Cost-Effective, Energy-Efficient Solutions for Building Envelope: A Multi-Objective Optimization Case Study

Abstract

The renovation of a building entails not just the fulfillment of functional demands, but also considerations such as investment costs, energy consumption, and occupant well-being. Building energy retrofitting should pursue “cost-optimal levels.” To do so, the present study proposes a method aimed at “defining the energy performance of buildings’ shells” with ‘optimal cost levels.’ With this aim, the multi-objective optimization method is adopted. Using the genetic algorithm, the optimization method a connection is defined between the optimization algorithm in the jEplus software (as the optimization engine) and the EnergyPlus™ software (as the simulation engine), and allows the designer to evaluate a range of different options and select the best. In this paper, a developed method for energy optimization of reference buildings is conducted. Simulation-based simulation results indicate that the energy saving rate in the four different climates of Iran is 29% to 58% lower than the base model. One of the results available can be best suited for expert judgment or decision making.