Review of cost objective functions in multi-objective optimisation analysis of buildings

Notwithstanding the reductions in the cost of renewable energy per unit produced, cost objectives remain a relevant yet understudied topic due to their ability to indicate information available in the market. To better understand the general practice and identify trends in cost objectives for renewable energy-powered buildings in multi-objective optimisation problems, the article systematically reviews 129 studies published in 2011-2023 and identifies the highly cited articles (N = 23) to be reviewed narratively. As for the contribution to the literature, cost objectives are re-categorised based on the cost components considered. Assigned categories show that the authors focus on initial costs and energy costs. Systematic analysis shows that the most popular original metrics are total (life cycle cost, total costs) and energy import costs. There seems to be little association between climate zone and metric considered, but the payback period is applied in less developed countries. Supplementary economic objective metrics are on the rise. To further aid decision-making and address the current limitations - oversimplification of the project context, transitioning towards a managerial accounting perspective is welcomed. It could aid in attracting investment from other than project developers' sources, to reach the target investment in building energy efficiency required for the 1.5-degree target by 2050.