Plug-in hybrids: Lots of room

Hybrids connected to the electrical grid could change the energy game 16

The U.S. Department of Energy has concluded that the existing U.S. electrical grid -- without additional construction for generation or transmission -- could accommodate 180 million cars that draw their power from night-time (off-peak) electricity. That's about 85% of the cars in the country.

The full report is not yet available, but based on the press release, there's lots of good news -- with some bad news mixed in.

First, the good news: aside from dramatically lowering U.S. oil imports and keeping that money inside U.S. borders, grid-connected cars would marginally improve air quality. Even though no new coal plants would be needed to accommodate the cars, existing coal and natural gas plants would be run at greater capacity. This means what should be an easy plus for the environment is, at best, a marginal gain. Instead of the double-digit declines in sulphur and CO2 emissions, we get a measly 5% CO2 decrease, and an actual increase in sulphur.

Still: air quality in urban areas would improve substantially from the lack of tailpipe emissions.

One researcher is quoted saying that because electricity sales would increase without additional capital expense, prices per-kilowatt-hour could go down. I'm skeptical on that last count.

Something the press release itself doesn't deal with is the potential for vehicle-to-grid services. This is where electric cars (either hybrids or full EVs) have the potential to be a real-life silver bullet. Anyone who advocates for increased use of renewables is inevitably confronted with the problem of intermittency. With wind, the rule of thumb is that if grid energy supplied by wind grows to more than 25-30%, utilities need to spend prohibitive amounts on "spinning reserve" to even out supply.

Well, a nation driving plug-in hybrids makes for a spinning reserve of amazing proportions -- according to one estimate (PDF), the U.S. fleet would power the U.S. electrical grid seven times over.

This means plug-in hybrids (or eventually full-blooded EVs) finally eliminate the fundamental barrier to solar and wind electricity. They will make wind more competitive than it already is. And as the cost of solar comes down (see Bradford, Travis), it will have a massive reservoir to dump electrons into, without the actual unsightly reservoirs we currently build for hydro dams.

All of this requires the kind of smart grid Al Gore and David love so much, as well as a great deal of foresight by policymakers. Luckily, the utility lobby is actually on the right side of the issue for once, and The Mustache is on our side too. Even GM and Ford are promising plug-ins.

Environmentalists, even more than most groups, have good reason to be suspicious of technical breakthroughs that purport to solve our problems. But between rapidly declining solar and wind costs, a new crop of electric vehicles entering the market in the next few years, and a strong consensus in the U.S. today that things need to change, I'm thinking the V2G concept is a no-brainer.

John McGrath is an intinerant student and sometimes reporter currently living in Toronto, Canada. He mainly writes about Canadian and International Politics from an energy and climate perspective

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  1. JMG's avatar

    JMG Posted 3:57 am
    12 Dec 2006

    Not so fastOK, so assuming it takes zero energy to build 180M plug-ins, it might be possible to show a 5% CO2 drop -- COMPARED TO BUSINESS AS USUAL if those cars stay all-petroleum, where BAU is defined as ever more miles driven by ever more people.
    Moreover, this just perpetuates the problem of shifting outputs from visible criteria (regulated) pollutants to invisible nonregulated ones--the kind of thing that led Gregg Easterbrook down the garden path to believing that the environment was getting better and better even as it was coming closer to the abyss.
    We have to stop having these discussions refer to unspecified comparisons (which are really to BAU).  Everything needs to be referenced to what the best science can tell us must happen to avoid the worst calamities:  75% reduction in absolute CO2e.
    To get this measly 5% reduction (against BAU-- which means probably no net reduction in reality) would, nevertheless, soak up immense pools of capital that we need to be putting into mass transit and relocalization efforts to ELIMINATE TRAVEL AS AN ESSENTIAL FEATURE OF DAILY LIFE.  That's the only way we're going to get there.
  2. Biodiversivist's avatar

    Biodiversivist Posted 4:19 am
    12 Dec 2006

    JMGThe article lays out another way. Big batteries in cars could make wind and solar cheaper than coal (providing a free place to store energy, thus doubling their cost effectiveness (a 100% improvement). If you replace coal plants with these, you get your 75% reduction and then some.

    In the end, it all comes down to biodiversity. Help acquire and protect ecological hotspots, give to a conservation organization: http://www.saveourbiodiversity.com
  3. John McGrath Posted 4:46 am
    12 Dec 2006

    ExactlyThe point is not that PHEV's are the answer to our prayers, but that PHEVs, wind, solar, and (maybe) biofuels work together much better than any one element by itself.  PHEVs can provide the vital service (storage) that renewables need, in a product that people will actually want - PHEVs will, generally speaking, already be far more fuel-efficient even on liquid fuels, and will save further $s by running mostly on electricity.
    And you definitely don't need to sell me on efforts to reduce the role of cars in the North American lifestyle.  But there are 200 million cars already.  Even if we halve that amount -- which is unrealistically draconian, especially considering future population growth -- we've still got 100 million cars, and something useful for them to do.
    The distributed storage that PHEV's represent could actually help relocalization, couldn't it?
  4. sunflower's avatar

    sunflower Posted 4:47 am
    12 Dec 2006

    CaveatsBig batteries and ultra capacitors will not make solar and wind power cheaper... dispatchable and useful -- yes, cheaper -- no.  Solar (and maybe wind) are already cheaper than fossil fuels w/o subsidies.  
    The transition will not happen until the existing coal and oil machines are broken beyond repair, or not until the existing fuels become extraordinarily expensive.

  5. John McGrath Posted 5:05 am
    12 Dec 2006

    caveats accepted, with one quibbleNot an economist, but I suspect sunflower's right about costs.  One general question:  The cost (in terms of $/kwh) of solar and wind currently needs to take in to account intermittency, and the reality that some electrons will never make it to the grid.  Some watts will be produced at times when the grid can't handle it.
    Assuming the storage exists, wouldn't that lower the price marginally, as renewables would be able to operate until the storage was full?
    Obviously, not a huge price decline.  But wind is already profitable vs coal and natural gas in Texas and other states.
  6. sunflower's avatar

    sunflower Posted 5:57 am
    12 Dec 2006

    Good Samaritans & dress codeSolar and wind power will not have the impact that air conditioners have until after some $50 billion.  The load on the grid changes all the time.  Changing loads change fuel burn rates at power plants, and spinning carbon plants come on & off line.  Solar and wind power are not "all or nothing" propositions.  The target is carbon reduction.
    Solar energy is cheaper than fossil fuels for much more diverse markets than just electricity, such as displacing carbon fuels for heat, hot water, cooling, industrial process heat (huge), and something weirdly called "repowering" where solar collectors displace fuels at power plants with boiler preheat systems.
    The public head-in-hand manner of replacing infrastructure with look-a-like alternatives is nuts.   I see it in Cassandra's soy meals that are made to look and taste like meat, in my Prius gear shift knob (just a computer switch) that looks and feels like a mechanical gear shift lever, in ethanol that looks and burns like gasoline, in solar energy that looks and acts like power from coal, in electric motorcycles that have sound generators to sound like internal combustion engines, in Christmas trees that look like Pagan trees...
  7. Biodiversivist's avatar

    Biodiversivist Posted 6:30 am
    12 Dec 2006

    True. Let me fine tune that argumentIf you have a solar grid that can only produce power half of the day, a coal plant has to take up the slack the other half. If you double the size of the solar plant, so that it uses half of its  capacity to  charge batteries, you can get rid of the coal plants (or at least more of them). This huge spinning reserve will allow the  replacement of more coal plants, which are more expensive to operate. This is how the usefulness  you describe also translates into cost savings. It makes solar power that much more efficient in  terms of being less intermittant

    In the end, it all comes down to biodiversity. Help acquire and protect ecological hotspots, give to a conservation organization: http://www.saveourbiodiversity.com
  8. caniscandida Posted 6:43 am
    12 Dec 2006

    "pagan trees"?You mean, the Christian custom of cutting down an evergreen tree in December and putting it in one's house has a pagan origin?  OK, sure enough.  But what symbolism did those old Germanic types assign to those trees, I wonder?

    Chickens are our cousins!

    So are other sensitive animals!

    Enough is enough!

    No more factory farms!
  9. sunflower's avatar

    sunflower Posted 6:53 am
    12 Dec 2006



    Not Gods of Rome
    From my dim memory, the Pagans left the decorated trees living in the forests.  
    The Christians adopted the solstice celebration so that the new religion had a look-a-like flavor of a very old and established tradition.

  10. wiscidea Posted 7:21 am
    12 Dec 2006

    transmission losses and national securityPerhaps someone can eliminate two concerns I have or direct me to a suitable source of information.
    I'm very skeptical about the advantages of electric cars drawing power from the grid.
    (1) How do transmission and distribution losses of electricity, which are about 7%, fit into the equation? If a power plant depended on natural gas, for example, would it not be better to power cars directly with natural gas or some derivative of natural gas? What about coal? Would it not be more efficient to convert coal to a fuel that can be used for cars? It seems there is too much faith in the notion that the bulk of our electricity will be coming from wind and photovoltaics and that we will produce enough to offset transmission losses.
    (2) Depending on a few power grids is a serious threat to national security. I view distributed power generation as one of the major advantages of wind and photovoltaics, especially if the energy can be stored in some way. We would be in a better position to withstand and recover from a terrorist attack, natural disaster, manipulation of the market, or simple ineptitude. Gee... what are the odds of 3 or 4 of these occuring under a single U.S. Presidential?
    Already dependent on a few power grids that might be brought down by a determined individual or natural event, do we really want our tranportation system also dependent on those grids?
    Right now I'm trying to imagine evacuation of an area severely damaged by a large storm... not only is the power out, not only are radio stations off line, not only are there delays in getting help to the people, but FEMA forgets to make sure the vehicles necessary for evacuation are fully charged and tries to save money by not have extra energy storage capacity available.
  11. sunflower's avatar

    sunflower Posted 8:39 am
    12 Dec 2006

    Flogging a dead car.We all talk about what we (or they) should do, like what we think or blog will make any difference.  In reality people will do whatever it takes to get the job done, and to hell with the externalities.
    I do not believe the real threat is a natural disaster, terrorism, or grid collapse.  
    Why do we travel?  Mostly for social interaction, entertainment, jobs, and because we can.  All those reasons may change long before the oil runs dry and the climate tips over.  We are facing a dollar collapse (the China delegation), a war with Iran (oil surplus dollars have tripled since 2002), and emerging problems still in the dark.  The self destruction of the global consumer economy is certainly one possible delay for the global warming problem.
    The more likely threat comes from old age, leaving the young with a real mess.  Survival will dominate what the young people do.  I have a few more years to leave some pearls of experiences.  In the end, it is up to the young to organize for survival.  In your cash-short world, there will be many carpools in old clunkers, more passengers using mass transit, and much less travel.
    In a stable unchanging world wiscidea is correct to question the thermal dynamics of power plants used for transportation.  It runs contrary to shutting these monsters down. Natural gas will be replaced by coal and coal is burned more efficiently at power plants than oil made from coal burned in cars.
    Solving this problem of fueling cars is another example of solving a problem with something that looks like what we have become accustomed to.

  12. Gar Lipow's avatar

    Gar Lipow Posted 9:34 am
    12 Dec 2006

    Transmission losses and national security1) Does an electric vehicle save emissions? Yes - even with our current grid. For every 100 units of fossil fuel burned on our grid you get back 36 units of electricity - even after transmission losses. (And this is strictly for fossil fuel output, and does not include hydro and nuclear).  Now part of that generations is coal that puts out 20% more carbon that oil. But part is natural gas that puts out about 20% less than oil. And part of course is nuclear that has much lower carbon emissions (though with lots of other problems), and hydro which is in dispute. After you put that electricity into a battery and take in out again you transform about 70% to 75% into mechanical energy. So between 25 and 27 units of mechanical power for each 100 units of fossil fuel you burn in a power plant, probably a bit more because of the low carbon sources in the mix.
    With a gasoline IC engine you only get about 15 units of mechanical energy  for each 100 units of fuel. A hyrid can boost this to 20% at most. So running directly off the battery gives you almost double the efficiency of a normal gasoline engine, and about 25%+ more than a hybrid.  A non-hybrid diesel can match this. But of course as we lower the carbon cotent of the grid you get much bigger improvements. For example, if natural gas and wind were substituted for all of the coal, running off battery would halve the emissions compared to a hybrid.
  13. Jason D Scorse's avatar

    Jason D Scorse Posted 1:28 pm
    12 Dec 2006

    I think this would be great...also, cars would last longer since so many mechanical parts wouldn't be required and once we get large scale wind & solar we could get even bigger emissions reductions. By the way, I'm an envrionmentalist who is not the least skeptical of technological fixes- we're living proof of the great power of technology as we type away on the internet...

    J.S. teaches environmental economics and blogs at http://www.voicesofreason.info.
  14. Gar Lipow's avatar

    Gar Lipow Posted 1:50 pm
    12 Dec 2006

    Tech fixes>also, cars would last longer since so many mechanical parts wouldn't be required and once we get large scale wind & solar we could get even bigger emissions reduction.
    Especially if we did a Hypercars - either aggressive or true EV. In either case we can reduce moving parts in the car to around twenty. Also add ultralight carbon-fiber/kevlar composite bodies and reduce emission further. Even if solar or wind electricity costs much more than gasoline or diesel does today, Hypercars will use that electricity so efficiently they will still cost no more to run that conventional cars do today, probably less.
  15. wiscidea Posted 1:03 am
    13 Dec 2006

    thanks for the reminderI forgot about the feedback loop that makes automobiles even more efficient once you get rid of the gasoline powered engine.
    Paul Hawkins describes this quite well in one of his books. Lighter motor... lighter car... reduced material for steering and braking mechanisms... further lighter car... requires less power... further smaller engine... more interior space... reduces overall size of automobile... room for better safety devices...  improved performance... less maintanence... reduced cost... et cetera.
    Thanks for the morale boost.
  16. Gar Lipow's avatar

    Gar Lipow Posted 6:55 am
    13 Dec 2006

    Paul Hawkins>Paul Hawkins describes this quite well in one of his books. Lighter motor... lighter car... reduced material for steering and braking mechanisms... further lighter car... requires less power... further smaller engine... more interior space... reduces overall size of automobile... room for better safety devices...  improved performance... less maintanence... reduced cost... et cetera.
    Natural Capitalism perhaps? And it even works for hybrid gasoline powered Hypercars. The original idea behind the hybrid Hypercar was that 100% of the power was electrical. It is just that most of the electricity came from a small gasoline engine. Because he gasoline engine is used only to drive the electric motor (never for direct drive), you would use a very small engine and a very small gas tank. So you still had the reduction in parts, light weight, all the feedback cycles you mentioned.
    On the other hand, you still have the bottleneck of that IC gasoline engine. While you have huge gains from reducing weight and wind resistance,you still are not going to get more than 20% of the heat value of gasoline as mechanical energy from a gas IC engine. (And even that 20% is an improvement over the 15% limit you have with direct drive.)

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