that power? If you want to get into a dry and technical discussion about this, I'd really love to see some indication beyond a google search that you're familiar with these issues.
  21. Feb 2, 2010 #20


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    A great deal. The startup date and seasonal operating capacity of every power plant in the US is all public information.

    I understand the fundamentals of this issue quite well. You seem to be under the impression that through EVs on the grid will increase the peak load. No, if they're charged at night, that need not happen. The US system has more than 100GW(e) of slop in it from when it is running peak load in the day and at night. Running the same loads through the lines at night that they experience during the day will not degrade them noticeably. Finding downtime for maintenance is somewhat of an issue, but many gas peaking plants for instance are only running 20-30% capacity to accommodate.
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