Modern heat pumps provide a lot more than 100% efficiency. I'd stick to the heating system unless those containers are doing something profitable (mining?)
Thermodynamics would not take kindly to you having a >99.999...% efficient anything.
Coefficient of performance is a type of efficiency.
> modern heat pumps reach their CoP because they don't actually generate heat, they simply move it around
That's not even true! What a mess of a pedantic correction.
> Thermodynamics would not take kindly to you having a >99.999...% efficient anything
Well the cogen gas powerplants here can produce 50kWh of electricity from burning 100kWh of natural gas. I can use 50kWh of electricity to put 200kWh of heat into my house with a heatpump.
Seems like a good deal to me, and I think carnot would be fine with that.