In Defense of the Electric Car
Since I spent yesterday waxing ecstatic about today's gasoline-powered, internal-combustion-engined cars, I'm going to spend today doing the same with what I think is tomorrow's car--the electric car. Though I should probably start off by clarifying that by "tomorrow" I mean, oh, probably 10-30 years from now.
I'm titling this "In Defense of the Electric Car" not just because it creates a nice parallel with my previous post, but because I really think the concept of an electric car needs defending. Just as today's cars have their share of detractors, so do hybrids and full electric cars. Within the automotive enthusiast community, hybrids and full electric cars seem to have become political and social symbols with pretty significant baggage. While I get that, I think it's a shame--it's not hard to imagine an extremely cool electric car.
Before I start, please realize that I'm not a mechanical or electrical engineer. Nor am I particularly well-informed. I'm just a wild-eyed car enthusiast who loves technology and is armed with excitement and, probably, a lot of bad information. Please feel free to correct my ignorance and flights of fancy in the comments.
Imagine a regular car, but strip out everything needed to generate power and and transfer it to the drive wheels--no engine, no large clutch or transmission assembly, no drive axle, no CV joints, no drivetrain at all. Throw away the current drivetrain, and with it the weight, moving parts, and friction losses inherent in today's drivetrains.
Then imagine a new powertrain--not one large front-mounted engine, causing packaging and styling issues and disturbing the car's weight distribution--but at each wheel a powerful electric motor and a gear reduction (essentially a one-speed transmission that doesn't require a gearchange). Each electric motor is light, highly efficient, highly torquey, extremely responsive to the vehicle's on-board computer, and capable of independent power generation. Why four motors and not one? Well, sending electricity to each wheel requires much less bulk, weight, potential for failure, and loss of efficiency than sending power to each wheel in a traditional all-wheel-drive vehicle.
This design does a few things. To begin with, it cuts weight, bulk, and mechanical complexity, allowing designers to make cars that are lighter, leaner, more aerodynamic, and more spacious inside. As an example, take a look at the innovative Skateboard chassis pictured here--GM unveiled it as a concept in 2005. There are a lot of detail differences here from what I'm talking about--GM has a large electric motor mounted up front, for example--but this should illustrate the amazing packaging potential of a chassis that is largely devoid of today's drivetrain hardware.
Even more exciting from my standpoint are the performance benefits of such a design. As we discussed on Wednesday, electric motors are highly efficient--75-95-percent efficient versus today's engines, which are 25-percent efficient. Electric motors are also very torquey, meaning they have fantastically immediate power response. That combination of torque and a lighter chassis is appealing, but what really excites me is the flexibility of having a motor at each wheel. With the availability of immediate and independent torque at each wheel, there's the potential for lighter, more flexible, more integrated, and more efficient versions of today's traction control, stability control, and all-wheel-drive systems. Each wheel could provide exactly the right amount of power for optimal acceleration and handling; electric motors can react so quickly that the power mix at each wheel could help determine handling trim and eliminate (or, optionally) encourage oversteer.
Not to sound like a misty-eyed enthusiast, but I'm really excited about the capabilities of such a car. I can easily imagine blasting through some twisties in light, compact sports car, electric motors whining, the torque blasting me out of each corner, each wheel generating and constantly adjusting the appropriate level of power to maintain traction and power the car away from the apex. Traditionalists might argue that while this car would be extremely fast and capable, it would be less fun than hustling a nervous 1960s Porsche 911 along the same road; it might be slower, but trying to keep it from flying off the road backwards in each corner might be more engrossing. This might be true, but that hasn't stopped us from enjoying continually more capable cars--and it's just more reason to have a capable new car and a 1960s Porsche 911 in the garage.
And now, after having built up this beautiful vision, it's time to ruin it all with a dose of reality. Left unsaid in my flight of fancy above is the fundamental killer of any electric-car fantasy--the problem of supplying electricity to those electric motors in the first place.
On Wednesday we talked about how a $3 gallon of gasoline, easily available in nearly every neighborhood in the United States, generates enough power to drive a 2,500-pound Honda Fit 40 miles. A tank of 10 gallons of gasoline, which takes about five minutes to pump, can propel that 2,500-pound car 400 miles--or the distance from Los Angeles to San Francisco. No electric car can rival this seemingly commonplace achievement.
Today's most advanced quasi-production electric car, the Tesla Roadster, offers by far the best range we've ever seen from an electric car, at around 250 miles per charge, but that doesn't mean that it can match the Fit for usable range. For one thing, the 250 miles per charge is a theoretical range--some hypermiling devotees have nursed the Tesla more than 300 miles, but the Wall Street Journal didn't see anything close to 250 miles. Instead of a five-minute fill-up, the Tesla needs lots of time to recharge--several hours for a custom, 240-volt, 70-amp line, which is not exactly a common outlet. Charging on a normal 120-volt plug would take a day and a half. Oh, and one other small issue--the Tesla, thanks partially to the highly sophisticated lithium-ion batteries (like you'd find in a laptop), costs an eye-watering $110,000. The Tesla would cost less with more commonplace batteries, but it would weigh substantially more and its range would plummet.
So, why the disparity between gasoline- and electric-powered vehicles? Well, gasoline is a compact and inexpensive way to buy lots of power, and it's easy to store that gasoline in the car. By comparison--I'm about to get technical here, so try to keep up--batteries suck. Batteries tend to be very heavy, toxic to make and dispose of, and they don't hold nearly enough power to push a normal car as far as a tank of gasoline. You can ameliorate--not eliminate--some of those symptoms by using highly sophisticated batteries like the Tesla does, but the trade-off is a high degree of expense. Just look at the Toyota Prius' battery pack--it's a small battery that weighs only about 60 pounds, and it isn't asked to serve as the car's primary motive source. Despite the more modest demands, replacing the Prius' battery pack still costs $3,000-$5,000 (the lower figure is to purchase the pack; the higher figure is purchase and installation).
You also have to treat batteries very carefully--you can't deplete them too far or leave them depleted for too long without damaging their ability to hold a charge. They don't like conditions that are too hot or too cold, they lose efficiency over time, and some types of batteries need to fully discharged and recharged from time to time. Also, unlike a car with a quarter-tank of gas, an electric car with 25-percent charge will not perform as well as it does at full power.
None of this should come as a surprise; speaking personally, I have owned radio-controlled cars that go through batteries in bulk; a trunk-stored, battery-powered, emergency jump-starter that is now a useless brick because I didn't religiously keep it charged; an iPhone that exhausts its battery in four hours if I dare to use its full capabilities; and a two-year-old laptop in which the expensive lithium-ion battery eventually couldn't hold more than a 20-minute charge.
Of the three major battery attributes--light weight, high energy storage, and low price--any given modern battery can give you two, maybe one. And while it's tempting to say that the thing standing between me and my fantasy electric car is better battery technology, that's the same barrier that has held back electric cars since the car itself debuted at the beginning of the last century. Reasonable automotive batteries are just not capable today of storing as much energy as is contained in a full gas tank; and one of this has even addressed the fact that electric cars aren't truly emissions-free. The cars themselves don't emit, but the power plants that generate the electricity usually do.
I admit the last seven paragraphs have turned this post into a pretty awful defense of the electric car, but here's the thing--I'm still a believer. My reasons include infrastructure, power generation flexibility, and the possibility of on-board power generation. Let me explain.
First, infrastructure. The other contestants for advanced powertrain supremacy include ethanol, methanol, liquid natural gas, and liquid hydrogen used in something like today's internal-combustion engine. The problem there is that those fuels provide inferior power density at a higher cost than gasoline and are much, much less accessible than gasoline. So, to sum up, you need a larger quantity of a more expensive fluid to do the same work, and it's a lot harder to get.
So besides being less efficient in terms of power generation than gasoline, these alternative fuels would require a lot of work to be realistic options for the typical driver. A world in which cars primarily run on, say, liquid hydrogen, would not only require changes in our cars, it would require changes in how we create, store, transport, and distribute that fuel. That's a big deal, and it takes a lot of money from a lot of different organizations to make happen. It's possible--it happened when we built the gasoline infrastructure in the first place--but changing what already exists can often be harder than building something from scratch. I'm enough of a cynic that I won't believe we can rapidly make that kind of fundamental change until it happens.
From an infrastructure perspective, electricity is a different story--electricity is even more widely available than gasoline. Nearly every house in America has electricity; I have as many power outlets in my garage as there are gas stations in a two-mile radius. Yes, they're regular household plugs, but even the expense and hassle of putting in a 240-volt plug pales in comparison with the time spent trying to figure out when in my commute I can make time to stop at the gas station. From an infrastructure standpoint, it would be incredibly simple and drama-free to just drive home and plug in my car just as I do my cell phone.
The electrical infrastructure isn't totally perfect--there would have to be upgrades before millions of peoplen across the country began plugging their cars into 240-volt outlets--but it's a much different challenge than would be required to move to a hydrogen-powered-car economy. Uprading a system is easier than replacing it. It would also be easier to justify and prioritize--cars would be just another in a long list of products that depend on electricity, and cars would benefit from a better, more stable electrical infrastructure just like your blender or a local machine shop's CNC machine. Cars would not require a special fuel infrastructure like they do today, and the standardization of energy needs would allow even more money, focus, and energy to be devoted to generating and transmitting electricity in a better way.
That leads into my second point--power generation flexibility. In a world in which cars run on electricity, cars would automatically benefit from improvements in power-generation technology. Today's engines are, essentially, mobile power generators--they turn fuel into energy. In the millions of cars on the road, there are just as many millions of power-generation machines, some of which aren't very well-maintained, some of which use incredibly old technology, and many of which generate power less efficiently and with more pollutants than they should.
Doesn't this seem really inefficient? Setting aside the economies of scale possible in generating a given amount of power in one plant instead of in a multitude of cars, as well as the fact that even some of today's mass-produced energy is truly emissions-free (I'm thinking primarily of hydroelectric power), today's model doesn't allow us to react very quickly to innovation. What happens as we keep getting better at generating power? Let's say automakers discovered a great way to generate power efficiently and cleanly from hydrogen tomorrow; we wouldn't realize the full benefit of that improvement until every car on the road had a highly efficient and clean hydrogen engine. We would get small incremental gains as people replaced their gasoline cars with the fantastic new hydrogen cars, but getting the full gain would take a long, long time. Every subsequent such discovery would require the same slow and inefficient changeover.
The beauty of the electric car is that it doesn't care how the electricity was generated. If we discover nuclear fusion, if we decide we're comfortable with widespread nuclear fission, if we get really good at making power from wind or solar, if we learn how to harness the fantastic energies available in space-based solar, if liquid natural gas or hydrogen emerge as highly efficient sources of power, well, great. If you upgrade the power plant, you've upgraded the electric cars. You don't have to upgrade every engine on every car to get the full benefit--and really, many potentially interesting ways of generating energy (I'm thinking of fusion, geothermal, and space-based solar as examples) don't make any sort of sense at the car scale. Making our cars electric disconnects them from all the change that has to happen as our power-generation technology changes and improves.
All of this still unfortunately leaves us with the bottleneck of today's battery technology. No matter how efficiently power is generated at the power plant, no matter how extensive the distribution infrastructure, it won't matter if the car can't do an adequate job of storing the electricity. But, while I'm not particularly impressed by today's battery technology, I don't think the case is hopless. Given time--probably at least 10 years, probably longer--battery technology just might improve enough to make a fully electric car practical. The Tesla, for example, provides high performance and reasonable range, albeit at the cost of long charging time, limited utility, and an extremely high price. Over time, battery technology might improve and minimize those issues. The Tesla is certainly flawed, but it is a glimpse of that future.
But, until we reach that point, what if we fudged a little by removing electric cars' absolute dependence on their batteries? The Tesla and other fully electric cars need to store all of their energy; once they disconnect from the electric teat, it's a one-way street to a depleted battery. But--and now I'm moving on to my final point, onboard power generation--what if we eliminated the absoluteness of that dependency? What if the car ran solely on electricity, but it minimized its dependency on its batteries with the ability to self-charge with an onboard generator? Such a car would technically be called a hybrid, but these cars are basically the opposite of today's hybrids--rather than supplementing a traditional gasoline-powered drivetrain with an electric boost, these cars would be purely electric-driven, with batteries replenished by a small onboard engine.
The upcoming Chevrolet Volt is the most well-known example of such a car. I know many enthusiasts are tired of the hype surrounding the Volt, but, bad song-and-dance routine aside, I'm genuinely excited by it. The Volt's onboard battery is primarily charged from the electrical grid as the Tesla's is, but once the battery depletes to a certain point, a small onboard gasoline engine starts up to drive the electric motor and charge the battery. Since the Volt isn't completely dependent on its batteries as the Tesla is, it doesn't need as much battery storage, cutting down on battery weight, cost, and charging time (eight hours from a normal household plug). It's not as exciting as the completely pure electric car concept I outlined above--it doesn't eliminate the traditional drivetrain in favor of a motor per wheel, and there's still an engine and fuel tank within the car--but the concept is cool.
The concept gets even cooler once you replace the traditional gas engine in this concept with a turbine. Turbines aren't entirely foreign in the car world; Anthony Cagle has already covered the fondly remembered 1963 Chrysler Turbine, and turbine-powered race cars were so successful at the Indianapolis 500 in the latter part of that decade that they were eventually banned. As Anthony said in the Chrysler Turbine post:
"Turbine engines have several advantages over internal combustion engines: They have far fewer moving parts which reduces maintenance and increases use-life; they can operate on a wide variety of fuels (including, legend has it, tequila); have much less vibration; cold-starts are not an issue; and are much more compact, light-weight, and efficient. Not to mention they produce massive amounts of torque for their size."
These are all highly applicable strengths. The major problem with the turbine in an automotive application was that it was poorly suited to put power to the ground. Internal combustion engines rev quickly and easily; we expect that kind of response when that power is directly tied to the drive wheels. But as a generator to power electric motors and to recharge batteries, a turbine would excel. The turbine wouldn't need to change speeds; it could spin at its most efficient RPM to generate power, allowing the torquey electric motors to actually accelerate the car. Turbines are roughly twice as efficient as internal-combustion engines, can run on many fuels, and they are absolutely excellent at generating electricity--virtually all electricity on the planet is generated by some form of turbine. This would make a Volt-like concept with a turbine a highly intriguing proposition.
I know next to nothing about hydrogen fuel cells, but from what little I understand they could also work in this way. The point, though, is this--for reasons I pointed out above, centralized power generation is innately more efficient than onboard power generation, but at least we have some options to supplement available batteries until batteries are truly ready for prime time.
To be clear, I don't expect any of these forms of the electric car to displace today's gasoline-powered car anytime soon. At the risk of repeating myself yet again, gasoline-powered cars are a mature, well-developed, and thoroughly tested technology, with a century of time, money, effort, and consumer testing in their favor. Fully or partially electric cars have a high bar to clear before they will represent a better overall package than gasoline-powered cars at a reasonable price. It's going to take some significant time and development before that happens.
Still, I'm excited. The whole concept just feels right, and I'm excited that we're finally beginning to experiment and start down the production path--only then will we get this figured out. Besides, I'm looking forward to feeling like a rebel in 2030 when I take my loud, smelly, and hopelessly antiquated 1986 Audi Coupe GT for a spirited drive in a world dominated by silent electric cars.
The first photo of the cutaway electric car is from www.kids.esdb.bg, the second is a commonly available press photo of the GM Skateboard chassis, the third picture is a press photo of the Tesla, the fourth is a charging image from Tesla Motors, the fifth is a battery photo that appears to be all over the blogosphere as a generic battery image, the sixth is a gas station picture from Energy Program.net but copyrighted by TheFunTimesGuide.com, the seventh is a power plant image from McCullagh.org, the eighth is of a solar power installation from Weblo.com, the ninth is a press image of a Chevy Volt, and the last image is a rare picture of the Chrysler Turbine's powerplant, courtesy of ImperialClub.com.--Chris H.