There's a whole industrial technology -- bulk resistive heat storage -- that's popping up to deal with intermittent low or negative power prices. Temperatures as high as 1800 C can be stored in resistively heated refractory materials, then used to displace fossil fuel combustion in various industrial processes. The stored energy/mass and energy/cost in such materials can be very high.
Yeah if you're calcining concrete clinker you'll happily use resistive heating if electricity is cheaper than nat gas.
I like to bitch about people that think the free market solves everything but oh noes the price of electricity is negative is one thing I think the free market can totally solve.
