There will come a time where we have excess power to burn but the fleeting nature of renewables will require that we store this energy somehow, which I fully believe that hydrogen will play a role in as you are able to create it at a rate proportional to energy you put in, which is more important that efficiency. Batteries will not scale to our needs at more than a micro-grid level. Scaling hydrogen production will bring down the marginal cost of producing each unit.
Remember that current battery tech was not as easy to produce as it is today for precisely the same reasons I am hypothesizing that fuel cell technology will become easier and cheaper to produce and more efficient in its operation so I will just reiterate this from my post:
> Complaining that a solution is inefficient, which has not been innovated on, is small-minded thinking.
Batteries have their limitations, they require specific materials, slow to charge, and difficult to recycle. Hydrogen is the most abundant substance in the universe, and just needs to be crested and stored.
We will eventually get to point with solar that we will have excess energy that needs to be used but nothing to consume it. Modern hydrogen electrolysis is about 80% and once the hydrogen is stored, using a hydrogen fuel cell to generate electricity is about 60% efficient. That’s a 48% efficient process which is still better than 0% by letting that energy go unused.
This space has not seen significant innovation because it has not been a major focus. Given a significant political or economic force, we can bring the efficiency up, waste down, and standardize hydrogen containment and pressure systems. Complaining that a solution is inefficient, which has not been innovated on, is small-minded thinking.