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Building ventilation systems are equipped to improve indoor air quality (IAQ) through bringing in the non-polluted outdoor air for occupants. Carbon dioxide (CO2) concertation level serves as one of the most critical indicators for IAQ and occupancy to control ventilation systems. Many control strategies (such as ASHRAE standard 62.1) utilize CO2 concertation to determine the necessarily supplied air amount in building space. However, many studies suggest that due to the CO2’s mixed dual functions in indicating IAQ and occupancy, a large discrepancy is observed between the CO2 estimated occupancy and actual occupancy, especially in space with multiple zones. These estimation errors not only result in inefficient control response but also wasted fan power in unoccupied space. To solve those problems, this study utilized indoor positioning system (IPS) to detect occupancy and select the critical zones. The proposed control strategy calibrates the outdoor air flow based on detected zone occupancy. To validate the proposed strategy, this study compared the outcomes with conventional pure CO2 based control strategy. The simulation results suggest the proposed method could achieve acceptable CO2 concentration under 1000ppm for most zones and over 25% energy saving from primary fans and cooling coil during a sample weekday and a sample weekend day. [ABSTRACT FROM AUTHOR]

The built environment contributes significantly to rapidly growing world energy expenditure and tighter spatial interrelationships can exacerbate this effect in cities. The concept of the Inter-Building Effect (IBE) was introduced to understand the complex mutual impact within spatially proximal buildings. Our research sought to develop a systematic approach to disaggregate and quantify the influence of mutual shading and mutual reflection within a network of buildings. We built an urban building network model and conducted cross-regional simulations under different climatological contexts by examining mutual shading only and mutual reflection only, respectively. We then expanded our investigation by examining two realistic urban contexts in Perugia, Italy. We found the shading effect played a more significant role in terms of impact on energy consumption. The results of the simulations in varying climatological contexts also revealed consistent trends of greater impact on the IBE for shading and reflection in warmer climatic cities. These findings expand and deepen our understanding of inter-building effects and may help in the search to minimize mutual influences between buildings that lead to increases in energy consumption in urban environments. [ABSTRACT FROM AUTHOR]

The built environment contributes significantly to rapidly growing world energy consumption. Along with urbanization, buildings continue to escalate this trend owing to their tighter spatial interrelationships and the influence of their surrounding micro-environment. The concept of the Inter-Building Effect (IBE) was introduced to understand complex mutual impacts within spatially-proximal buildings. Recent research has revealed that inter-building reflection or shading can have nuanced effects on a month-by-month basis depending on the climatological context. The application of phase change materials (PCMs) has begun to be examined by researchers due to its ability to store and release heat within a certain temperature range. In this paper, we sought to explore and understand if PCM-embedded building envelopes could potentially mitigate negative thermal-energy impacts within spatially proximal buildings. Building upon previous IBE research and simulation models, we conducted several building network simulations with different PCM settings in different climatological contexts. The results showed considerable improvements (up to 17%) of annual HVAC energy consumption when PCM-embedded building envelopes were used in the control building. The findings expand and deepen our understanding of the IBE, and may help minimize negative mutual influences across buildings that lead to increases in energy consumption in urban environments. [ABSTRACT FROM AUTHOR]

The built environment contributes significantly to rapidly growing world energy consumption. Along with urbanization, buildings continue to escalate this trend owing to their tighter spatial interrelationships and the influence of their surrounding micro-environment. The concept of the Inter-Building Effect (IBE) was introduced to understand complex mutual impact within spatially-proximal buildings. Disaggregate analysis further quantified shading effects and reflection effects separately from combined IBE interaction in a more nuanced way. Different from tropical cities where mutual reflection always shows a negative impression, recent research revealed more complex scenarios in non-tropical areas as the reflection or shading could become favorable month by month alternately according to climatological contexts. The application of phase change materials (PCMs) has attracted attention due to its important characteristic to store and release heat within a certain temperature range. A variety of research has been conducted for building applications to improve energy conservation and thermal comfort both numerically and empirically. In this paper, we sought to explore and understand if PCM building envelopes could potentially mitigate negative thermal-energy impact within building canyons in a non-tropical area. Building upon previous IBE research and simulation models, we conducted several building network simulations under different climatological contexts of non-tropical cities. The results showed considerable improvements (up to 12%) of annual HVAC energy consumption when PCM-embedded building envelopes were used in the control building. The findings expand and deepen our understanding of the IBE, and may help minimize negative mutual influences among buildings that lead to increases in energy consumption in urban environments. [ABSTRACT FROM AUTHOR]

The built environment contributes significantly to the rapidly growing world energy expenditure. Due to urbanization, buildings will continue to contribute to these escalating trends because of their tighter spatial interrelationships, and the influence of their surrounding micro-environment with respect to their orientations and designs. The concept of the Inter-Building Effect (IBE) was introduced to understand such complex mutual impact within spatially proximal buildings. As an extension and a more nuanced analysis of the IBE, our research sought to disaggregate and quantify the influence of mutual shading and mutual reflection within a network of buildings. A procedure to separately assess the complex interactions that make up the IBE was developed by comparative simulation and analysis in a dynamic simulation environment. We built an urban building network model and conducted cross-regional analysis under different climatological contexts by examining mutual shading only and mutual reflection only, respectively. We found the shading effect played a more significant role in terms of impact on energy consumption. This resulted in substantial variations for the control building's energy consumption when the shading effect was disaggregated from the IBE. The results of the simulations in varying climatological contexts also revealed consistent trends of greater impact on the IBE for shading and reflection in warmer climatic cities. These findings expand and deepen our understanding of the IBE and may help in the search to minimize mutual influences between buildings that lead to increases in energy consumption in urban environments. [ABSTRACT FROM AUTHOR]