Building energy storage system with peak load contribution and stochastic cost optimization

A method for allocating one or more resources in a central plant, the method comprising:

• obtaining a cost function comprising a peak load contribution (PLC) term, wherein the PLC term represents a cost based on an amount of the one or more resources purchased from the utility during coincidental peak (CP) subperiods of an optimization period comprising a plurality of time steps, the CP subperiods comprising a subset of the plurality of time steps, wherein the cost is a function of one or more decision variables representing an amount of the one or more resources to store in one or more storage devices or to discharge from the one or more storage devices during each of the plurality of time steps;
• modifying the cost function by applying a peak subperiods mask to the PLC term, wherein the peak subperiods mask identifies one or more subperiods in the optimization period as projected CP subperiods and causes the one or more resources purchased from the utility during any subperiods not identified as projected CP subperiods to be assigned substantially zero cost in the PLC term;
• generating a plurality of variations of the peak subperiods mask, each variation corresponding to one of a plurality of scenarios;
• allocating, to each of the time steps within the optimization period, an amount of the one or more resources to store in the one or more storage devices or discharge from the one or more storage devices during the time step by performing an optimization of the modified cost function over the plurality of scenarios to determine values of the decision variables.

An energy cost optimization system for a building, the system comprising:

• HVAC equipment configured to consume one or more resources purchased from a utility or generated by a central plant for use in satisfying a building energy load;
• and
• a controller configured to:
• obtain a cost function comprising a peak load contribution (PLC) term, wherein the PLC term represents a cost based on an amount of the one or more resources purchased from the utility during coincidental peak (CP) subperiods of an optimization period comprising a plurality of time steps, the CP subperiods comprising a subset of the plurality of time steps in the optimization period, wherein the cost is a function of one or more decision variables representing an amount of the one or more resources to be consumed by the HVAC equipment during each of the plurality of time steps;
• modify the cost function by applying a peak subperiods mask to the PLC term, wherein, for each subperiod of a plurality of subperiods in the optimization period, the peak subperiods mask modifies a portion of the PLC term corresponding to the subperiod based on a probability that the subperiod will be one of the CP subperiods;
• and
• allocate, to each of the time steps within the optimization period, an amount of the one or more resources to be consumed by the HVAC equipment during the time step by performing an optimization process of the modified cost function to determine values of the decision variables.