EnergyPlus Simulation Speedup Using Data Parallelization Concept

EnergyPlus is an energy simulation tool which models heating, cooling, lighting, ventilation, and other energy flows in buildings. It is based on the popular features of BLAST and DOE-2. Though EnergyPlus is more advanced than DOE-2, it comes with a drawback of larger simulation runtime. According to a previous study conducted by Tianzhen Hong, et al [1], at a 60-minute time step, EnergyPlus runs slower than DOE-2.1E by a factor of 25 for a large office building to 54 for a hospital building. A decrease in the simulation runtime of EnergyPlus would increase the usability of the software. In this paper, a concept has been proposed which uses data parallelization to speed up EnergyPlus simulation. Data parallelization is a form of parallelization for computing across multiple processors or multiple computers in a cluster, run under a suitable environment. Data parallelism focuses on distributing the data across different parallel computing nodes by breaking it into smaller chunks, each of which is processed on by the same function, running in parallel on different cores/machines. In the proposed concept, this is achieved by breaking a simulation with annual RunPeriod into several simulations of smaller RunPeriod, each handled by a separate computer. Each computer instead of running an annual simulation, handles a chunk of smaller RunPeriod, say one month, thus taking lesser time. This paper discusses the concept and presents the results of the preliminary investigations. It has been observed that a speed gain of approximately 4 times can be achieved by this method.