If you had all of that H2, what is the additional cost to just fix some CO2 into hydrocarbons?

It feels like that would be a much simpler way to get to net zero than having to reinvent all of the infrastructure.

So much simpler that I wonder why anyone would keep trying on hydrogen. Which makes me darkly suspect that the goal is to take our attention off the solution that's already being deployed, i.e. wind and solar.

Regardless of net efficiency, that still entails collecting CO2 at a central facility (where it could have been dealt with in other ways, such as injection underground) and sprinkling it through the air as you fly over delicate ecosystems. I'm sure bankers see both as net zero, but condors might have more issues with your simpler workaround.

> sprinkling it through the air as you fly over delicate ecosystems

I wouldn’t be so sure spraying water vapour is innocuous. As long as it’s atmospheric CO2, the environmental impact of synthetic fuels is much less than rebuilding the world’s air fleet and fuelling infrastructure to accommodate hydrogen.

It takes a lot of energy to pull CO2 from the air since it is only 400ppm. It also takes energy to make hydrocarbons. This means they will be really expensive. They might be used for classic cars but can’t replace fossil fuels.

Hydrogen or ammonia have advantages that can be made from water and nitrogen. Ammonia may be good for ships and planes since can be liquid at cold temps. But can’t substitute in cars.