Sensitivity of buildings’ carbon footprint to electricity decarbonization: a life cycle–based multi-objective optimization approach
Sensitivity of buildings’ carbon footprint to electricity decarbonization: a life cycle–based multi-objective optimization approach
复制标题
DOI：
10.1007/s11367-022-02043-y
复制
发表时间：
2022-04
期刊：
影响因子：
--
通讯作者：
B. Kiss;Z. Szalay
中科院分区：
文献类型：
--
作者：
B. Kiss;Z. Szalay
目的生命周期评估（LCA）是一种广泛使用的评估建筑物环境影响的方法，但这些分析包含高度的不确定性。电力生产脱碳是实现气候目标的关键，影响包括建筑业在内的所有行业。本文的目的是研究环境优化建筑设计解决方案对不断变化的电力结构的敏感性，以协助决策。方法本文采用多目标优化，利用动态能源模拟和生命周期分析，同时最大限度地减少建筑物的生命周期全球变暖潜势和生命周期成本。这些变量包括建筑围护结构参数，例如用热泵供暖的典型新型多户公寓楼的窗户比例、隔热类型和厚度。考虑了静态的、主要基于化石的电力组合和动态的、逐渐脱碳的替代方案，以及两种电价上涨情景。引入了新的指标来探索结果并描述帕累托最优解决方案，例如通过优化将成就背景化的改进潜力。结果和讨论结果表明，与典型的新设计相比，在当前的电力结构下，建筑围护结构优化可以将生命周期温室气体排放量平均提高 18%，而在匈牙利的动态混合设计中可以提高 10%。对于当今的静电组合，优化证明现行的最低能效要求接近成本最优。然而，从环境角度来看，更高的隔热厚度已被证明是合理的（U 值小于 0.1 W/m2K）。结论基于 LCA 的建筑设计优化仍未得到广泛应用，并且脱碳电力组合对优化的影响之前尚未研究过。论文的结果证明了这个问题的重要性。最佳解决方案根据应用的组合而有所不同，但节能的建筑围护结构仍然很重要：从长远来看，当今成本最优的建筑围护结构被证明是成本和环境最优的。
PurposeLife cycle assessment (LCA) is a widely used method for the evaluation of buildings’ environmental impacts, but these analyses contain high levels of uncertainty. Decarbonization of electricity production is key to reach climate goals, influencing all sectors including construction The objective of this paper is to study the sensitivity of the environmentally optimum building design solution to a changing electricity mix to assist decision-making.MethodsIn this paper, multi-objective optimization was applied to minimize the life cycle global warming potential and life cycle costs of a building at the same time, using dynamic energy simulation and LCA. The variables include building envelope parameters such as window ratio, insulation type and thickness in a typical new multi-family apartment building heated with a heat pump. A static, largely fossil-based electricity mix and a dynamic, gradually decarbonizing alternative are considered, as well as two electricity price increase scenarios. New metrics have been introduced to explore the results and describe the Pareto-optimal solutions, for example the improvement potential to contextualize the achievements through the optimization.Results and discussionThe results show that, with the current electricity mix, building envelope optimization can improve the design by 18% on average in terms of the life cycle greenhouse gas emissions compared to typical new designs and by 10% with a dynamic mix in Hungary. With today’s static electricity mix, the optimization proved that the minimum energy efficiency requirements in force are close to cost optimality. However, from an environmental point of view, much higher insulation thicknesses have been shown as justified (U-values of less than 0.1 W/m2K).ConclusionsOptimization of building design based on LCA is still not widely applied and the effect of a decarbonizing electricity mix on the optimum has not been studied before. The results of the paper demonstrate the importance of this question. Optimal solutions are different depending on the applied mix but an energy-efficient building envelope remains important: today’s cost-optimal building envelope proves to be both cost- and environmentally optimal in the long run.