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Wednesday, May 24, 2006

Plug-In Hybrids Are on the Way

Cars with advanced batteries get 100 mpg and boast far greater range than all-electric vehicles.

By Kevin Bullis
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A new nickel-metal hydride battery design cuts battery size and cost. Using it, this retrofitted Prius gets over 100 mpg. (The battery pack is located under the green controller box.) (Photo by Kevin Bullis with a Treo 650 camera phone.)

Last week in Washington, DC -- even as top executives from Ford, Chrysler, and GM asked lawmakers to subsidize the installation of more ethanol pumps at filling stations -- makers of new battery systems were letting U.S. senators test-drive prototype cars that get over 100 miles per gallon, but don't require any new infrastructure.

The vehicles in this road show, which are called plug-in hybrids, were Toyota Priuses retrofitted with large advanced battery packs that can be charged overnight and used to power the cars electrically for short trips. "If you look at how people typically drive cars, about half of the driving that you use gasoline for you could be using the electricity that comes out of your wall," says Martin Klein, CEO of Electro Energy of Danbury, CT, which developed the battery pack and control system for one of the cars on display in Washington. What's more, he says, the existing power grid means that "the infrastructure is all in place."

[Click here for some shots of plug-in hybrids.]

Ordinary hybrids get all their energy from gasoline, but they are much more efficient than conventional cars because extra energy from the engine and braking is stored in a battery pack, which powers an electric motor to boost acceleration and even fuel the car completely for short distances at low speeds. The boost allows hybrid automakers to use a smaller, more efficient internal-combustion engine without sacrificing performance. And hybrids also save gas by turning off their engines when stopped in traffic or at a stoplight. Overall, the fuel economy of a conventional Prius is around 50 miles per gallon.

Plug-in hybrids have a larger battery pack, which allows them to run on the electric motor much longer -- for 20-25 miles in the case of the Electro Energy car. The battery is charged from an ordinary electrical outlet. Thus, a commuter who drives 10 or 15 miles to work on city streets could recharge the battery at night and make the commute entirely on electricity. Others would need the gasoline engine at highway speeds, but could rely on the battery while driving in the city. When the energy stored up overnight runs out, the car slips into conventional hybrid mode until the next charge. This gives the vehicle an advantage over all-electric vehicles, which have been hampered by limited range due to limited battery storage capacity.

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Comments

  • What about grid strain?
    Guest (Sean) on 05/23/2006 at 12:00 AM
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    Maybe I'm being having a dense moment (it happens), but it wasn't too long ago we were hearing how strained the power system was by everybody's computers & air conditioners being on all the time. Wouldn't having lots of people plug their cars in all night be a bit of a problem here?

    (Okay, yeah, I know there wouldn't be a large percentage of the population buying these cars any time soon, but still.)
    Rate this comment: 12345
    • Plug In Hybrids
      Guest (Matt) on 05/24/2006 at 12:00 AM
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      Grid Strain is only an issue in peak times.  Off Peak night times are ideal for charging batteries. 
      Rate this comment: 12345
      • Grid strain
        Guest (Dave W) on 05/27/2006 at 12:00 AM
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        The point is valid. Similar experience in UK using heat storage systems that drew power overnight. Eventually peak load shifted as a result and consumers were stuck with unrealized savings because of increase in off-peak rates.

        My main concern would be that the electricity coming out of the plug is not really all that efficient from a thermodynamic point of view.
        Rate this comment: 12345
        • Excellent Points all Around
          Guest (Mark K) on 06/01/2006 at 12:00 AM
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          Let me add the cost, disposal, and related waste of the batteries themselves.
          Rate this comment: 12345
          • Re: Excellent Points all Around
            asdar on 08/07/2007 at 9:33 AM
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            The initial cost is high, and there are some small related waste, and those are valid issues. Anyone that's disposing of battery material should be shot and have their material disposed of.

            It can be recycled easily.

            Lithium isn't a hazardous material, however so it's not a threat even if someone is dumb enough to want to dispose of it.
            Rate this comment: 12345
    • Plug-in Hybrid Electrc Vehicles
      Guest (Paul McLachlan) on 05/24/2006 at 12:00 AM
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      The PHEV is undoubtedly the common vehicle of the future.  The technical challenge is power-density, for the battery pack, the ICE and the vehicle as a whole.  The size and weight of the ICE/generator unit will determin the range and performance just as much as the development of the ideal battery.  The high power density Pivotal Engine will make the difference.  see www.pivotalengine.com
      Rate this comment: 12345
      • Plugins
        Guest (Tim) on 05/24/2006 at 12:00 AM
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        the OPOC also seems a good contender. I do like the opposed piston approach. Light, smooth and compact.
        Rate this comment: 12345
    • What about grid strain?
      Guest (Paul) on 05/24/2006 at 12:00 AM
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      Uncontrolled charging of plug-in hybrids in the evening would be a problem if this was coincident with power levels on the local grid.  This can be addressed by offering time-of-use rates and an automatic control (i.e. timeclock) to initiate vehicle charge after the "peak" power period has passed.  However, this requires the local utility to install time-of-use meters so the consumer can be offered the lower electric rate.  A more Draconian measure would be to "allow" plug-in hybrid charging ONLY if you had an electronic time clock and not provide a discount to the consumer.  That would be nearly impossible to enforce although academically interesting to talk about.
      Rate this comment: 12345
    • While the country sleeps.
      Guest (Ned) on 05/24/2006 at 12:00 AM
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      Consider that the recharging takes place overnight, not during the peak consumption time caused by a/c use and office habitation.
      Rate this comment: 12345
    • grid strain?
      Guest (JAB) on 05/24/2006 at 12:00 AM
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      I agree with Ned that evening recharging is the lower grid utilization so that won't be a problem. Adding power to the grid, given its distributed nature, is a relatively well understood task. Overall, I would think the cost factor is a much greater barrier to adoption than potential grid strain.
      Rate this comment: 12345
    • grid strain
      Guest (Steve) on 05/24/2006 at 12:00 AM
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      Most cars would be plugged in at night when demand is low.  Also, battery charging only uses a tiny amount of electricity compared with say, a television or a home appliance.
      Rate this comment: 12345
      • Electric Draw
        Guest (Phil) on 05/24/2006 at 12:00 AM
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        I ran a calculation that confirms Priusmaniac's quote that it takes a little over 1kwh to go 5 miles.  That means that if you want to put 20 miles worth of charge in your battery you'll need 5kwh over the course of a night (1.2kwh/5 miles times 4, assume some inefficiency in battery, motor, etc.).  5kwh over an 8 hour period is 625 watts.  That's 2 to 3 times more power than my big screen tv uses. 

        This also amounts to 150 kwh over the course of a month.  Currently the average house uses about 700 kwh per month.

        So I disagree with your assertion that that draw is "tiny... compared to a television or home appliance."
        Rate this comment: 12345
        • Electric Draw
          Guest (Dick) on 05/24/2006 at 12:00 AM
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          The current Prius carries 1.7 KwH of NiMH battery.  If you added four more of these units, you'd be up to 8.5 KWwH, which would carry you for a 20-25 mile commute on battery power alone.  If you could recharge while at work, this translates to a 40-50 mile overall commute.
          Rate this comment: 12345
        • electric cost per kwh
          Guest (Arthur Bebell) on 05/26/2006 at 12:00 AM
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          My cost could be about$24.00 - $30.00 per month. I spend about $35.00 per month for regular gasoline driving my Buick Regal. Please tell me about my economy!
          Rate this comment: 12345
    • Off-peak can handle 80 million PHEVs
      Guest (SherryB) on 05/24/2006 at 12:00 AM
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      The off-peak, nighttime capacity of existing power plants could handle approximately 80 million plug-in hybrids before we'd need to think about adding a power plant. Details and more in my upcoming book, Plug-in Hybrids: The Cars that Will Recharge America.
      Rate this comment: 12345
    • Grid strain
      Guest (Patrick M) on 05/24/2006 at 12:00 AM
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      Tired argument... have you heard of solar and wind to charge your battery... geesh, doesn't take a rocket scientist!!!!!!
      Rate this comment: 12345
      • Solar & Wind -- Where is it?
        Guest (Phil) on 05/25/2006 at 12:00 AM
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        Another tired argument: Show me the solar panels and windmills that will do this recharging.  How well do solar panels work at night?
        Rate this comment: 12345
        • the new solar age
          Guest (bob) on 05/27/2006 at 12:00 AM
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          The new wave in solar tech can run at night. it relys on convection and heat stored in large salt water basins. at night the hot water can be pumped through the system to keep things going. the stored heat can also be used to vary the load during peek hours.
          its still in the prototype stage but its looks promising.

          http://www.wired.com/news/technology/0,1282,54917,00.html
          Rate this comment: 12345
          • My solar panels...
            burritos on 06/06/2007 at 3:07 PM
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            a 3.3KW system gives me about 10-17KW(off peak-peak season) a day. Because of net metering it basically turns the electrical meter backwards during the day and during the night it runs forward. So while I might not be using solar energy to charge during the night time, I can still get a net zero use of energy from the grid depending on how much electrical energy I might use outside of the car charging.
            Rate this comment: 12345
    • What about grid strain
      Guest (Dick) on 05/24/2006 at 12:00 AM
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      The great thing is that the recharging is done overnight when the load on the electric grid is the lowest!
      Rate this comment: 12345
    • Re: Grid Strain
      Guest (Jim) on 05/25/2006 at 12:00 AM
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      Sean, these PHEV cars would load the grid at night primarily. If some people were to charge during  peak load periods, the recharge would consume at worst 9 kWh, about the same as your portable heater on high for 6 hours.  By the way, at the national average electric rate of $0.085 kWh that is less than $1.00 a day for driving 35 - 50 miles.
      Rate this comment: 12345
    • potentially No grid strain
      Guest (J Young) on 06/02/2006 at 12:00 AM
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      The idea is to have the cars charge when we are in bed and the electric usage is low.

      Most power plants can't raise and lower output based on demand.  They have constant output.  Therefore, charging them at night would use power that would otherwise be wasted.
      Rate this comment: 12345
    • Re: What about grid strain?
      Susan K on 02/21/2007 at 11:05 PM
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      Add a lot of local solar and windpower to reduce grid strain.

      To keep from burning more coal, the next step should be solar powered garages at home to plug electric cars into.

      Imagine if malls and parking structures had solar panels on top, and sockets at every parking space so you could recharge during the day while at work, and in smaller topups while shopping.
      Rate this comment: 12345
  • Plug-In Hybrids
    Guest (Charlie Peters) on 05/24/2006 at 12:00 AM
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    Interesting but, how much profits generate from the Priuses? Made in Japan and China & helped with $thousands of tax generated welfare. The PR is helping Toyota sales but no profit from the car. 

    (510) 537-1796
    Rate this comment: 12345
    • Re: Plug-In Hybrids
      asdar on 08/07/2007 at 9:36 AM
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      It's not all about the costs, if it helps you can think of it as a large scale prototype that helps PR.

      We need a way out of oil, and this is one way that's sure to help and almost painless.
      Rate this comment: 12345
  • What about the costs?
    Guest (david) on 05/24/2006 at 12:00 AM
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    The beauty of the existing Prius is that it essentially recharges itself for "free" utilizing kinetic energy which would otherwise be thrown away.
    Are there estimates as to how much a "recharge" will cost even at off-peak rates?
    One needs to ask not just MPG but also MPD (miles per dollar - what the consumer looks at) and put gas and electricity into the same equation.
    Rate this comment: 12345
    • Reply to : what about the costs ?
      Guest (Priusmaniac) on 05/24/2006 at 12:00 AM
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      The cost of electricity is only one factor. It depends on where you live and at what time of the day you buy it, but it goes from 2 to 18 cent/KWh. With a 5 miles/KWh Prius efficiency, that amounts to 0.4 to 3.6 cent/mile.

      The other factor is gasoline price, that goes from 190 to 700 cent/gallon according to where you live, be it Dubai or London. This equals for a 50 mpg Prius to a range of 3.8 to 14 cent/mile.

      From this it becomes obvious that even in Dubai, you gain in operating costs by driving with electricity.
      Rate this comment: 12345
      • what about the costs ?
        Guest (rbh) on 05/24/2006 at 12:00 AM
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        The grid is no more than 50% efficient after transmission.
        After power plant and battery cycle efficiencies 'plug-ins' are NOT more effective than direct gasokine engines. The cost estimates above need about a 3X multiplier !
        So while the cars could run on 'coal' that would be the extent of the gains, poluting (and CO2 at the power plant site instead of the city.   This is a small effect with Pzf cars !!!
        Rate this comment: 12345
        • Reply to rbh
          Guest (Priusmaniac) on 05/24/2006 at 12:00 AM
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          David’s question was how do gasoline and electricity compare in cent/mile, nothing else. What he wanted to know was what would be the difference for him, in his own pocket dollars.

          On the other hand, the question that you raise has already been answered by Professor Andy Frank of the University of California at Davis, even in the worst case scenario of electricity produced from coal an electric vehicle is still producing less CO2/mile then a standard car.

          In the case of the Prius that difference is lower, but because the plug-in package also improves the regen capability of the car, it still exist. Especially in the hills or on mountain roads where much regen must be done.
          Rate this comment: 12345
        • How efficient...
          burritos on 06/06/2007 at 3:17 PM
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          is it to go to war for oil, to deal with muslim countries who's people hate us and buy their oil, to ship oil, etc...
          Rate this comment: 12345
    • Costs
      Guest (Aymeric) on 05/25/2006 at 12:00 AM
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      I agree totally. Everybody acts like the electricity from the wall outlet is free. it is neither free to the consumer nor free of added carbon to the environment. Electricity has to be produced after all.
      Rate this comment: 12345
      • Re: Costs
        asdar on 08/07/2007 at 9:44 AM
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        It is really shortsighted to blame the car for the source of electricity. This isn't a case of the chicken or the egg. Electric cars have zero emissions, if you choose to power them from bad sources that's not the cars fault.

        What is like the chicken and egg is that if we have the cars, then making more solar/wind and other alternatives makes more sense, because we'd have the storage to make better use of it.
        Rate this comment: 12345
  • 100 MPG?  I don't think so...
    Guest (Phil) on 05/24/2006 at 12:00 AM
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    It's dishonest to claim 100+ miles per gallon in this car by discounting the primary fuel used to create the electricity used while plugging in.

    With regard to cost, Priusmaniac under quoted the range of the cost of electricity.  A kWh in my area already costs 20 cents, and I know I don't live in the most expensive power region in the US.  Other countries as a whole pay as much as 30 cents.
    Rate this comment: 12345
    • 100 MPG? I don't think so...why not?
      Guest (J Young) on 06/02/2006 at 12:00 AM
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      Ok.  It gets 100+ mpg of gasoline.

      Yes it takes fuel to produce the electricity to charge the batteries but that is usually not oil.  It also takes energy to transport oil and refine it.  How much I don't know.

      By the way, my electricity costs between 3 and 9 cents per kwh depending on how much I use.
      Rate this comment: 12345
  • 100 MPG
    Guest (KB) on 05/24/2006 at 12:00 AM
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    Of course electricity costs vary, but I've seen estimates that an overnight charge could cost between 50 cents and a dollar.  The battery packs' capacities are in the neighborhood of 7kWh, so you can do the math based on your local rates. A dollar for 25 miles is better than you can get with gasoline now.
    But the main advantage of plug-ins could be reducing dependence on oil
    Rate this comment: 12345
    • Overnight charges
      Guest (Phil) on 05/24/2006 at 12:00 AM
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      As others have pointed out, there is little to no hardware in place currently to differentiate electricity bought at night from any other time of the day.  This means that there are significant infrastructure costs to taking advantage of off peak rates.
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      • time of day pricing
        Guest (Greg) on 05/24/2006 at 12:00 AM
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        My house has had a time-of-day electrictiy meter for 25 years now (and I have different rates according to when the electricity is used).  I think it's fairly common in my area (MD).
        Rate this comment: 12345
    • Redistribute the cash flow
      Guest (ReubenDenver) on 05/24/2006 at 12:00 AM
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      Reducing the dependence on foreign oil would also reduce the profits inside oil companies.  Shifting cash flow from oil companies to battery mfrs and electric companies (coal) will meet resistance.  There is a TON of oil money in DC.
      Consumers would be faced with higher up front costs for vehicles.  They are also the first to want 100MPG AND the first to demand warranty repairs if those batteries and recharging systems don’t perform ( more risk for Honda – the other hybrid Mfr- I love my Honda!)
      So where is all the Freedom Car and PNGV money going? Maybe our tax dollars should be shifted to reward patents on batteries or tuition for continuing education of physical sciences ( math, chemistry, physics…)
      PHEV need better batteries and that has been the mantra ever since California tried to push EV’s .  Don’t hold your breath!
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      • Consumers are smart AND frugal
        Guest (Christi in Toledo) on 05/24/2006 at 12:00 AM
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        I concur with ReubenDenver wholeheartedly.  He's brilliant!
        Upfront costs for PHEVs will deter all but the yuppies and the EV lunatics who will pay anything to say they are driving only with electricity.  Most people will do the math and realize the cost savings will never exceed the initial costs.  And unfortunately not too many people really care about the environmental benefits over the impact on their pocketbooks.
        Research money needs to be put towards much much better battery technology to increase life, reduce weight, and reduce cost, before PHEVs or EVs will be successful.  Sorry EV fanatics!  Reality bites.
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        • up front costs
          Guest (William Millard) on 05/25/2006 at 12:00 AM
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          Perhaps we should levy a tax on low mileage vehicles to subsidize the purchase price of high mileage vehicles?
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          • Gas Tax
            Guest (Phil) on 05/25/2006 at 12:00 AM
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            We already do, it's called the gas tax and is applied in direct proportion to miles driven per gallon.
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            (