This won't happen. What will happen instead is that the gas to cook your omelette in the morning will cost three times more than going to a restaurant would and you'll make your own decision about shutting down your gas lines.
This is the same thing I say to petrol heads about gas. Sure, there might be some left for enthusiasts. But enthusiasts alone will not be able to afford the massive economies of scale that make that consumption anything close to affordable.
> so it's very unlikely that synthetic Methane will cost more than a few dozen cents per kWh
No, it’ll cost much more than that. You’re ignoring the factored in cost of storing and distributing gas. This is something that’s only affordable because of economies of scale (and government support) because it was the only practical option for heating and hot water for a while. As electricity gets cheaper and people switch over to heat pumps and electric hot water heaters, the cost of that distribution network is going to fall on fewer people, driving up their cost.
I wouldn’t be surprised if that the gas bill for synthetic methane just for cooking was as high as your current gas bill for heating and cooking. Once economies of scale go away, things get costly fast.
> So you can run a stove for an hour a day for one or two bucks or so. I guess that's several times more than you pay for natural gas, but a lot cheaper than going to a restaurant.
Sure. But the competitor to a natural gas stove isn’t eating out, it’s electricity. Especially as gas gets more expensive and induction ranges become the norm.
Not sure where you live, but in my country the plan is to get everyone off gas by 2050. At that time the national gas network should be shut down.