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by masta 2425 days ago
The efficiency of the whole chain is pretty abysmal. Capturing free-air CO2 in large quantities is expensive, you better just store that in the ground and keep it there. I would not expect an efficiency above 20-30% for the synth-fuel generation, and then you put it into ICEs which also just have a 15-30% efficiency. You're burning 90% of the original energy, instead of using it to charge EVs with an 80-90% panel-2-wheel efficiency.

Power-2-X is still important as a long-term storage technology, but it's better to synthesise Methan which can can be generated with a better efficiency and can also be burned cleaner and with 55-65% efficiency in modern gas turbine power plants. This also allows for capturing CO2 at the power plant and create a complete cycle.

Synth-fuels will be a niche, used for long-haul trucking, heavy machinery and airplanes, but even there Hydrogen is going to be the better option at some point.

1 comments

Energy efficiency doesn't matter, there is enough sun available in remote areas. The problem is energy storage. Storing electricity is really expensive, and cumbersome. It can not be easily transported without a vast expensive infrastructure effort especially concerning remote areas.

We have loads of fluctuating energy generation from renewable sources and hugely fluctuating energy consumption. This means we need loads of storage. Nobody ever talks about the storage.

Also staying 20 min at a charger just to fill up my battery is absolutely impractical. Fast charging is already at its technical limits. Compare that with the 45 seconds I need to fill my gas tank and have enough energy to drive thousands of miles.

You use your car for how many hours a day 4-6 hours max. The rest of the time it is parked at work or home just put it on the charger when it is parked. We are used to ice cars so think about filling up once the tank is almost empty and can't get fuel everywhere it is not so with electric cars. You should not be visiting a charger unless going on a long trip so in actual fact 5 min spent at the gas station filling up is more time than you will spend filling up an electric car.
Efficiency is everything. Transporting fuels is even more cumbersome than transporting electricity. At only 10% or even 20% efficiency, you'll have a tough time to recoup the energy it took to built the plant creating the synthetic fuels .... Sorry, but Math and Physics is not on your side.

Millions of EVs integrated in the grid will serve as an amazing type of Energy Storage. We'll have to go to a decentralised energy grid, utilising demand management to a maximum.