Indoor Environmental Performance Research Articles

Continuous monitoring of indoor environmental quality using an Arduino-based data acquisition system

Building performance monitoring could be limited due to the cost and inflexibility of hardware and software platforms for data acquisition. This paper describes a portable continuous measurement toolbox which provides a robust, easily extendable, and low-cost setup for indoor environmental quality (IEQ) monitoring and performance assessment. Various sensors—temperature, relative humidity, illuminance, CO2, VOC, PM2.5, and occupancy—for IEQ performance measurement are included in this toolbox. Arduino Uno boards were connected to the sensors for data acquisition. ZigBee communication protocol was established between an XBee device for each Arduino board and an XBee receiver connected to a computer. The toolbox utilized the open source, agent-based software platform VOLTTRON for data communication and analysis. The data collection system was calibrated against an accurate data acquisition card. Experiments have been conducted using the toolbox for assessing IEQ performance in an open computer lab within a commercial building. Thermal comfort, indoor air quality, and lighting performance have been analyzed based on collected data. The study demonstrated reliability and robustness of the toolbox for continuous monitoring of indoor environmental quality.

Prediction of Human Performance Using Electroencephalography under Different Indoor Room Temperatures

Varying indoor environmental conditions is known to affect office worker’s performance; wherein past research studies have reported the effects of unfavorable indoor temperature and air quality causing sick building syndrome (SBS) among office workers. Thus, investigating factors that can predict performance in changing indoor environments have become a highly important research topic bearing significant impact in our society. While past research studies have attempted to determine predictors for performance, they do not provide satisfactory prediction ability. Therefore, in this preliminary study, we attempt to predict performance during office-work tasks triggered by different indoor room temperatures (22.2 °C and 30 °C) from human brain signals recorded using electroencephalography (EEG). Seven participants were recruited, from whom EEG, skin temperature, heart rate and thermal survey questionnaires were collected. Regression analyses were carried out to investigate the effectiveness of using EEG power spectral densities (PSD) as predictors of performance. Our results indicate EEG PSDs as predictors provide the highest R2 (> 0.70), that is 17 times higher than using other physiological signals as predictors and is more robust. Finally, the paper provides insight on the selected predictors based on brain activity patterns for low- and high-performance levels under different indoor-temperatures.

Clearing the air on EU guidance projects for school buildings

ABSTRACT Professionals engaged in the design of new or retrofit of existing school buildings currently struggle to find comprehensive guidelines for achieving healthy and energy-efficient school environments. Recently, two major and independent research projects aimed at improving indoor environmental quality and energy performance of school buildings in Europe have been completed: SINPHONIE and School of the Future. Their guidelines reflect the distinct priorities and limited scope of each project. This paper compares for the first time and, as far as possible, synthesizes these outputs to facilitate their use in practice and research. Overall, SINPHONIE is most useful in addressing indoor environmental quality of schools in terms of the physical, chemical and microbiological stressors that impact and potentially affect human health. It aims to influence the future development of policy and regulations. By contrast, School of the Future presents a broader design-oriented approach based on best practice in four European countries. For the most part they complement each other in their recommendations; however, this review highlights several areas that require further clarification and research including links between indoor environmental quality and cognitive performance, the consequent appropriate level for the designed ventilation rate, and the role of adaptive thermal comfort in schools.

THE INDOOR ENVIRONMENTAL QUALITY PERFORMANCE OF GREEN LOW-INCOME SINGLE-FAMILY HOUSING

There is little empirical evidence in the literature about the indoor environmental quality performance of residential buildings in general and of social housing in particular. To address this problem, this study used a mixed-method approach to evaluate the indoor environmental quality performance of 17 green low-income single attached family houses in Brandon, Manitoba, Canada. Questionnaires were administered to occupants to assess their snapshot and long-term satisfaction with the indoor environment. In addition, snapshot measurements were carried out to evaluate the indoor environmental quality factors of thermal comfort, indoor air quality, lighting and acoustics. Occupants' snapshot satisfaction was categorized into two groups (i.e. satisfied/comfortable or dissatisfied/uncomfortable) and compared with snapshot measurements. The results showed the measured IEQ parameters were well below recommended threshold levels. Further, occupants with higher snapshot satisfaction were generally exposed to relatively lower levels of indoor pollutants. A statistically significant difference was found in PM10 level only between the snapshot satisfied and snapshot dissatisfied groups of occupants. Apparent sound transmission classes were below the standard reference value of 50, suggesting potential problems in noise attenuation within different spaces in each apartment and between apartments. The findings of this study could help governments implement green shadowing for public-housing and also renovate existing houses using the same principles.

A Survey of Positioning Systems Using Visible LED Lights

As Global Positioning System (GPS) cannot provide satisfying performance in indoor environments, indoor positioning technology, which utilizes indoor wireless signals instead of GPS signals, has grown rapidly in recent years. Meanwhile, visible light communication (VLC) using light devices such as light emitting diodes (LEDs) has been deemed to be a promising candidate in the heterogeneous wireless networks that may collaborate with radio frequencies (RF) wireless networks. In particular, light-fidelity has a great potential for deployment in future indoor environments because of its high throughput and security advantages. This paper provides a comprehensive study of a novel positioning technology based on visible white LED lights, which has attracted much attention from both academia and industry. The essential characteristics and principles of this system are deeply discussed, and relevant positioning algorithms and designs are classified and elaborated. This paper undertakes a thorough investigation into current LED-based indoor positioning systems and compares their performance through many aspects, such as test environment, accuracy, and cost. It presents indoor hybrid positioning systems among VLC and other systems (e.g., inertial sensors and RF systems). We also review and classify outdoor VLC positioning applications for the first time. Finally, this paper surveys major advances as well as open issues, challenges, and future research directions in VLC positioning systems.

Comparison of building performance between Conventional House and Passive House in the UK

The building performance monitored over one year of a Conventional House and a Passive House in North East England is presented in this paper. These two houses which differ in building fabric, the type of ventilation and thermal storage, the use of different energy and residents’ occupancy result in distinct building energy performance and indoor air quality. According to the measurement data, the primary energy demand of the Conventional House and Passive House were 169.85 kWh/(m2a) and 64.11 kWh/(m2a) while the annual average indoor temperature of the two properties maintained at 17.7°C and 22.0°C, respectively. A simulation study was conducted by DesignBuilder software to improve the Conventional House’s energy and indoor environmental performance using passive retrofitting methods, aiming to reduce the primary energy demand, the space heating demand of the property and enhance its general indoor air environmental performance. The DesignBuilder models were validated by monitored data and used to predict the performance of the Conventional House after retrofitting, and then compared it with the Passive House. The results indicate the reduction of space heating demand is by about 80% compared to its current status. The findings showed that there was a huge potential for conventional house retrofitting using passive energy saving methods in northern England.

次世代都市型病院の室内環境・エネルギー性能の検証・評価研究 （第1報）施設の概要と計画コンセプト

次世代都市型病院の室内環境・エネルギー性能の検証・評価研究 （第1報）施設の概要と計画コンセプト

次世代都市型病院の室内環境・エネルギー性能の検証・評価研究 （第2報）熱源システムの性能検証・評価（設計・施工（試運転調整）段階におけるLCEM検討）

次世代都市型病院の室内環境・エネルギー性能の検証・評価研究 （第2報）熱源システムの性能検証・評価（設計・施工（試運転調整）段階におけるLCEM検討）

次世代都市型病院の室内環境・エネルギー性能の検証・評価研究 （第3報）室内環境の評価・検証（施工（試運転調整）段階における病室環境の計測）

次世代都市型病院の室内環境・エネルギー性能の検証・評価研究 （第3報）室内環境の評価・検証（施工（試運転調整）段階における病室環境の計測）

次世代都市型病院の室内環境・エネルギー性能の検証・評価研究 （第9報）運用開始後1年間の水・エネルギー消費実績

次世代都市型病院の室内環境・エネルギー性能の検証・評価研究 （第9報）運用開始後1年間の水・エネルギー消費実績

次世代都市型病院の室内環境・エネルギー性能の検証・評価研究 （第13報）地中熱ヒートポンプシステムの運転適正化と実運転性能評価

次世代都市型病院の室内環境・エネルギー性能の検証・評価研究 （第13報）地中熱ヒートポンプシステムの運転適正化と実運転性能評価

次世代都市型病院の室内環境・エネルギー性能の検証・評価研究 （第8報）地中熱利用ヒートポンプシステムのシミュレーションモデル構築

次世代都市型病院の室内環境・エネルギー性能の検証・評価研究 （第8報）地中熱利用ヒートポンプシステムのシミュレーションモデル構築

次世代都市型病院の室内環境・エネルギー性能の検証・評価研究 （第12報）熱源システムの継続的性能評価

次世代都市型病院の室内環境・エネルギー性能の検証・評価研究 （第12報）熱源システムの継続的性能評価

次世代都市型病院の室内環境・エネルギー性能の検証・評価研究 （第10報）性能検証・評価期間における水・エネルギー消費実績と評価

次世代都市型病院の室内環境・エネルギー性能の検証・評価研究 （第10報）性能検証・評価期間における水・エネルギー消費実績と評価

次世代都市型病院の室内環境・エネルギー性能の検証・評価研究 （第15 報）竣工後3 シーズン目における加湿方式による空調給気清浄度の評価

次世代都市型病院の室内環境・エネルギー性能の検証・評価研究 （第15 報）竣工後3 シーズン目における加湿方式による空調給気清浄度の評価

次世代都市型病院の室内環境・エネルギー性能の検証・評価研究 （第17報）エネルギーマネジメントの取り組みと水・エネルギー消費量の分析・評価

次世代都市型病院の室内環境・エネルギー性能の検証・評価研究 （第17報）エネルギーマネジメントの取り組みと水・エネルギー消費量の分析・評価

次世代都市型病院の室内環境・エネルギー性能の検証・評価研究 （第14報）外気処理システムの検証と送水温度変更運用に関する評価

次世代都市型病院の室内環境・エネルギー性能の検証・評価研究 （第14報）外気処理システムの検証と送水温度変更運用に関する評価

次世代都市型病院の室内環境・エネルギー性能の検証・評価研究 （第16報）地中熱利用ヒートポンプシステムのシミュレーションモデル性能向上に関する検証

次世代都市型病院の室内環境・エネルギー性能の検証・評価研究 （第16報）地中熱利用ヒートポンプシステムのシミュレーションモデル性能向上に関する検証

The energy and indoor environmental performance of Egyptian offices: Parameter analysis and future policy

Buildings are a significant contributor to the rapidly increasing electricity demand in Egypt which is straining the existing supply network causing economic and social impacts. There are current initiatives aimed at improved building performance including adoption of international standards. The performance of existing Egyptian buildings is not well understood making the impact of these international standards uncertain. This paper provides insight into performance of current Egyptian office buildings through a multi-building energy survey and a detailed case study. The most common office type in the survey has natural ventilation and local cooling. A process to capture observed performance in a representative model and input parameter set is presented. The model is used to investigate performance impacts of parameters including: location, weather, building envelope, intensity of occupancy, behaviour, and installed systems including the HVAC strategy. HVAC strategy was identified as the most significant factor. Typical Egyptian offices with natural ventilation and local cooling systems under personal control have electricity demand less than 50% of centrally serviced buildings. System efficiencies (HVAC, lights, equipment) and occupant behaviour (e.g. use of systems, temperatures) were also identified as significant factors, each with potential of around 30% saving compared to current typical offices. Possible policy measures to promote energy efficient systems and energy conscious behaviour are proposed which together can reduce the energy demand of typical offices by 50%. Trade-offs between energy use and indoor environmental quality (IEQ) are discussed.

Ventilation and energy performance of partitioned indoor spaces under mixing and displacement ventilation

Large variation in indoor air quality (IAQ) and thermal comfort can occur in partitioned office spaces due to heterogeneous air mixing. However, few published studies examined IAQ, thermal comfort, and energy performance of partitioned occupied spaces, which are commonly found in today’s buildings. The objective of this study is to evaluate indoor environmental quality and air conditioning performance of a partitioned room under two typical ventilation modes: (1) mixing ventilation and (2) displacement ventilation. For a total of six representative air-conditioning scenarios, three-dimensional computational fluid dynamics (CFD) simulations are performed to examine temperature distribution, ventilation effectiveness, energy consumption, and local thermal comfort for two partitioned spaces. Simulation results indicate that temperature distribution in a partitioned room is a strong function of ventilation strategy (mixing vs. displacement), but marginally affected by diffuser arrangements. Local age-of-air (air freshness) significantly varies with both diffuser arrangement and ventilation strategy. Regarding energy consumption, displacement ventilation can achieve an indoor set-point temperature in the partitioned spaces about two times faster than mixing ventilation. Under mixing ventilation, the time to achieve a set-point temperature was notably reduced when each partitioned space is served by its own diffuser. For the same supply airflow rate, displacement ventilation can generate local draft risk at ankle level, while mixing ventilation may result in a draft sensation in wider areas around an occupant. Overall, the results suggest that mixing ventilation system can save energy if each partitioned zone is served by its own diffuser such as a multi-split air conditioning. However, when multiple partitioned zones are served by only one diffuser, displacement ventilation is more energy-efficient and can achieve higher ventilation effectiveness than mixing ventilation.