You cannot magically put electricity directly into the battery. There is a significant loss between production and powering the wheels. This is the biggest source of misunderstanding about the subject.
Of course most hydrogen vehicles are actually battery electrical vehicle where the battery is charged by the fuel cell. Reason for this is that fuel cells are not that easy to throttle up and down and typically have a lower output than the maximum input of the motor. So, you put enough battery in between the fuel cell and the motor so that you don't run out of energy when e.g. driving up a mountain. Also this enables benefiting from things like regenerative braking. Technically, you could take any hydrogen vehicle and convert it to pure battery electric by simply replacing the hydrogen bits and bops with a bigger battery. No need to change the drive train or anything else. It already is a battery electric vehicle.
So a hydrogen car or truck inherits all those supposed (in)efficiencies of battery electric and then adds the additional (in)efficiencies of the hydrogen production, storage, transport, and fuel cell conversion. The whole process starts with the same renewable energy that you would otherwise put straight into the battery. So these are additional inefficiencies that go on top of the whole end to end chain. The further away you are from where the hydrogen is produced, the worse it gets.
Anyway, when you multiply all of these efficiencies, you end up with a good reason why hydrogen cars are not a great idea from a cost point of view. Just a lot of losses in this long chain of energy conversions that you necessarily have to do that multiply to lots of energy loss.
What this article proposes is super interesting of course but it doesn't change the math for transport. Battery electric is inherently more efficient. It works today and it's going to only get better. Cheaper more dense batteries, cheaper renewable energy production, etc. There are plenty of more sensible/economical uses for hydrogen outside transport.
I guess you'd also have take into account loss during transmission (which seesm to vary wildly between 2-10% depending on location) and charger efficiency. IIRC if we add it all up it's about 70%.
As for the cars, they can we can install chargers at all parking spots and take advantage of the intermittent energy during the day to charge the cars then. Many colder climates have engine blocker heater outlets as a standard feature for outdoor parking, adding 120V or 240V chargers to new parking spots (and retrofitting old ones) is not a far fetched idea.
The problem is that adds significant energy losses for a hypothetical car powered purely by renewable energy. In fact, it could be even greater than what it takes to power a hydrogen car. That is immediately obvious when you realize that the energy storage system is hydrogen in the first place.
Ultimately, people are just demonizing the inefficiencies of the hydrogen process while totally ignoring real-world losses for battery cars.
Perhaps mid 30% are living in the past. Do you have a reference for the round trip efficiency of a production hydrogen car?
https://ethz.ch/en/news-and-events/eth-news/news/2021/11/hyd...
Quoting "apples to oranges" here ignores the massive inefficiency in other stages of the process of storing and distribution of hydrogen, which is difficult and expensive to do. The distribution of electricity is much more efficient and cheaper.
In fact, this is a total inversion of reality, bordering on science denial. The process of making and storing hydrogen is a straightforward process. It is trying to this with only electricity that is very hard.
You ramp up your hydro output and spread out and postpone the load. People have adapted to doing dishes and laundry when electricity is cheap, this is not different.
Pumped hydro is energy storage that you have to put energy into to push water uphill. And yes it has losses, 25% losses round trip.
If you have a hydroelectric damn however, you increase the flow when the sun doesn't shine or the wind doesn't blow and curtail it otherwise.
> It also requires you to have hydropower.
It's true. Just as wind turbines needs good wind, solar needs ample sunlight, and hydrogen proposals need large underground caverns.
The point is that hydrogen gives you nearly lossless energy storage. This is why simplistic accounts of efficiency are simply wrong. People are ignoring energy storage losses on the BEV side, but always bring up the full cycle losses on the hydrogen side. This is an apples-to-oranges comparison, and gives you an invalid conclusion.