Your first point doesn't make sense to me, there are transmission and discharge losses associated with batteries, but they're still practical for many use cases

Your first point doesn't make sense to me, there are transmission and discharge losses associated with batteries, but they're still practical for many use cases. The amount of tolerable losses depends on how cheap the power is, if the power supply is intermittent, some time they'd be greatly in excess of standard loads, in which case you could run hydrogen cracking at 10% efficiency and it might still be useful just as grid ballast.