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Are We Reaching the Electric Car Tipping Point?
HughPickens.com writes: Geoff Ralston has an interesting essay explaining why it is likely that electric car penetration in the U.S. will take off at an exponential rate over the next 5-10 years rendering laughable the paltry predictions of future electric car sales being made today. Present projections assume that electric car sales will slowly increase as the technology gets marginally better, and as more and more customers choose to forsake a better product (the gasoline car) for a worse, yet "greener" version. According to Ralston this view of the future is, simply, wrong. — electric cars will take over our roads because consumers will demand them. "Electric cars will be better than any alternative, including the loud, inconvenient, gas-powered jalopy," says Ralston. "The Tesla Model S has demonstrated that a well made, well designed electric car is far superior to anything else on the road. This has changed everything."
The Tesla Model S has sold so well because, compared to old-fashioned gasoline cars it is more fun to drive, quieter, always "full" every morning, more roomy, and it continuously gets better with automatic updates and software improvements. According to Ralston the tipping point will come when gas stations, not a massively profitable business, start to go out of business as many more electric cars are sold, making gasoline powered vehicles even more inconvenient. When that happens even more gasoline car owners will be convinced to switch. Rapidly a tipping point will be reached, at which point finding a convenient gas station will be nearly impossible and owning a gasoline powered car will positively suck. "Elon Musk has ushered in the age of the electric car, and whether or not it, too, was inevitable, it has certainly begun," concludes Ralston. "The future of automotive transportation is an electric one and you can expect that future to be here soon."
The Tesla Model S has sold so well because, compared to old-fashioned gasoline cars it is more fun to drive, quieter, always "full" every morning, more roomy, and it continuously gets better with automatic updates and software improvements. According to Ralston the tipping point will come when gas stations, not a massively profitable business, start to go out of business as many more electric cars are sold, making gasoline powered vehicles even more inconvenient. When that happens even more gasoline car owners will be convinced to switch. Rapidly a tipping point will be reached, at which point finding a convenient gas station will be nearly impossible and owning a gasoline powered car will positively suck. "Elon Musk has ushered in the age of the electric car, and whether or not it, too, was inevitable, it has certainly begun," concludes Ralston. "The future of automotive transportation is an electric one and you can expect that future to be here soon."
I'll be sure to carry a supply of D cell batteries I can toss to any electric car owner I see on the side of the road, completely out of juice.
Say, how much electricity can you carry in a 2 gallon container?
When Fascism comes to America, it will call itself Anti-Fascism, and tell you to give up your guns.
Can the electric grid handle charging that many cars every night? Not to mention that there can exist a better way, in terms of overall efficiency. If someone has better numbers than the ones I present here, let's see them! .5*.95*.95*.95= about 43% overall efficiency, and regenerative braking increases that number.
It is known that hydrocarbon powered cars typically turn chemical energy into mechanical motion at about 35% efficiency (45% for Diesels). It is known that large power plants generate electricity from fuel at about 50% efficiency. The process of charging a battery is about 75% efficient, turning electrical energy into chemical energy. The reverse is also true, for battery discharge (75%), and the electric motors of an electric car are about 95% efficient. We multiply these numbers to get the overall efficiency of conversion of original fuel energy into mechanical motion for the car: about 27%. Even allowing for regenerative braking energy-recovery, it looks like ordinary cars win the efficiency thing here. We need better than that!
Consider replacing the electric commuter-car battery with a flywheel. We have the tech to do this for ranges of 50 miles or so. Since the flywheel is a motor-generator, it operates at about 95% efficiency, storing and producing energy. The car still has a separate electric drive motor, also 95%. The numbers are multiplied as before:
There is another factor to consider. To cruise the road at highway speed, a car only needs about 15 horsepower to fight wind resistance. All the rest of the horsepower in a car is needed for related to fast acceleration. A flywheel system can easily provide the power for fast acceleration; it could be accompanied by a small engine that generates 15-20 HP for cruising, and charging the flywheel (plus add regenerative braking). Also, a fuel tank gives the car lots of range (the flywheel doesn't have to be so big, to store energy for even a 5-mile range). Total system weight could be significantly less than today's hydrocarbon engines, and total system energy efficiency will probably be around 40% (an engine designed to run at a particular constant speed, for generating say 20 HP, is more efficient than one that revs at different rates).
And here is one more major factor: chemical reactions usually involve two things that we can call here "fuel" and "oxidizer". This is as true for a battery as it is true for a gasoline engine. The difference is that in the battery, both the fuel and the oxidizer are permanently stored; the total weight of chemicals always has to be carried around. The fuel-burning engine is associated with only carrying the fuel around; the reaction products (mostly CO2 and H2O) are dumped and their weight is never carried around. Now you know why electric-car batteries weigh so much!
We should be thinking about replacing batteries with "fuel cells", because, like hydrocarbon engines, only fuel (most agree hydrogen is best) needs to be carried around, and the waste (H2O) can be dumped. Methods of generating hydrogen are improving --can do it straight from sunlight; no need burn hydrocarbon fuel in a large power plant! That changes the efficiency situation drastically! The hydrogen fuel becomes almost free after the infrastructure is paid for (must be maintained, though); the energy efficiency of generating the hydrogen can be ignored. So we have maybe 75% efficiency for running a hydrogen fuel cell to produce 20 HP, plus three sets of 95% efficiency for the flywheel and the car's electric drive motor(s): about 64% total efficiency, increased a by by regenerative braking.