Yes, of course power sinks gain value from having their own power buffer, even if only to take advantage of fluctuations in energy cost. But why would this caus

Yes, of course power sinks gain value from having their own power buffer, even if only to take advantage of fluctuations in energy cost. But why would this cause grid collapse? They still need the energy delivered, at some point. It puts whoever runs the grid in the quite enviable position of power market middleman. Far from collapsing, I would expect grids to do extremely well out of such a shift.