@drvolts how quickly can they start/stop/restart? Is hydrogen a viable sink for excess capacity from peak solar/wind or are there easier ways to use/store that energy?

@drvolts Hydrogen? My questions: How is the cost reduction learning curve looking? What scarce minerals do they need? How long do they last? Can we manufacture and deploy them quickly? What are the main costs for electrolysis, e.g., equipment or electricity or handling the hydrogen? Can they pair well with variable electricity generation and be used when production is plentiful or is continuous use best? Do they work with sea water or does the water need to be processed first?

@drvolts - what are the key hazards and appropriate firefighting practices for electrolyser facility fires, and how should fire risk be best reduced through appropriate siting and design?

@drvolts how much work has to go into the water purification beforehand? Will it work with salt water or brackish water, or do you need to desalinate beforehand to use seawater? (Thinking of places where you have a sunny desert next to an ocean, but not a lot of fresh water.)

@drvolts Will PEM electrolysers (sorry, writing from UK) always use Iridium?

@drvolts Do we need to worry about hydrogen leaks given the warming potential?

@drvolts I think the only important burning electrolyzer question would be how to put out the fire.

@drvolts how would direct seawater electrolysis affect pH? Can we use electrolysis to generate OH to scavenge methane from the atmosphere?

@drvolts What, if any, rare earth metals (conflict minerals) does an electrolyzer contain? what political conflicts exist over that resource, (I'm thinking EV battery lithium is to coups in Ecuador as Electrolyzer minerals are to coups in nnnn country).

@drvolts does it matter that electroayzers are less efficient than the current methane based approaches for producing e.g. ammonia? or can we be taking advantage of spikes in renewables to address this?