EarthTalk: Are hybrid cars really better for the environment?

Mar 30, 2009 By E/The Environmental Magazine

Dear EarthTalk: If you have an electric or plug-in hybrid car, you're paying for electricity rather than gasoline all or most of the time. How does that cost compare to a gas-powered car's cost-per-mile? And since the electricity may be generated from some other polluting source, does it really work out to be better for the environment? (Kevin DeMarco, Milford, Connecticut)

When you compare battery to gasoline power, wins hands down. A 2007 study by the nonprofit Electric Power Research Institute (EPRI) calculated that powering a plug-in (PHEV) would cost the equivalent of roughly 75 cents per gallon of gasoline -- a price not seen at the pump for 30 years.

The calculation was made using an average cost of electricity of 8.5 cents per kilowatt hour and the estimated distance the car would travel on one charge, versus a car that gets 25 miles per gallon and is powered by $3 per gallon gasoline. Change any of those variables and the relative costs change. For example, substituting a car that gets 50 miles per gallon doubles the comparative electrical cost (though it still works out much cheaper than gasoline). On the other hand, in some areas where wind or hydropower is wasted at night -- just when the PHEV would be charging -- the utility might drop the kilowatt hour cost to two to three cents, making the charge much less costly.

And don't worry that we'll run out of electrical power: A 2005 study by the U.S. Department of Energy's Pacific Northwest National Laboratory estimated that three-quarters of the country's current small vehicle fleet could be charged by our existing electrical grid without building new . (And if all those cars were replaced by PHEVs, it would eliminate the need for 6.5 billion barrels of oil per day, or 52 percent of current U.S. oil imports.)

Regarding environmental impact, charging up your car with electricity from the grid also wins handily over filling up at the gas station. In the most comprehensive PHEV study to date, released in 2007 by EPRI and the nonprofit Natural Resources Defense Council (NRDC), results predict that all greenhouse gases will be reduced as PHEVs begin to penetrate the car market. Estimated cumulative greenhouse gas reductions from 2010 to 2050, depending upon how fast PHEVs take hold, range from 3.4 to 10.3 billion tons.

More than one half of our national energy grid is powered by coal, and in areas where PHEVs are charged through coal-provided electricity, says NRDC, there is the possibility of increased levels of soot and mercury emissions. However, charging up can be much less of a guilt-ridden affair where cleaner electrical sources like wind and solar are available. The website HybridCars.com points out that as more power plants are required to develop green power and emit fewer greenhouse gases, the environmental and health benefits will further increase.

___

GOT AN ENVIRONMENTAL QUESTION? Send it to: EarthTalk, c/o E/The Environmental Magazine, P.O. Box 5098, Westport, CT 06881; submit it at: emagazine.com/earthtalk/thisweek/, or e-mail: earthtalk(at)emagazine.com.

___

(c) 2009, E/The Environmental Magazine
Distributed by McClatchy-Tribune Information Services.

Explore further: Climate change and air pollution will combine to curb food supplies

add to favorites email to friend print save as pdf

Related Stories

Study: Are plug-ins the next wave of hybrid vehicles?

Sep 25, 2007

Is America ready for rechargeable cars? Teams of researchers at the University of Michigan and Pacific Northwest National Laboratory will explore this question and others with $2 million from the U.S. Department of Energy's ...

UC Davis Will Study Users of New Plug-in Hybrid Cars

Oct 30, 2007

The latest green car goes under the UC Davis microscope today: a hybrid sedan modified to recharge from a standard 110-volt electric outlet. It can travel as far as 20 miles on batteries before drinking a drop of gasoline, ...

U.S. company reveals hybrid car plans

May 05, 2006

The AFS Trinity Power Corp. of Seattle filed a patent application Thursday disclosing the company's new technology for its Extreme Hybrid car.

Recommended for you

Australia approves huge India-backed mine

4 hours ago

Australia has given the go-ahead to a massive coal mine in Queensland state which Environment Minister Greg Hunt said Monday could ultimately provide electricity for up to 100 million Indians.

Phytoplankton use turbulence to survive

6 hours ago

A unique water profiling instrument developed by The University of Western Australia's Centre for Water Research (CWR) is enabling scientists to understand the impact of even the most subtle turbulence on ...

User comments : 16

Adjust slider to filter visible comments by rank

Display comments: newest first

deatopmg
3.3 / 5 (8) Mar 30, 2009
this is only half the story. When one takes into consideration that electric vehicles or hybrids over their life-cycle are far more damaging to the environment to build and recycle than IC driven vehicles a totally different story emerges.

Consider the source of this report: the end justifies the means (half truths).

And not included in the costs are the state and federal road taxes that are used exclusively for infrastructure maintenance.
CreepyD
4.9 / 5 (8) Mar 30, 2009
So this is saying you use less electricity and produce less CO2 burning fossil fuels to make electricity and then powering the car with that than powering the car directly from the fossil fuel?
A_Paradox
3 / 5 (6) Mar 30, 2009
... consideration that electric vehicles or hybrids over their life-cycle are far more damaging to the environment to build and recycle than IC driven vehicles ...


Firstly, I would like to see a justification of that broad general assertion. I don't see why the construction of a hybrid car should entail greater entropy than an equivalent petrol, diesel, or LPG fuelled vehicle. I think a bigger issue is the need to construct motor vehicles out of wood, aluminium, recyclable plastics, etc. rather than rusting iron that must be painted with toxic paints and sealants.
A_Paradox
4.4 / 5 (7) Mar 30, 2009
So this is saying you use less electricity and produce less CO2 burning fossil fuels to make electricity and then powering the car with that than powering the car directly from the fossil fuel?


I agree there is a big question here; so much depends on the unspoken assumptions underlying the writer's thinking. I think the energy payoff may come from the economies of scale in the production process, and in the ability of hybrid or all electric cars to recover braking energy. I suspect that further efficiencies can be had from utilising the above-ambient temperature of power station cooling water. This can be done using Stirling engines which appear to be on the way back into favour.

Other things to think about are:
* many trips that people make in cities could be done just as easily by bicycle, with great health benefits due to the exercise,
* we have been committing a grave error in calling rock oil and coal "fossil fuels"; far better terms are "liquid and solid, or gaseous, fossil hydrocarbons", because these fossil substances could [still] and should be seen as non-renewable capital resources capable of providing complex carbon chain molecules for production of recyclable plastics, etc, for many 100K years.
* nuclear [check out the Adams Atomic Engine web site for example] could provide relatively cheap and non-polluting electricity generation for the hundred years or so needed to create a totally renewable electricity generation infrastructure.

It's all do-able!
lengould100
3.3 / 5 (8) Mar 30, 2009
Two other points: 1) Fueling an auto directly with fossil fuel provides no means to possibly capture and sequester the CO2 emitted. 2) Even with T&D losses and battery / charger losses, central generation and electric drive transport is potentially more fuel-efficient than IC engines. eg. gasoline engine max 25% efficient, with idling / braking etc. typically 12.5% net energy efficient) vs. central IGCC turbine coal station 55% - (5% T&D * 55/100) = 52.4% - (10% chargers & battery * 52.4/100) = 47.16 - (15% drive system losses * 47.16/100) = 40.08% overall system effic. Then, if Carbon capture / sequestretation added, -25% effic. hit result overall = 30.06% effic overall, STILL significantly better than the 12.5% overall effic. of the gasoline engine which cannot ever do Carbon Capture and Sequestration.
david_42
4.5 / 5 (6) Mar 30, 2009
Although I've seen many allegations that electric cars are more damaging to the environment, I have yet to see any data. Given that there are only a few electric cars on the road, none of which have reached the end of life or even end of battery life, where do these opinions come from? You can't count the EV1s, they were still going strong when GM killed the product.
Doug_Huffman
3 / 5 (9) Mar 30, 2009
Read the life history of the Pious battery and think of integrating the change in pollution from old/low tech needed infrastructure to the new/high tech infrastructure required for this, or any, green-tech boondoggle.
Mayday
4.5 / 5 (6) Mar 30, 2009
Wouldn't any proper comparison looking for the best option pit the costs of building a brand new electric vehicle against the costs of fully utilizing an already existing, used IC vehicle. We have many millions of already built vehicles that have very long and useful lives ahead of them if properly maintained. It is a false comparison to just assume the junking of all these ready-to-go transportation resources.
I know it's a wild and radical thought, but the best solution might not be a BRAND NEW car.
Egnite
3.4 / 5 (5) Mar 31, 2009
Ahh, how nice the thought of clean streets would be, well until a 30yo bus grumbles past and smokes everyone out

It seems like a waste to create electricity at a power station then trasfer it to vehicles but it'll surely be much better for our streets and health in the long run! When are the electic busses coming tho? Guess we'll have to resort back to trams in the cities to become fully green?
lengould100
4 / 5 (5) Mar 31, 2009
When are the electic busses coming tho? Guess we'll have to resort back to trams in the cities to become fully green?


Visit Toronto. Has used electric buses forever. They have twin overhead trolley connectors which feed current from a pair of continuous wires suspended over the street. Quiet, efficient, regenerative braking for stops. Occasionally the driver needsto get out and re-set the trolleys onto the wires if it bounces off, but not very often, eg. I've rarely seen it. Excellent system.
Velanarris
4 / 5 (4) Mar 31, 2009
The problem with plug-ins, aside from the need for very rare metals like palladium, which are horribly environmentally unfruendly to mine, is the fact that plug ins don't conform to the infrastructure we already have in place.

Think on it this way. You're late for work, had a long day at work yesterday, you hop in the car and....

no juice, you're screwed. It'll be 12 to 14 hours before you can drive anywhere.

Now if this is a gasoline or diesel car you can push it to the local station, or walk over and grab gas, siphon from a neighbor, or maybe you have some gas stored, in any event once you have the gas, a few minutes and you're off.

Now that's going to be a rare occurance but it's one of the many ways in which plug-ins don't work for our societies.

There are many ways to change society to make plug ins work but that's not going to go over well with the majority.

There are many ways to change cars that suit society as is and fulfill the ecology friendly role. ie: Hydrogen cars are a big one. They use the same mechnics as our current gas pumps, and jsut like a diesel of petrol engine, a few minutes, and you're ready to go.

Now my comments don't get into hydrogen economy, or the materials that are used to make the systems (from all I've read they're very similar to hybrids and plug in's, meaning unfriendly rare earth metals), but if you want to change our fossil fuel use the best way would be to create a system through which we can use the infrastructure in place. It would have a few benefits, the least of which being lower cost to switch over and an easier, friendly transition.
GrayMouser
2.5 / 5 (4) Mar 31, 2009
... consideration that electric vehicles or hybrids over their life-cycle are far more damaging to the environment to build and recycle than IC driven vehicles ...


Firstly, I would like to see a justification of that broad general assertion. I don't see why the construction of a hybrid car should entail greater entropy than an equivalent petrol, diesel, or LPG fuelled vehicle.

Take a look at the cost of the process from ore to car, the energy required to process the ore, the areas the ore is available in, how the ore is mined, the life span of the vehicle, and the disposal of said vehicle.
Then compare it to an existing gas powered vehicle over it's lifespan (which in a few cases has been 100 years.)
I think you'll find that the hybrids don't have the actual (as opposed to that desired by the manufacturer's) life expectancy of a gasoline powered vehicle. Even now Prius owners will be looking at a battery replacement interval of 3 to 5 years.
Velanarris
4 / 5 (4) Mar 31, 2009
And it's amazing how much stuff is in that battery that can't be reused or reconditioned when it's "recycled".
sn0wman
4 / 5 (4) Apr 04, 2009
It's unfortunate the author doesn't mention the fact that nuclear would be a perfect source of electricity for electric vehicles.
Nartoon
4 / 5 (4) Apr 04, 2009
And when will hybrid/electric cars be able to travel the interstates for hundreds of miles in the same day?
la7dfa
2.7 / 5 (3) Apr 05, 2009
If we had a common battery module for cars, you could just stop and swap one in seconds? Would make it possible to drive 24/7 until we get a better source of energy.