Life Cycle Assessment (LCA) of an Innovative Compact Hybrid Electrical-Thermal Storage System for Residential Buildings in Mediterranean Climate

Abstract

The buildings sector is one of the least sustainable activities in the world, accounting for around 40% of the total global energy demand. With the aim to reduce the environmental impact of this sector, the use of renewable energy sources coupled with energy storage systems in buildings has been investigated in recent years. Innovative solutions for cooling, heating, and domestic hot water in buildings can contribute to the buildings’ decarbonization by achieving a reduction of building electrical consumption needed to keep comfortable conditions. However, the environmental impact of a new system is not only related to its electrical consumption from the grid, but also to the environmental load produced in the manufacturing and disposal stages of system components. This study investigates the environmental impact of an innovative system proposed for residential buildings in Mediterranean climate through a life cycle assessment. The results show that, due to the complexity of the system, the manufacturing and disposal stages have a high environmental impact, which is not compensated by the reduction of the impact during the operational stage. A parametric study was also performed to investigate the effect of the design of the storage system on the overall system impact.

Effect of Climate Change and Occupant Behaviour on the Environmental Impact of the Heating and Cooling Systems of a Real Apartment. A Parametric Study through Life Cycle Assessment

“…In general, the impact of the heat pump appears to be always higher than that of the gas boiler. It is in accordance with previous studies, such as [17,19]. In fact, the environmental impacts of the heat pump ranged from 180 kgCO2-eq/m 2 (GWP 20a) to 81 kgCO2eq/m 2 (GWP 100a), far higher than those of the gas boiler that reached 30 kgCO2-eq/m 2 for In general, the impact of the heat pump appears to be always higher than that of the gas boiler.…”

“…The results of the analysis, performed through the ReCiPe and the IPCC global warming potential GWP indicators, showed that the total impact of the innovative hybrid energy storage system was lower than the reference one. Zsembinszki et al [19] compared the environmental performance of an innovative compact hybrid electrical-thermal storage system and a traditional system for cooling, heating, and domestic hot water production in the Mediterranean context. The authors obtained a relevant reduction in energy consumption during the operational stage with the innovative system, despite the environmental impact during its entire life cycle (30-years lifespan) being almost double than that of the traditional system.…”

“…The lifetime of the entire analysis was assumed to be 90 years, while the lifespan and the number of replacements of each system during the 90 years were calculated according to the lifetime of the various systems. Conventionally, the LCAs of products or buildings are performed with a lifetime ranging from 30 to 50 years [12,18,19,53,54], without considering any external variations (e.g., climate change) to the system boundary that could alter the environmental impact of the systems or the buildings. Following the conventional methodology, the LCA for 90 years (hereinafter referred to as LCA b ) was assessed by considering the same weather data for the entire period, as shown in Figure 2a.…”

“…In the end, the LCA for the entire lifetime of 90 years (hereinafter referred to as LCAcc) was calculated as the sum of three contributions: LCA 1, LCA 2, and LCA 3, as shown in Figure 2b. Based on previous studies carried out in this field [12,18,19,53], the functional unit of 1 m 2 of usable floor area was adopted in this analysis. The scope of the study is from 'cradle to grave'.…”

“…Based on previous studies carried out in this field [12,18,19,53], the functional unit of 1 m 2 of usable floor area was adopted in this analysis. The scope of the study is from 'cradle to grave'.…”