It’s still not earning you money to spend electricity because you still have to pay the transfer fee which is around 6 cents / kWh but it’s pretty damn cheap nevertheless, mostly because of the excess in wind energy.
Last winter because of a mistake it dropped down to negative 50 cents / kWh for few hours, averaging negative 20 cents for the entire day. People were literally earning money by spending electricity. Some were running electric heaters outside in the middle of the winter.
There are two solutions to trucks:
The first will almost certainly happen in the next few years. Batteries have been improving kwh/kg at 5-8% per year. There are still enough lab research projects making their way into actual manufactured batteries that we expect this to continue for a while longer. It’s been at the higher end of the range for the last few years. That growth compounds every year; at 8%, you’ve more than doubled capacity in 10 years. Which is about where trucks would need to be.
How much would you want to invest in a parallel set of hydrogen infrastructure and trucks when batteries are likely to overtake them in a few years?
The better solution is to replace most long haul trucking with trains. If the trains kept running on diesel, it’d still be a huge win. Even better is electrified overhead wires, but diesel will do fine if we have to.
The US commercial train system has deliberately avoided competing with most long haul trucking for decades. It doesn’t have to be that way, and the investment needed may not be that much.
As far as grid storage goes, we have flow batteries, pumped hydro, flywheels, heating up sand, or sodium batteries. They all have advantages and disadvantages, but hydrogen doesn’t have much of a niche.
we’re also moving away from wet lithium cell tech and into solid state tech, as well as other non rare metals based technologies, though those are all in the very super alpha states (except for solid state lithium cells)
nickel hydrogen might become something interesting if a company picks it up. Cheap and relatively reliable, though unconventional.
also flywheel energy storage is almost exclusively used for frequency stabilization of the grids, as opposed to actually storing energy. It mechanically couples a source of inertia to the frequency, which in an all renewable grid, is required to some degree.