Abstract: A method of managing energy supplied to a facility comprises monitoring a marginal cost of electricity from an electricity vendor; and determining a facility non-heating electrical load and a facility current heating load. The method also comprises obtaining fuel to supply energy to meet the heating load when the marginal cost of electricity is greater than a marginal cost of fuel or the non-heating electrical load is greater than a peak billed demand threshold. When the marginal cost of electricity is less than the marginal cost of the fuel and the non-heating electrical load is less than the peak billed demand threshold, electricity is obtained for the electricity vendor up to the peak billed demand threshold to supply energy to meet at least part of the current heating load, and fuel is obtained to supply energy to meet any current heating load not met by energy from the electricity.

Abstract: A cost-effective method of heating a space in a facility comprises: (a) determining a cost of electricity from an electricity vendor; (b) when the determined cost of electricity is below an electricity pricing setpoint, obtaining sufficient electricity from the vendor to heat a heatable material such as water above a first temperature setpoint; and (c) when the heatable material has a temperature above the first temperature setpoint and a space requires heating, heating the space using at least some of the heat stored in the heatable material. Such method is particularly cost-effective when using electricity charged at a time-of-use basis.