[riversflow]

I'm not particularly thinking of domestic heat production, I agree that heat pumps (ground source, or a pool if you have it, works even better!) are the future of domestic HVAC. I'm thinking about heating for industrial processes, turning off the factory for 30+ minutes during a useage spike is a minor catastrophe if unplanned, you'd either have to design your shift around it (we had time-of-use power pricing and did this) or just close down. I won't rule out heat pumps as being part of the solution out of hand, but from your source:

>Lower output temperature than conventional boilers – you may need to update your insulation and invest in bigger radiators too

is a pretty big problem when you are trying to heat industrial quantities of things up to industrial process temps at industrial rates.