Lets talk about range again.

How much range does your car need? A gas car has a range of X and an electric car has a range of Y. But these are not apples to apples comparisons. They mean different things. Here is why…

Gas cars have a range of 300 – 500 miles on a tank. When you run low you go into a gas station and fill up. It takes 10 to 15 minutes.
If you drive 12000 miles a year then you will do this 24 – 40 times per year. Nobody tops up their gas car at home.
You’ve spent 240 to 600 minutes in gas stations with your gas car.

If you drive an electric car, you plug it in at home every day. If you drive 12000 miles a year, you average 33 miles per day. If your car has an electric range of 150 miles and you never exceed 150 in a day, you never charge anywhere other than at home.
Time spent waiting to charge: 0 minutes. Electric car is a huge win.

If you exceed 150 miles 20 times per year ( 20 days of 300 miles or 10 days of 450 miles ), you will need to stop to charge those 20 times. ( Thats 3000 or 4500 miles in just 10 or 20 days and your daily average drops to 26 or 22 miles on the other days )
If it takes you 2 hours to charge each time then you spend 2400 minutes. Currently available charging technology at standard domestic supply power levels takes about this much time at a 240V 70A charging station in a parking lot ( when they exist, few have been installed yet )
If you use that time to eat or shop or do something else you wanted to do, its not wasted time. If you can spend that time doing something you wanted/needed to do anyway 75% of the time then we’re at 600 minutes of “wasted” time – the same ballpark as a gas car. That all depends on where charging is available – is it where you want to spend time.

Proposed charging technology will use higher current and higher voltage to reduce this time to the 30 – 45 minute ballpark. Now you’re looking at 600-900 minutes per year. And you still have the advantage that its just an outlet at a parking stall, we can put them places where we want to spend a half hour. If you can spend the time productively 75% of the time, now we are at 150-225 minutes of “wasted” time per year.

The electric car with 150 mile range becomes a time saver over a gas car with 400 mile range. Your electric car needs a long enough range to cover about 93% of your driving days to be a big time saver over the course of a year.

If you are hellbent to drive 600 miles in a day with a bottle to pee in and only want to eat drive-through, the electric car technology that is available right now will slow you down. If you want to stop for 3 meals for about a half hour each time, it may not slow you down at all. In this one extreme case that many people will do no more than once every couple of years – you have to try to schedule your stops with charging to make the electric car as convenient as a gas car. The rest of the time it should be possible to make it more convenient. If you want to do this a lot, then you may not find the electric car convenient enough.
However if you drive that much you may drive many more miles than the average, and then the cost savings of electricity versus gas will really add up.


7 responses to “Lets talk about range again.

  1. Case study: drove Seattle to Tucson and back (with sight-seeing detours) last winter, family of five with luggage for a four week trip (cooler, stroller, snow gear, computer, clothes, etc.), ~450 miles per day.

    Right there, the analysis stops. AFAIK, there’s simply no marketed EV available today that can do that.

    We made regular 30- to 60-minute rest stops, generally every two to three hours, mostly ate hand-made lunches, never used a drive-through, never peed in a single bottle. And we were able to arrive at the end of each day in time to get the kids settled in before dinner and have a relaxed evening (wouldn’t have been possible if we’d had to include a couple of 2-hour charging sessions amongst our breaks…and where are all these 240v/70A outlets anyway? I didn’t see any at any of the rest stops we used)

    Not even counting the issue of cargo/passenger capacity, that’s just not a feasible trip with today’s EVs.

    (And why would we _stop_ for three meals, when we can eat one before we get on the road and another when we finish up for the day?)

    Shorter charging times require a lot of new stuff, including high-capacity outlets. That’s fine if you’re driving to a retail district and shopping, eating lunch, whatever and someone’s installed infrastructure to support the EV. But what if you’ve just driven a couple of hours to have lunch with friends at their house where their highest-capacity outlet available is a 20A 120v plug?

    Come on. No doubt technology to support a complete replacement by EV is going to arrive one day. But let’s not fool ourselves into thinking it’s here now. One of the things, beyond basic utility, that made the gas-powered car so successful is how convenient it became; early motoring was an exercise in challenges and detailed planning, only suitable for the enthusiastic and stout-hearted. EV today seems a lot the same.

    I don’t disagree that there are number of use scenarios that work fine today. Commuting is a great application and applies to a huge proportion of driving done, for example. But there are things today that a gas-powered vehicle can accomplish that an EV can’t. Acting like there aren’t just distracts from productive conversations about what EV _can_ do better.

    I’d love nothing more than to be proven wrong. But where’s the EV that has every bit the utility our Suburban does? AFAIK, it can’t be had at any price. And unlike many SUV owners, we _do_ in fact take advantage of that utility on a regular basis.

    Even if a replacement existed, I don’t know that it’d make economic sense to buy one. We can buy a lot of gas (even at $10/gallon, over 10 years-worth for our driving habits *) for what a new Suburban-comparable EV would likely cost (probably at least $50K, but of course until someone is selling one, who knows?). But until such a replacement exists, it’s not even on my radar.

    (* 6000 miles/year average, 16 mpg = 375 gal/year, $50K/$3750 = more than 13 years of gas)

  2. I don’t think he’s saying the charging infrastructure or the electric vehicles for long family road trips exist today, just observing that there’s no technological or economic barrier to getting there.

    The Roadster proves a long-range EV is possible, and that it can be affordable compared to comparable vehicles. As Tesla and other automakers put EVs into mass production, the costs will drop while passenger capacity increases.

    My wife and I drive a 2002 Toyota RAV4-EV, made by Toyota for the California market, based on 1996 technology. It carries five people and has a range of 100 miles. If it used today’s batteries, it would have a 200-mile range. The sticker price was around $42,000 for a very low production vehicle and they were sold out of two year’s production as soon as they made them publicly available.

    It’s not that far to go from the RAV4-EV to a Suburban-comparable vehicle given the advances made over the past 13 years.

    Building the charging infrastructure is even easier, and very cheap compared to what buying foreign oil costs us.

    Are you really so willing to send your children to war to defend our interests in foreign oil rather than yield an hour or two on your optimal road trip and demand that we be given a choice in what type of vehicles we drive?

    • “I don’t think he’s saying the charging infrastructure or the electric vehicles for long family road trips exist today, just observing that there’s no technological or economic barrier to getting there.”

      I suppose that’s for him to clarify. It’s not how I’m reading it, and it’s specifically the implication that we can all switch _today_ that I take issue with. I’ve made very clear all along that I do expect the technology and infrastructure to advance to a point where EV is a practical solution for everyone, and that it’s only the implication that it’s already done so that I disagree with.

      As far as the RAV4-EV goes, I don’t see any indication that it’s directly applicable in this discussion. I don’t believe that the $42K list price was indicative of the actual manufacturing costs, and being basically a Corolla with a slightly different-shaped cabin, it’s hardly comparable to an eight-passenger truck platform vehicle.

      “Are you really so willing to send your children to war to defend our interests in foreign oil rather than yield an hour or two on your optimal road trip and demand that we be given a choice in what type of vehicles we drive?”

      Frankly, I find the above sort of statement inflammatory and very red-herring-ish. Little of our military activity in the Middle East — especially of late — has been in the defense of oil interests (rather, most of it has been driven by ideology), and there’s no real evidence that’s the trade-off to actually be made. And the whole “for the children” ploy is a bit over-worn, IMHO.

      Anyway, if the well-being of my children is of concern (which it is), it’s much more important to do things like reduce the miles they travel on the highway than to worry about the source of energy for traveling those miles.

      Besides, if I add two hours per day to an eight- or nine-day trip (which is what my example was talking about), I’ve just added two full days to the travel time. The characterization of my example as yielding “an hour or two on your optimal road trip” is highly misleading and prejudicial. It falsely belittles the importance of practicality in these discussions.

      • highspeedcharging

        My intent is to state that I believe there is neither a technological nor financial barrier to the charging infrastructure we need. I thought this was clear, I will make sure this is more clear in future posts.

        The only ideology I see that is in play with our military presence in the middle east is the ideology of using force to ensure our supply of oil. If there was no oil there most americans would never have heard of the middle east.

        I illustrated the time cost of the alternatives. If you can find overlap with your charging stops and stops you want to make anyway, the cost is greatly reduced. If you want to drive straight through with no stops, then you pay a penalty. I left it to the reader to interpolate between the two extremes on how much time penalty they would pay on their theoretical trip and be willing to pay. If you aren’t willing to give up the ability to drive all day without stopping, then don’t get an electric car.

      • “My intent is to state that I believe there is neither a technological nor financial barrier to the charging infrastructure we need. I thought this was clear, I will make sure this is more clear in future posts.”

        Thank you for the clarification. And no, while I can’t speak for anyone else, it wasn’t clear to me, especially in the context of replies directly specifically at my own comments.

        For what it’s worth…

        I don’t know what your intended audience for this blog is. If it’s supposed to be a cheer-leading blog for the existing EV community, then I don’t find any real fault in the construction. But if there’s a goal of evangelism here, IMHO there’s some room for improvement with respect to how opinions and facts (and definitely there’s some of each) are presented.

        If someone like me who, in spite of specific practical considerations that prevent wholesale bandwagon jumping-on, is basically already “on-board” with respect to the idea of EV and its great importance in our energy-dependent future, winds up feeling fed over-hype and even condescended toward, imagine what an actual skeptic might think.

        And if you just think I ought to STFU, that’s fine with me too. 🙂

  3. Pete,

    My response to your first post was definitely over the top. I apologize fo that. Now I better understand where you’re coming from.

    I understand how highspeedcharging’s most recent blog could be taken the wrong way if that’s the only post you’ve read, but if you read more of his work he paints a pretty clear picture of where we are now and where the technology can take us in the future.

    I totally agree that there are no road trip capable EVs currently on the market and that the current charging infrastructure requires planning and lots of patience for extended trips.

    The only production EV on the market now is the Tesla Roadster, an expensive, impractical two-seat sports car. While it totally covers daily driving for one or two people, it’s not a family road trip car by any means. It’s more of a proof-of-concept for EVs. Mr. highspeedcharging is at the cutting edge of executing on an extended road trip in an EV, and it’s not for the casual driver. (If you haven’t read his first post, I highly recommend it.)

    That said, lithium ion battery packs can be charged to 80% in 45 minutes given the right charging capabilities (which don’t yet exist for large battery packs). So, if Tesla (or someone else) delivers the promised (optional, at extra cost) 300-mile range Model S “7-passenger” sedan, you could easily drive 3 to 4 hours, stop for 45 minutes and be back up to 80% charge and good for another 3 to 4 hours of driving.

    That would seem to satisfy your road trip requirements, if/when that capability is delivered in a sufficiently large vehicle. This is probably the second hardest EV to deliver at a reasonable cost, the hardest being a pickup truck with significant towing capability. Those will definitely be the last pieces to fall into place.

    Personally, my thought is that the driving needs of most two-car households could be totally satisfied with one 100-mile range EV and one gas or hybrid vehicle for longer trips. It’s going to be a while before an EV will do everything that a Suburban can do, but that should not stop significant EV sales.

    Now we just need to get the automakers to start delivering the cars that we know are possible.

    • highspeedcharging

      This blog started to chronicle my 850 mile trip in an EV. When I tell people I bought an EV a lot of them think “what a waste of money, what do you do when you run out of extension cord?” I want to be able to respond with facts and analysis, so I google up stuff and try to figure it out so I have answers. I figured its better to save my notes here, its a nice public backup.
      I greatly appreciate the debate – without debate it’s hard to know your argument is valid.

      I went back and revised history on this post to make it a little more clear what I was thinking.

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