" We can expect 48% of the energy from renewable electricity to be lost in conversion to liquid fuels, using the average value for drop-in diesel technologies from our previous economic modeling work. To compound the problem, according to various studies 70% of the energy in those fuels will be lost when they are combusted in internal combustion engines, for a total efficiency of 16% for the e-fuels pathway. Therefore, the vast majority of the energy from the sun or wind is lost. In contrast, the majority of energy used by electric vehicles actually goes to powering the wheels, losing only 10% in charging and 20% by the motor and for a total efficiency of 72%."
There is lots of (paywalled) proper economic analysis of current methods of Electrofuel generation from atmospheric carbon, the summary is that the current processes cost multiple times more than similar fossil fuels, with the main cost factor being the cost of electrolyzed hydrogen per kg, and captured atmospheric carbon cost per kg, and all of that comes down to the cost of the energy consumed during the process.
Edit: other than any research, the main indicator (for me) is that nobody hasn't yet offered renewables based liquid hydrogen or atmospheric carbon Electrofuel at nearly viable prices for today's world. If the technology was energy efficient, these fuels would be flooding the market already even at 2x the price, but the cost of producing these is currently 5x or higher. That's why the first target for such fuels is commercial aviation and sea transportation where the cost of fuel can be absorbed less painfully.
52% efficiency sounds fantastic; the other 70% loss is equally present when you're burning fossil fuels in the same engines. of course it is very relevant to the electric vehicle comparison, but not to replacing fossil fuels in peaker plants or airplanes, which is the topic at hand
and it's fantastic news that the main cost factor is the cost of the energy input, rather than, for example, defouling or catalyst replacement. because once the electric grid is mostly renewable and intermittent, so that energy is free in the daytime, synthetic fuels will be immensely cheaper than they are now. perhaps by even more than 5x :)
initially the carbon dioxide won't come from atmospheric capture; carbon capture at the source is immensely cheaper. perhaps as the number of fossil-fuel and biomass point sources dwindles, atmospheric carbon capture will become competitive, but i suspect that it may
16% cycle efficiency might rule out liquid synfuels for grid-scale energy storage, but hydrogen should be closer to 50% (60% combined-cycle turbine times 80% electrolysis), or perhaps higher with fuel cells, and though that's much lower than batteries, it's still a viable alternative to nuclear if batteries don't work out due to shortages or whatever
https://theicct.org/e-fuels-wont-save-the-internal-combustio...
There is lots of (paywalled) proper economic analysis of current methods of Electrofuel generation from atmospheric carbon, the summary is that the current processes cost multiple times more than similar fossil fuels, with the main cost factor being the cost of electrolyzed hydrogen per kg, and captured atmospheric carbon cost per kg, and all of that comes down to the cost of the energy consumed during the process.
https://www.carboncommentary.com/blog/2021/11/18/how-much-wi...
Edit: other than any research, the main indicator (for me) is that nobody hasn't yet offered renewables based liquid hydrogen or atmospheric carbon Electrofuel at nearly viable prices for today's world. If the technology was energy efficient, these fuels would be flooding the market already even at 2x the price, but the cost of producing these is currently 5x or higher. That's why the first target for such fuels is commercial aviation and sea transportation where the cost of fuel can be absorbed less painfully.