There is a two or three panel sequence about alternative fuels in the comic, though.
It's in the fourth chapter, where Dr. Manhattan's history is told. And, in flashback, one of the Detroit automakers is talking to Dr. Manhattan about all the great things that cars can do, and Dr. Manhattan says, "Yes, enjoy your retirement." He's seen the future, and the future is lithium battery-powered cars. Cars that happen because of Dr. Manhattan.
He's not inventing anything. That's part of the world of Watchmen. The world of 1985 is powered on alternative fuels.
You know, I'm all in favor of electrically-driven cars as opposed to combustion-driven cars. I've worked a little bit on that sort of thing. (And add into the mix "fuel-cell" based cars, which use a chemical reaction not to create mechanical motion inside the engine but rather an electrical current which can power electrical devices... sort of a "half-way" point.)
Unfortunately, today, I keep hearing technological illiterates talking about "batteries" as though they CREATE POWER. Which is entirely untrue.
First thing... "battery" isn't a description of a power storage device. It's a description of a CLUSTER of power storage devices. In other words, your typical "AAA" isn't a BATTERY, it's a CELL. The only actual "battery" you'd normally use is the 9-volt, which is basically a box containing 6 1.5v cells in series. It's a battery because it contains multiple cells. Your car has a battery... because it contains multiple cells. Most of those little cylindrical things we buy are NOT "batteries" at all. I mention this mainly to ensure that we use the right words for the right purposes.
It's true that you can manufacture a one-time-use cell which has an inherent electrochemical potential without being "charged." Your typical Duracell (non-rechargeable) cell is that way. Of course, once that's discharged, it's useless and can only be discarded... not something useful for the purposes of powering an automobile, don't you agree?
The lithium ion based cells that are most commonly used in "electric vehicles" today are, however, rechargeable. The rechargeables you'll buy at Best Buy are normally nickel-metal-hydride, which has largely superseded nickel-cadmium rechargeables over the past decade.
With a decent-size cluster (or "battery") of lithium-ion cells, you can get enough electochemical potential to drive an automobile in a reasonable fashion. It's true.
But what people keep missing is that it takes power to CHARGE those batteries in the first place.
SO... it gets generated in a power plant, sent over long lengths of wire, multiple junctions and interfaces, and is then transferred into the battery (as a chemical change), then needs to be discharged from that battery to drive the electromagnetic devices it powers. Each and every step of that process has losses... so while the device ITSELF may seem reasonably efficient, you need to track the efficiency of the power output from the original source of power, not simply from the battery itself, to make a reasonable comparison.
When you look at things that way, electrical cars are no more efficient (in terms of total power required to provide equivalent propulsion) than are internal combustion drive cars. In fact, depending on how far you are away from the power generation facility and on the quality of the transmission lines, you can be a lot LESS efficient.
What needs to be addressed here, then, is not "how good are the batteries in the cars" but rather "what is the ORIGINAL SOURCE OF POWER?"
If we continue to generate power using coal-fired or oil-fired power plants, you'll ultimately end up with greater fuel consumption to move a car the same distance. It just gets consumed at a different location... in a plant rather than in your car.
The argument that "wind power" or "wave power" or "solar power" can replace that form of power generation is spurious. I'm all for using those however and whenever we can (including the building of the offshore windfarm that Senator Kennedy nixed because it would have spoiled his view from his yacht... and no, I'm not kidding about that, it's true!). But the total power output from those types of sources can only provide a fraction of what we currently need, much less what we'll need for the future. CERTAINLY not enough to make electrically-driven cars a wide-scale practicality.
So combustion-driven power plants driving battery-charge-driven cars are WORSE, environmentally and consumption-wise, than the equivalent (gasoline-powered cars). And "alternative sources" can't replace combustion-driven power sources.
The general idea behind lithium-ion battery technology isn't anything new or revolutionary, though we've improved the processes used to make these recently. In other words, in this FICTIONAL WORLD, there's nothing Dr. Manhattan could have contributed to make the batteries a practicality.
No... what he had to have given that other world would have to be an alternative power source. Something that creates no combustion products.
Hmmm... we already have something like that. And most of the world (the US excluded) uses it extensively. I'm talking about nuclear fission.
So, maybe what Dr. Manhattan provided was a way to optimize fission to be more easily controllable and to "clean" the waste in some fashion (perhaps even "cleaning it up" himself???)
On the other hand, the "holy grail" of power generation, so far, would be controllable FUSION. Despite claims from time to time, so far nobody has ever created a controllable fusion reaction, much less a "cold fusion" reaction.
The nice thing about fusion is that it generates a lot more power per unit of consumed fuel... that the fuel itself is plentiful (simply monatomic hydrogen ions, easily created). We simply lack the ability to control the reaction... the only way we can initiate it right now is through the detonation of a fusion bomb, and there's no way we know to prevent a chain-reaction.
SO... what Dr. Manhattan would have given the "Watchmen" world would either be a way to use fission more cleanly, or a way to safely initiate and control fusion. Both of which seem perfectly reasonable for someone with his powers.
I just wanted to point this out, because of the misconception that it was somehow the BATTERIES which made the electrical cars a reality (and which could, by extension, make them a practicality in OUR world!) That's simply not the case.
Electrical cars in widespread use in any world... real or "realistic fictional"... require extremely widespread use of nuclear power to be practical.
Which is exactly what a fictional "Dr. Manhattan" would lead towards... so it fits quite well in this situation, I think.
How the hell are they squeezing all of this into one movie? In any adaptation from book to film, I expect a good amount of story condensation, plenty of omitted details.
