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Originally Posted by Alex
I mostly agree with Frugal.
But when we are talking about physics, the needs become less malleable, and conclusions can be drawn. Those who ignore the inconvenient facts aren't more open-minded, they are just, well, wrong skipping over some important data. Batteries, even our most advanced, have a small fraction of the energy by weight compared to gas (or diesel, or CNG, etc.). If you want to have the same amount of energy in batteries that you have in fuel, you need to carry many, many times the weight, at many, many times the cost.
Gasoline has 33.41 kwh/gal ( link). 3 gallons of it will run you less than $9, and it will weigh about 20 pounds. You will have more energy than the latest $100K+ P90D Tesla (that 90 stands for the 90 kwh battery pack). That battery pack costs $20K-$30K, and weighs 1200 pounds.
Those who believe that somehow those stark differences will get close to each other at a rapid pace are discounting both math and science. Now, they may be counting on external forces (political, scarcity, etc.) to more quickly tip the playing field, and that very well might turn out to be the case. But when compared to batteries, let alone just about any other source of stored energy, gas *is* better at energy per volume, per weight, and per cost. And will be for our lifetimes.
To the Wolf's point though, figuring out how to convert that gas into propulsion has some pretty good options at the moment. It may turn out that a hybrid is the best way to go (most efficient, most cost-effective) for quite some time, compared to a pure battery electric vehicle. Advantages of large range and cheap available energy in the onboard fuel, electric motors used to complement the efficiency of the gas engine. At some point that might transition over to pure BEV, but not in our lifetimes (or our grandkids lifetimes). And at that crossover point, it's unlikely to be due to batteries of today incrementally improving. It will either be some as yet unforeseen advance, or the cost of oil and/or synthetic hydrocarbon fuel getting so high as to make their physical property advantages no longer cost-effective. |
The physics you mentioned are valid, but incomplete. You didn't consider that the pinnacle of technology for converting chemical energy of gasoline to motion is, at the very exotic best, barely over 30%. That means over 60% of the potential energy in gasoline is converted to just exhaust, radiator, and brake heat. It performs no useful function, and the brake heat cannot be recaptured for later use. That wasted energy is one of the most inconvenient facts about internal combustion, and there's no foreseeable way around it because that's the nature of the physics of internal combustion. IC engines are just terrible at efficiency, and always will be.
In our lifetimes we've seen lithium battery technology completely outpace lead-acid. Remember, lithium wasn't really explored from a pure R&D point of view until the 1970's, and wasn't commercially viable until the early 1990's. It is now a fairly stable technology that exceeds lead-acid in about every way except price, and that's is falling on a daily basis.
More importantly, our understanding of chemistry has increased exponentially and future battery technologies will perforce be developed faster. I see no reason why it can't roughly follow Moore's law in concept, but with somewhat slower timeframe.
Gasoline was a great way to store energy in the old days when there wasn't anything better, but that was then, and today there are much more efficient technologies out there. Within the next 20-40 years I see wholesale adoption of EV technology because of the efficiency, the ability to source electrons from anywhere including non-carbon sources, and because of the long-term reliability and durability that EV offers. Hybrids are a definite link in that transition, and will get people weened off of chemical fuels.
When (not if) gas hits $10 in today's dollars, a lot of folks invested in that 100 year old stagnant technology are going to be left red-faced and empty-handed.