Combined Effect of Outdoor Microclimate Boundary Conditions on Air Conditioning System’s Efficiency and Building Energy Demand in Net Zero Energy Settlements

Abstract

In Europe, near zero energy buildings (NZEBs) represent the new frontier of energy efficiency in the built environment. Shifting the scale from NZEBs to net zero energy (NZE) settlements represents the opportunity to achieve further energy, environmental, and cost benefits, thanks to shared energy management, optimization of renewable energy systems, and microclimate mitigation. In particular, the last aspect takes advantage of the implementation of local microclimate mitigation strategies at a larger scale to improve settlements outdoor environmental conditions and citizens’ wellbeing. Furthermore, this inter-building scale mitigation involves relatively less severe working boundary conditions for buildings, able to both reduce building energy demand and improve HVAC (heating, ventilation, and air conditioning) system’s efficiency. In this study, this potential extra-energy saving, achievable without additional costs, is explored within the framework of a NZE settlement built in Italy thanks to an ongoing Horizon 2020 project. Improved working conditions for the operating air conditioning system and building energy savings thanks to settlement scale opportunities for microclimate mitigation are assessed. Findings show how this effect represents a further non-negligible energy-efficient and environmentally sustainable benefit achievable through the design and construction of NZE settlements. Potential energy savings are up to 24% when considering the double effect of microclimate mitigation.

كفاءة الطاقة لأنظمة التكييف التقليدية في ظل تغير المناخ

“…When multiple control loops are working at the same time, they can affect each other. In order to minimize the interference between these control loops, Wang and Wang have designed a compensation unit that is designed to provide a decoupling effect (Piselli et al, 2020).…”

Measurement and Verification of Zero Energy Settlements: Lessons Learned from Four Pilot Cases in Europe

“…The deviation between design and actual building performance, known as the performance gap, has been well established in the literature [9][10][11], and is a strong driver for performing M&V [12]. Through measuring and analyzing actual performance, data can be fed back into simulation models allowing the quantification and evaluation of the performance gap [9], as well as the identification of causes and consequent mitigating actions [10,11], such as lack of precision in the definition of realistic boundary conditions at building and settlement level [13]. The measured performance also provides feedback to occupants, thus assisting the transition of occupant behavior to an energy-conscious mindset and enhancing the success of the applied energy strategies and further assisting in closing the performance gap [14].…”

Thermal Technical Analysis of Lightweight Timber-Based External Wall Structures with Ventilated Air Gap

“…Another advantage of wood-based constructions is their sustainability. This is mainly due to the fact that almost forty percent of all energy in Europe is consumed by buildings [5,6]. It is for this reason that the share of timber-based structures has been growing in recent years as part of buildings envelope.…”