OK, let's assume you are right, for purposes of the argument. The world is certainly awash with energy, and ways of harnessing it may well be devised, and become cheap. One useful thing you could do with this cheap, plentiful energy is apply it to combining water and CO2 into hydrocarbons. Since hydrocarbons are a simple, cheap and practical way of storing large amounts of energy, even for long periods, and the energy is easy to retrieve when needed afterwards, this is a highly attractive option. Another thing you could do with the energy is store it in batteries. As I have mentioned before, battery technology has a long way to go before it is remotely competitive with hydrocarbons, in terms of storage density & efficiency, replenishment, and price, so an unattractive option. Then again, for doctrinaire political reasons governments may choose to impose massive, crippling taxes on hydrocarbons and provide massive subsidies to battery makers.
I suppose that if you could electrolyse water with all the cheap electricity, you could burn hydrogen in your motor, producing more water. But then I'm not a chemist.
It's true that another thing you could do with your (hypothetical) cheap energy is electrolyse water producing hydrogen. Unfortunately hydrogen is tricky stuff to store. It takes up a huge volume of space, unless you compress it to a high pressure (in which case you need a heavy, expensive, reinforced tank to store it in), or unless you freeze it to an extremely low temperature (which is even more expensive and complicated to do). Why give yourself the headaches which go with hydrogen, when you could just use liquid hydrocarbons?
But as Pete has said recently, and I said some time ago Energy + CO2 +H2O = Hydrocarbon + O2 which is a CO2 neutral reversible equation.
But you still have to get the energy from somewhere. Bio fuels are probably an easier option. Plant captures energy from the sun and grows cellulose and carbohydrate which are harvested and fermented to produce alcohol, but then you should know all about that. Or go down to your local supermarket, buy a gallon of vegetable oil and put it in your diesel car. There are solutions out there but they come at a price which doesn't make sense when you have cheap and plentiful hydrocarbons.
Another thing Pete is that Hydrogen is incredibly leaky, it manages to get through a lot of materials. Used to deal with Hydrogen cooled generators on the odd occasion, they were a nightmare when they started to lose Hydrogen pressure. Tracking down the leak was usually of guess work followed by trial and error.
You could make a start by using mineral-based fuel which has been stretched by adding 5% or 10% ethanol derived from plants. Actually we are already doing exactly that. Some people seem to object, but I have never seen any coherent basis for such objections.
Good point. Various experimental hydrogen-fuelled vehicles have been tried, but they must be parked in a very well ventilated garage - otherwise the inevitable escaping hydrogen becomes dangerously inflammable. Vehicles which are driven all day and every day (e.g. buses and taxis) are just about feasible to power with hydrogen; vehicles which are parked up for days weeks or months at a time - not so much.
Drilling them out of the ground is not the only feasible way to obtain hydrocarbons. They can also be fabricated by forming them out of H2O and CO2 from the air*. Burning them then just puts the same CO2 back into the air which we previously took out of it. * Assuming we have some source of energy other than fossil fuels. Which is, of course, the assumption underlying the battery-electric car concept, where we came in .
I thought Brazil did a lot of this. They burn down large bits of the Amazon to do it. That's what I've got against it. Plus arable land is required to feed the global population, if you start needing more of it to fuel cars, you'll inevitably be constricting wild and wildlife habitats, which is pretty poor.
It is not the objective of farmers to produce as much food as they are able to so that the population can be fed. Their objective is to produce as much as they can sell. No buyers = bankrupt farmers. Extra markets for their produce are welcome to farmers everywhere. Third world countries have mainly agricultural economies: richer farmers = richer countries.
