I was recently at a party with a SNES connected to a noisy channel-3 RF modulator because the TV couldn’t switch to its composite input via the front panel buttons, and they didn’t have the remote. I wandered the house until I found a universal remote, then programmed AUX to match the TV and switched inputs. Just things you learn in the '90s.
8.5 GWh / 85 MW = 100 hours, or around 4 days. If they can build it cheap enough, this is the kind of battery we would need to replace nuclear for dealing with the day-to-day variability of renewables.