An optimization mode for industrial load management

Abstract

This paper presents a physically based model and formulation for industrial load management. The formulation utilizes integer linear programming technique for minimizing the electricity costs by scheduling the loads satisfying the process, storage and production constraints. The proposed strategy is evaluated by a case study for a typical flour mill with different load management options. The results show that significant reductions in peak electricity consumption are possible under time of use tariffs.

A model predictive control strategy for load shifting in a water pumping scheme with maximum demand charges

“…The optimization techniques (open loop optimal control models) used in [25]- [32] are valuable starting points to quantify the potential for load shifting. However, they cannot actively control a load shifting process with disturbances.…”

“…The optimization techniques used in [25]- [32] do not consider external disturbances or inaccurate system models. In other words, no feedback and subsequent re-optimization is included to compensate for these deficiencies.…”

“…This type of controller is referred to as a closed-loop optimal controller [37]. Table 2-1 shows that the load shifting techniques in [25]- [36] can be further categorized as follows: [25]- [27] considers optimization (open loop optimal control) with TOU charges, [28]- [32] considers optimization (open loop optimal control) with TOU and MD charges, [33] and [34] considers closed-loop optimal control models with TOU charges, and only [35] and [36] considers closed-loop optimal control models with TOU and MD charges.…”

“…In [25] an open loop optimal control model is applied to a flour mill in India that is charged on both TOU and MD. However, the MD charge is not included in the objective function of the optimal control model.…”

“…A neural network is used in [24] for load shifting in a petrochemical plant. In [25]- [32] load shifting problems are modelled as optimization problems, and in [33]- [36] load shifting problems are modelled as optimal control problems [8], [9].…”