A target-driven decision-making multi-layered approach for optimal building retrofits via agglomerative hierarchical clustering: A case study in China

Abstract

The optimisation of energy, environmental and economic (3E) outcomes is the principal approach to identifying retrofit solutions for a sustainable built environment. By applying this approach and defining a set performance target, this study proposes a makeshift decision framework that integrates a data mining procedure (agglomerative hierarchical clustering (AHC)) into the multi-objective decision-making process to provide a simplified 3E assessment of building retrofits on a macro-scale. The framework comprises of three methodological models: (1) a building stock aggregation model, (2) an individualistic 3E model that provides the sensitivity analysis for (3) a life cycle cost-environmental assessment model. The framework is demonstrated and validated with a case study aimed at achieving the set EUI targets for low-rise office buildings (LOB) in Shanghai. The model defines 4 prototypical buildings for the existing LOB blocks, which are used for the individual evaluation of 12 commonly applied retrofit measures. Subsequently, a simplified LCC-environmental assessment was performed to evaluate the 3E prospects of 2048 possible retrofit combinations. The results uniquely identify retrofit solutions to attain set performance targets and optimal building performance. Furthermore, the decision criteria for different investment scenarios are discussed. Overall, this study provides building investors an innovative framework for a facile and holistic assessment of a broader range of retrofit alternatives based on set performance targets. .

Coordinated energy-environmental-economic optimisation of building retrofits for optimal energy performance on a macro-scale: A life-cycle cost-based evaluation

“…Here, an LCC-environmental evaluation approach using simplified numerical simulations is employed to identify the optimal retrofit strategy. Theis optimal strategy should not only be determined by the original capital of the investors but also, to maximise the life-cycle benefits of the retrofits [17]. Simply put, the investors can select the solution with the minimum total/life-cycle cost as the optimal retrofit strategy [10].…”

“…Optimal retrofit strategy (upgrade level) in terms of the minimum LCC (TC) evaluation for (a) C1W2F5, (b) C2W1F3, (c) C2W3F4, and (d) C2W3F6 building models [17]. The table layout displayed in this section is not how it will appear in the final version.…”

“…In summary, an energy-efficient retrofit framework (ERF) with a thorough 3E evaluation and optimisation approach is required to establish a realistic retrofit solution on a macro-scale. Furthermore, emphasis should be on the economic impact (cost parameters) as a more pragmatic indicator for optimizing life-cycle benefits [17].…”

“…In summary, an energy-efficient retrofit framework (ERF) with a thorough 3E evaluation and optimisation approach is required to establish a realistic retrofit solution on a macro-scale. Furthermore, emphasis should be on the economic impact (cost parameters) as a more pragmatic indicator for optimizing life-cycle benefits [17].Hence, this study presents an ERF with a facile 3E multi-objective optimisation approach at the building level to estimate the effect of micro-scale retrofitting on a macroscale intervention. The proposed framework involves coordinated approaches formulated to study the operational performance and determine the optimal retrofit solution for existing building stocks, with a focus on the economic evaluation.…”