The only reason you can't run your car entirely on hydrogen gas is the compression ratio is not designed for the higher combustibility, specifically the pistons need not depress as far as they would for gasoline/diesel. Oil production and logistics is carefully controlled and as such easily rigged.
Now we have hydrogen fuel cells which are simply nothing more than lightly electrically charged metal plates where hydrogen gas contacts fresh air, and the hydrogen gas combines with the oxygen in the air along the charged metal plates so that hydrogen and oxygen molecularly fuse together and produce a very strong electrical discharge where h2o goes out the exhaust, just as it would if you burnt hydrogen in a combustion engine as well.
Seeing as how Simcountry takes place in the future, it makes no sense that there is a power industry at all because in reality hydrogen can be created through an embarrassingly simple process called electrolysis of water where for instance a very small electric current (splits h2o molecule), perhaps from a solar panel for instance, can create a large volume of hydrogen gas to be used as fuel in a hydrogen fuel cell or even a combustion engine.
The reason we use oil in the "21st century" is because it is what gives the USD value. This is also known as the 'petrodollar.' OPEC only takes USD for oil, and if you want to trade oil in any other currency than the USA will 'liberate' your country. Of course selling cars/power generators that run on fuels not produced by OPEC is out of the question.
Water is basically a powerful unrefined fuel. . . .it can be refined with nothing more than a solar panel, where it can be recombined back into water and the electrical discharge captured into capacitors or batteries or directrly into electrical motor, or used in a boiler to heat steam turbines for alternators. . .
Hydrogen gas has often been said by propagandists to be too unrealistic to refine, but they would never dare compare it to the refining of gasoline and diesel. It has also been said to be too dangerous to transport, yet there is no need to transport it other than from a building (or pump) to your vehicle, where only a small amount of hydrogen (a tank or so) is required to propel the vehicle. Gas tanks can be hardened to easily withstand kinetic collisions and gunfire. It would be interesting to see a vehicle where h2o is captured from a condensator and exhaust h2o rerouted into an electrolyser and back into a fuel cell!
The entire power industry is a pathetic scam, but while on the subject it may be worth noting that the majority of power plants use the burning of natural gas rather than oil to heat steam turbines.
As I said Simcountry is supposedly in the future and therefore I do not understand why there is a power industry at all. If you want infinite power, get a well and a solar panel. You can use a small copper wire, i.e. a clothes hanger, to produce infinite hydrogen fuel which can be refused into h2o through electrically charged plates or burnt in a combustion motor to propel a vehicle or burnt to heat a steam engine+alternator in a power plant. This is very simple stuff that has been around for more than a century.
Hydrogen is not the only answer though. Nikola Tesla put a coiled copper rod in the ground and it produced a ton of energy. I won't even bother getting into that or I'll be labeled a 'conspiracy theorist.'. .
Just know that you pay for electricity because you are being robbed. There are many businessmen out there who literally do not want the people to have the power or they would be out of business.
The reason you may have not heard of this is the same reason you may have not heard of fractional reserve lending pyramid scheme, the world not being a ball spinning in 4 different directions, the designed failures of bolshevik communism, endless wars of the petrodollar and maintaining currency exchange rates, and many other things you probably should have heard of. . .
by the way, you mention "carbon footprint.". .are you aware that co2 (carbon dioxide) is plant food? The more co2 produced, the more co2 is absorbed by vegetation, and the more vegetation spreads across the world. . .burning of oil = more plants! Have you ever seen plants growing alongside a heavily trafficked road? I bet you have!
That is all I have to say on the subject of 'clean power.'
If you ask me, the needless power industry in Simcountry is an interesting aspect to the game that is Simcountry and I have no issue with it, being in a mere game that is. If you want change I would much rather see the ability to create multiple units!