Who Really Killed the Electric Car?Posted on January 4th, 2007 3 comments
It seems that in order to provide news or information that both stimulates and entertains, it’s necessary to present the facts so that when you’re done telling the story, there’s no doubt in audience’s mind who is praiseworthy and who is guilty. When you’ve rounded up all the suspects and made your accusations and assigned blame, you need to have the audience to feel totally convinced, self-righteous, and indignant about some obvious injustice. If you present both sides of an argument and try to remain neutral, it leaves the audience confused, emotionally conflicted, and feeling like they didn’t learn anything useful. Worse yet, you’ve lost out on an opportunity to recruit activists to your cause. This biased approach to some of the news shows and so-called documentaries is the secret to the mass appeal of entertainment shows that masquerade as ‘news’. I’m talking about shows like 60 Minutes, or 20/20 and, of course, anything ever made by Michael Moore.
And so it is with the movie, ‘Who Killed the Electric Car‘. The film’s creators have appointed themselves as judges, jury, and executioners of a whole slate of perpetrators, including not only the usual suspects, namely, our government and the clueless and greedy corporations, but also the majority of the film’s potential viewers.
As an engineer, I’ve often wondered when the internal combustion engine would be replaced by something more efficient and environmentally friendly, and it would seem that the electric motor would be just the ticket. An electric motor is simpler and more efficient than an internal combustion engine and doesn’t require nearly as much periodic maintenance.
An internal combustion engine wastes about 70% of the fuel’s energy content because it produces so much waste heat in the process of providing the mechanical work. About half of the waste heat goes out the tailpipe and the other half is removed from the engine via its cooling system. An electric motor only wastes about 10% of its energy as heat. So you’d think that electric cars with 90% efficient motor would have replaced 30% efficient internal combustion engines a long time ago, but they haven’t. Why not?
In the movie, Who Killed the Electric Car, the writers would like you to think that it’s a result of greedy corporations and conspiracies between the government, Big Oil, and car manufacturers, but in reality, those entities cannot control whether or not a technology is adopted by the public. That same conspiracy would have to occur simultaneously in every country in the world. You cannot legislate principles of physics into existence, although sometimes you can take credit for it when the laws are passed at the same time as the technological innovations that allow them to be implemented. A law to mandate adoption of technology that doesn’t exist, or technology that isn’t practical, is doomed to failure.
The failure of the electric car to capture an economically viable share of the market is due to it being a 90% solution, that is, it solves 90% of the transportation problem, but falls short in the critical 10% of transportation needs that are solved by conventional cars. It’s the ability to fulfill the critical 10% needs that often determines the success or failure of a product.
For example, it’s very common to see people commuting alone in vehicles that will comfortably carry 4 adults. Is the solution to that problem to force people into carpools or to require them to drive a 1 or 2-seat vehicle unless they can fill the other seats during their commutes? The problem with a 2-seat vehicle is that sometimes a person needs 4 or more seats, and a vehicle that has only 2 seats is of no use to them when that need arises. The additional cost of the fuel required by a larger vehicle that has extra seats is offset by the convenience of having them when they are needed.
Consider the often maligned SUV. Most of them have more capacity than their owners need 90% of the time, but when a person needs that space, which may only be a few times per year, the SUV can handle it. Also, even though your need for the SUV’s 4WD feature may be required a few percent of the overall driving time, it really pays for itself when it allows you to get home safely instead of being stuck by the side of the road in a driving snowstorm.
An electric car has limited range because its batteries have less than 1% of the energy density of gasoline. And it takes hours to recharge them vs. minutes to fill a gasoline powered car. Granted, 90% of your driving may fall within the range of an electric car on a daily basis, but what happens when you want to take it on vacation where you may be driving 2 or 3 times that range in a single day? The vehicle would be of no use to you in that situation.
One of the biggest driving forces behind the electric car is ostensibly its more favorable impact on the environment. It’s often called a “zero emissions” vehicle. Greenhouse gases such as carbon dioxide and its effects on global warming are cited as the major concern. Carbon dioxide is a byproduct of the combustion process of hydrocarbon fuels and the majority of electricity generation also produces this same greenhouse gas. There are a few ‘renewable’ sources of electric energy such as solar, hydroelectric, and wind that produce no greenhouse gases, but they account for a very small portion of the total generating capacity of the U.S. today. Here is the breakdown of electrical generating capacity in the U.S as of 2005:
Natural Gas 18%
I should mention that nuclear power produces no greenhouse gas in generating electricity, but due to public sentiment, there will be no more nuclear generating capacity added in the U.S. . It also has its own environmental issues that have yet to be solved such as long term storage of the radioactive waste it produces. It’s also not ‘renewable’ since the fuel sources are finite.
Around 70% of electricity produced in the U.S. is from CO2-emitting processes. Energy conversion is more efficient in power plants than in cars, as high as 60%, compared with 30% or less for internal combustion engines, but there are transmission losses so that by the time the energy gets to the end customer, another 7% is lost. And of course, there is the cost of the generating and transmission infrastructure that has to be added to the cost of electricity as well as battery charging inefficiencies. Still, even when you account for these inefficiencies, electric cars can come out ahead of the efficiency equation, offering approximately 43% conversion efficiency on fossil fuel vs. 30% you get from conventional cars. They also can take advantage of some other relatively minor efficiencies (~5%) such as regenerative braking and wasting no energy idling while waiting at stop lights, provided you’re not running the air conditioning or heater.
But remember earlier when I mentioned that the energy density of batteries is less than 1% of fossil fuels? The energy it takes to move a car around is very much dependent on its weight. The General Motors EV-1, which is the subject of much of the film, weighed only about 1600 lbs without its batteries which in itself is an achievement. It had an additional 1200 lbs of batteries which gave it a curb weight of around 2800 lbs. On a 2800 lb car, 15 gallons of gas comprises only a small percentage (~3%) of its weight and would be enough to propel it for at least 450 miles assuming a very conservative 30 mpg fuel economy. But in an electric car, the equivalent energy storage, even taking into account the efficiency of the electric propulsion system, would require you to carry more than 6000 lbs of batteries. Imagine what
that would do to the fuel economy. In the case of the EV1, to compensate for this disparity in energy density, they cut the range by more than 80% to around 75 miles, and carried only 1200 lbs of batteries instead which was still a hefty 40% of its curb weight. The EV-1 held around 80 MJ of energy in its batteries. This is the equivalent energy provided by roughly a half gallon of gasoline. A recharge, which took up to 5 hours, required approximately $2 worth of electricity.
In experiments with the EV-1, it got between 60 and 80 mpg when retrofitted with internal combustion engines, which is to be expected for a car with many energy saving refinements such as an extremely low drag coefficient, weight saving materials like an aluminum frame, and low rolling resistance tires. However, the one feature that saved it most of its weight was the decision to make it a two-seater. An equivalent 4-seat model would have been limited to only half the range of a two-seater.
The battery technology in the EV-1 changed several times, going from lead-acid to NiMH. This had the effect of increasing the energy density from about .5% to .8% the equivalent of gasoline. It should come as no surprise that rechargable batteries have limited a useful life. About once every 3 to 4 years I have to replace my car, motorcycle, and airplane starter batteries and I would expect that to be the same on an electric car. The EV1 suggested a full replacement every 25,000 to 35,000 miles. All rechargeable batteries such as lead-acid, Nicad, Li-ion, and NiMH have a limited life span both in time and in the number of charge/discharge cycles although it can be shortened by abuse and some cells will no doubt fail prematurely. The capacity of the batteries also declines over their useful lives. The EV1 held 26 batteries and imagine the sticker shock you’d get when they all needed to be replaced. Even if they could be purchased for the same price as an equivalent starter battery, say around $100 each, you’d be faced with a bill of $2600 every two or three years, say nothing of what 1200 lbs of batteries per vehicle every few years would do to landfills. In fact, battery life and battery replacement was never mentioned in the movie. It’s somewhat ironic that the batteries were the only cause that was given a ‘not guilty’ verdict by the movie when, in fact, battery technology has more culpability than any single cause in the killing of the electric car. If it were possible to store electrical energy with the same density as gasoline, the electric car may well have replaced the internal combustion cars a long time ago.
The killing of the electric car was not the result of some well orchestrated conspiracy by nefarious forces. It is a simple case of trying to push something on consumers by appeasing do-gooders who have a very superficial understanding of technology and the environmental problems they are trying to solve.
I think GM should have received more respect by the film makers for their efforts instead of being dragged through the mud after having spent more than a billion dollars trying to push the limits of technology that just wasn’t ready for mass adoption.
When the technology is ready, electric car will appear, but for now, no amount of whining and assigning blame will change what happened to the EV1.
3 responses to “Who Really Killed the Electric Car?”
Mike Travaline August 16th, 2008 at 02:07
The entire commentary is subject to debate; as an engineer I would have though that efficiency would be the crux of your judgment. Most commutes consist of a sold occupant in the greater number of vehicles the very idea of using a large vehicle for this purpose defeats the concept of efficiency. One would not use one’s RV or motor home for their daily commutes so why not a single or two seat commuter vehicle and reserve the use of a larger vehicle either owned or rented to be used on an as needed basis. The automotive industry promotes luxury, power & speed more so than basic transport functionality in car/van/truck designs. Two things being overlooked in your observation 1st and foremost your viewpoint is not substantiated by fact; at one time electric vehicles out-numbered combustion engine vehicles in urban settings. EV enthusiasts are not advocating replacing all combustion engines with electric; rather they are promoting using electric for urban transportation in densely populated areas where neither distance or excessive speed are required. Mike Travaline, Tronto, Ontario
Thanks for your comment. You make some good points. I am not against electric vehicles, I just think that the movie unfairly arrived at the conclusion that the failure of the electric car was for the wrong reasons. If you’ve seen the movie, it ends with a section called the ‘verdict’ where it passes out judgment on what it feels like are all the ‘guilty parties’. I found that to be at odds with my conclusions, so I reversed the verdict and blamed the batteries, the only party that was declared ‘not guilty’ in the movie.
If batteries had energy density that was on par with gasoline (i.e., 47 MJ/kg.) we’d likely have quite a few electric vehicles on the road. But even the best batteries (Li-ion) have only about .7 MJ/kg and they are quite costly.
I’d love to have an electric car for my local commuting activities and some day I hope I will. Today I have an SUV and a motorcycle. I use the SUV when the weather is bad or when I need to carry something big. I use the motorcycle whenever I can, including some lengthy trips.
I wrote up another blog entry about the topic of having a small commuter vehicle here.
It would be great to have one vehicle that did everything and had great fuel economy. Someday in the future perhaps we will. But I doubt it will use current battery technology.
Just the other day I was listening to Leo Laporte’s podcast and he was asking one of his guests (Jason Calacanis) when he’d drive his new Tesla roadster up to show it off. They live about 400 miles apart. The answer: never. It would take 3 days to complete the trip whereas you could do it in less than 8 hours with a conventional vehicle.
So it appears that if you want to have an electric vehicle, you need to have it as a 2nd or 3rd vehicle. That means you need a bigger garage and have to pay more of the costs associated with owning vehicles, which can be higher than the cost of operating a single conventially-powered vehicle, even if it doesn’t get great fuel economy.
[…] scooter’s 462 lb weight. That’s a nearly identical battery-to-vehicle weight ratio of the GM EV1 that I wrote about previously. With an MSRP of nearly $12K, this scooter costs about twice what an equivalent gas powered scooter […]
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