Heat load simulation and optimization of the air-conditioning system using EnergyPlus™ / MATLAB® integration

Abstract

In this work, the thermal load of the HSBC laboratory located on the 1st floor of the Alfred Cownley Slater building (building 04) of Mackenzie Presbyterian University (UPM), in Higienópolis, São Paulo, is evaluated, using the EnergyPlus™ simulator interacting with SketchUp®, modeling program, through the Openstudio® plug-in. The simulated thermal load was adjusted and validated for the design loads made available by the Coordination of Works and Maintenance (COMAN) of Mackenzie Presbyterian University (UPM). Simulation results are shown where the shading effect promoted by nearby buildings is evaluated, as well as the effect of changing the thermodynamic state of the outside air. The difference between the thermal load simulated and predicted in the project is less than 1%. The thermal load predicted by EnergyPlus™ was used by a simulator developed in MATLAB® that emulates the operation of a vapor compression cycle. Using the MATLAB® fmincon function optimization feature and programming the vapor compression cycle model as a non-linear programming problem, the operation of the refrigeration system can be optimized. The decision variables of the optimization problem include the opening of the electronic expansion valve of the evaporator, the rotation of the variable speed compressor and the air flow of the condensers of the vapor compression system of the VRV air conditioning system on the 1st floor of the building 04. The optimization of compressor power enables a reduction of up to 14% in energy consumption for the simulation scenarios studied in this work. Thus, it is recommended that additional studies be carried out for the technical-economic assessment of the feasibility of implementing advanced control and optimization strategies in the air-conditioning system of the Alfred Cownley Slater building.