Sustainable Cities and Society 13(2014)57–68
Contents lists available at ScienceDirect
Sustainable Cities and
Society
j o u r n a l h o m e p a g e :w w w.e l s e v i e r.c o m /l o c a t e /s c
s
增肥方法Monitoring building energy consumption,thermal performance,and indoor air quality in a cold climate region
Tanzia Sharmin a ,Mustafa Gül a ,∗,Xinming Li a ,Velin Ganev b ,Ioanis Nikolaidis b ,Mohamed Al-Husin a
a Department of Civil and Environmental Engineering,University of Alberta,9105116th Street,Edmonton,Alberta,Canada b
Department of Computing Science,2-21Athabasca Hall,University of Alberta,Edmonton,Alberta,Canada
朝思暮想的意思
a r t i c l e
i n f o
Keywords:
Sensor-bad monitoring system Energy usage
Building envelope thermal performance Indoor air quality
Building management system
支持的英语
a b s t r a c t
Buildings are major consumers of the world’s energy.Optimizing energy consumption of buildings during operation can significantly reduce their impact on the global environment.Monitoring the energy usage and performance is expected to aid in reducing the energy consumption of occupants.
In this regard,this paper describes a framework for nsor-bad monitoring of energy performance of buildings under occupancy.Different types of nsors are installed at different locations in 12apartment units in a building in Fort McMurray,Alberta,Canada to asss occupant energy usage,thermal performance of the building envelope,and indoor air quality (IAQ).The relationship between heating energy consumption and the thermal performance of building envelope and occupant comfort level is investigated by analyzing the monitoring data.The results show that the extent of heat loss,occupant comfort level,and appliance usage patterns have significant impacts on heating energy and electricity consumption.This study also identifies the factors influencing the poor IAQ obrved in some ca-study units.In the long term,it is expected that the extracted information acquired from the monitoring system can be ud to support intelligent decisions to save energy,and can be implemented by the building management system to achieve financial,environmental,and health benefits.
©2014Elvier Ltd.All rights rerved.
1.Introduction
The building ctor accounts for about 30%of total green-hou gas (GHG)emissions in Canada (N
RC,2006).Furthermore,the construction and operation of buildings are responsible for over a third of the world’s energy consumption (Straube,2006).Data shows that energy consumption and GHG emissions in build-ing ctor are growing at an advanced rate than in other ctors (Akashi &Hanaoka,2012).As a result,reducing energy consump-tion has become esntial to planning,construction,and u of buildings from the environmental point of view (Stoy,Pollalis,&Fiala,2009).This also entails that the building ctor has con-siderable potential for energy and energy-related CO 2emissions
savings (Gökc
¸e &Gökc ¸e,2013).According to the International Energy Agency,the building ctor can reduce energy consump-tion with an estimated energy savings of 1509Mtoe (million tonnes of oil equivalent)by 2050.Furthermore,through energy-efficient building design,carbon dioxide (CO 2)emissions can be reduced,
∗Corresponding author.Tel.:+17804923002.
E-mail address:mustafa.gul@ualberta.ca (M.Gül).
which can possibly mitigate 12.6Gt (gigatonnes)of CO 2emissions by 2050(International Energy Agency,2010).
Energy consumption by built environments can be reduced through new designs,technologies,and materials;proper control;and the u of effective energy management systems by consider-ing factors such as building orientation,shape,wall–window ratio,insulation,u of high-efficiency windows,and natural ventila-tion (Dawood,Crosbie,Dawood,&Lord,2013).However,electrical loads,especially miscellaneous electrical loads (involving a range of products,devices,and electrical equipment in some combina-tion,common in every houhold)consume a significant portion of total building energy (Hendron &Eastment,2006).In Canada,the residential building ctor consumes approximately 16%of total condary energy usage (NRC,2006).According to Statistics Canada,in 2007the average Canadian houhold consumed 106GJ (gigajoules)of energy,with the national total reaching 1,368,955TJ (terajoules)(Statistics Canada,2007).A substantial share of total energy consumption is due to improper u of appliances,and elim-inating this wastage can reduce the overall energy consumption by approximately 30%in buildings (US DOE Energy Information Administration,2003).Today it is important to focus on greater energy efficiency to reduce our impact on the environment by
dx.doi/10.1016/j.scs.2014.04.009
2210-6707/©2014Elvier Ltd.All rights rerved.
58T.Sharmin et al./Sustainable Cities and Society13(2014)57–68
氨水的密度reducing fossil fuel consumption(Gua,Sun,&Wennersten,2013; Sharmin,Li,Gökc¸e,Gül,&Al-Husin,2012).
Built environments also have a significant impact on human health.The extent of a building’s impact on human health and the environment depends on the building design,materials,and the methods ud for construction and operation(Vittori,2002). According to the Science Advisory Board of the United States Envi-ronmental Protection Agency(EPA),indoor environment stands among the topfive environmental risks to public health.In Canada, people spend an average of89%of their time indoors and66%of their time indoors at home(Leech,Wilby,McMullen,&Laporte, 1996),and there is a possibility that people with weak immune systems may suffer from asthmatic symptoms or other respiratory health problems as a result of exposure to poor indoor air quality (Vittori,2002).Considering the fact that human health is affected by poor indoor air quality(IAQ),it is important to maintain a healthy IAQ in the interest of occupant health.Continuous monitoring of indoo
r environmental quality(IEQ)can thus play a significant role in maintaining healthy indoor environments.
A significant aspect of asssing the sustainability of a building is the monitoring of energy performance(Berardi,2012).Recent innovations in nsing,data logging,and computing technologies have improved monitoring of indoor environment and energy per-formance of buildings.“Real-time”energy performance and IEQ monitoring are significant from the perspective of real-time feed-back to promote energy-saving behavior,and also for maintaining healthy IAQ.Proper targeting and monitoring of energy consump-tion and continuous energy management can be effective strategies for improved energy performance of buildings,and can result in reductions in operating costs of facilities(Lee&Augenbroe,2007; Sapri&Muhammad,2010).Rearch studies examining the effect of energy feedback information on occupant behavior have shown that real-time feedback can be a powerful impetus for behavioral change.McClelland and Cook(1980)first tested the impact of con-tinuous energy feedback on electricity usage.The results showed that on average electricity usage was lowered by12%in the homes with continuous electricity usage feedback compared to the homes with no usage feedback system(as cited in Allen&Janda,2006). In another study,a technical rearch university has monitored energy usage to reduce energy costs through an energy awareness progra
m that offered departments a chance to receive payments of up to30%of the savings achieved.The departments had accom-plished energy savings(saving about$300,000per year)after one and half years of monitoring through improved operations and maintenance procedures and reduced their usage from about44 million kWh to40million kWh(Energy Star,2002).Hutton,Maur, Filiatrault,and Antola(1986)have shown how the feedback pro-vided by monitoring helped to conrve energy for over75%of the subjects in25houholds in three cities.In a ca regarding water usage,the city of Boston,MA,USA was unable to account for the u of50%of the water ud in its municipal water system and,after installing meters,water that was unaccounted for had dropped to 36%(Grisham&Fleming,1989).Another study has shown that an effective energy management system can identify problems in an operating system which might not otherwi have been identified (Mills&Mathew,2009).Yang and Wang(2013)has shown that energy management systems can also provide comfortable building environments with high energy efficiency.
Literature reviews from the last ten years show that usage of energy can be reduced from0%to20%by using a variety of feed-back mechanisms(Abraham,Steg,Vlek,&Rothengatter,2005). However,despite the fact that providing appropriate feedback can significantly reduce the overall energy consumption,relying only on occupa
nts’awareness and behavioral change might not be an effective approach.In a recent study,wireless AC plug-load meters and light nsors were deployed in a computer science laboratory as a ca study in energy monitoring.The study reported that more than30%energy savings were achieved immediately after installing a monitoring system,but that the savings were sub-quently reduced to less than4%of the week one level by the fourth week of the study.It light of this ca,it might be considered that an effective solution for reducing energy consumption could be an automated energy management system,in addition to ur coop-eration(Jiang,Van Ly,Taneja,Dutta,&Culler,2009).
Major progress has been made in recent years in accomplish-ing greater awareness(Jiang et al.,2009),showing that advanced measurement of energy usage enables reduction of energy con-sumption.While the approach of monitoring energy usage is uful to achievefinancial benefits,a holistic monitoring of the perfor-mance of the building system can also be ud to identify the factors influencing irregular energy usage or non-standard IEQ.Any information pertaining to irregularity of building system perfor-mance can contribute to building management systems intended to support operational improvement,and can also provide the infor-mation needed to encourage behavioral and operational changes by building occupants and operators.Monitoring is esntial to achieving an ene
rgy-efficient building management system,but nsor-bad monitoring is sometimes costly.In recent years more cost-effective high performance nsor technologies have been introduced,such that the benefits of utilizing this technology outweigh the associated costs.Continuous collection of the indi-vidualized energy u information would translate into incread energy u awareness,identification of problems in the building management system,and notification of irregular energy usage and non-standard indoor environmental parameters,all of which can lead to more sustainable building operations.However,it remains an open question whether the apparent additional understanding would be enough to justify the cost of installation,maintenance, and calibration of nsors.This paper thus offers a methodological approach by which to extract uful information by establishing relationships and studying patterns across different components of a building management system,facilitated by the installation of various nsors in a ca study,the“Stony Mountain Plaza”project in Fort McMurray,Alberta,Canada.
1.1.Objective and scope
The objective of the nsor-bad monitoring system adopted in this rearch is to provide relevant information regarding effec-tive management of building systems in cold-climate regions.The implemented monitoring system can be ud for increasing energy performance and occupant comf
ort while reducing energy and water consumption.In this study,the ASHRAE standard specifying environmental parameter ranges(indoor air temperature,RH,CO2 level)has been ud to define occupant comfort.A holistic exam-ination of the performance of the building system(energy usage, thermal performance,and IEQ)helps to determine whether or not the system is working efficiently by identifying correlations across different monitoring components.A more advanced understand-ing of the recorded data is expected to result in changes in building operations through the u of intelligent controls that automati-cally adjust to environmental requirements.It is expected that the extracted information and strategies acquired from the monitor-ing system can be implemented within the building management system to achievefinancial,environmental,and health benefits. 2.Methodological approach
In order to conduct a holistic examination of the performance of the building system under consideration,operating energy usage (e.g.,electrical energy usage,space heating energy usage,and
T.Sharmin et al./Sustainable Cities and Society13(2014)57–68
59
Fig.1.Objective and methodological approach.
houhold water usage);thermal performance of the building; and IAQ under occupancy are monitored.Twelve sample units are chon in the building to be monitored for energy performance. Different types of nsors are installed in the individual units in order to monitor different components.Finally,recorded data are analyzed in order to extract uful information.Fig.1shows the objective and the monitored components for building energy performance under occupancy.
2.1.Sample ca-study unit
Two four-storey residential buildings have been constructed as part of the“Stony Mountain Plaza”project in Fort McMurray, Alberta,Canada.Both buildings are oriented with their longer axis facing north and south.Building1has70units while building2has 55units.There are two types of units in building1:one-bedroom and two-bedroom units.For monitoring building energy perfor-mance,three ca-study units in eachfloor of building1with the same relativefloor plan position are lected:(1)Type‘A’unit (one-bedroom)facing north,(2)Type‘A’unit(one-bedroom)facing south,and(3)Type‘B’unit(two-bedroom)facing south.The sam-ple houholds are assigned code numbers1–12,and the specific locations of the units in theirfloors are not revealed for the sake of privacy.Fig.2displays the12ca-study units.
咖啡厅效果图2.2.Types and locations of installed nsors
Different types of nsors are ud for different types of required information in this asssment of building energy performance under occupancy.For electrical energy usage,Brultech ECM-1240 power meters are ud.Each apartment receives power from two phas(phas A and B).Two power meters,one for each pha, recording the total energy for each load(in Ws)are therefore installed in each ca-study unit.One Kamstrup MULTICAL601 heating meter is ud for monitoring the energy from the water circulation heating system.Three nsors are also ud for this purpo:o
neflow meter and two temperature probes(for supply temperature,T s,and return temperature,T r).The heating meter records the total volume(L),total mass(g),currentflow(L/s),cur-rent T s and T r(◦C),and total energy(Wh).The energy consumed by the water circulation heating system can be calculated satisfying Eq.(1).
反坐E=V(T s−T r)k(1) where V:volume;T s:supply temperature;T r:return temperature; k:thermal coefficient.
For monitoring houhold water usage,Minomess130water meters are ud.There are two water meters in each apartment, one monitoring total incoming water and one monitoring output (cumulative hot water usage in the apartment)of the hot water tank.Two heatflux nsors(HFT3Soil Heat Flux Plate)are ud for monitoring thermal performance of the building envelope:one measuring the heatflux(W/m2)through the studs and the other measuring the heatflux through the insulation.The nsor ud for IAQ measurement is the IAQ Point air monitoring device man-ufactured by Honeywell Analytics.This device records real-time values of CO2(ppm),RH(%),and temperature(◦C)(Sharmin et al., 2012).The locations of the nsors for one-bedroom units and two-bedroom units are as shown in Fig.3.
2.3.Development of system architecture
The power consumption meters(Brultech ECM-1240)commu-nicate using ZigBee with four EtherBee gateways(one on each floor),which are connected by a CAT5Ethernet cable to a single-board computer through a5-port switch.The energy meter and
the Fig.2.Ca-study building and lection of ca-study units.
60
T.Sharmin et al./Sustainable Cities and Society 13(2014)
57–68
Fig.3.Location of nsors in ca-study units.
IAQ nsor u the LonTalk protocol to communicate with an iLON smart rver,which is also connected to the single-board computer where the data are being encrypted and transmitted to a databa rver through a cured connection over the Internet.The heat flux nsors are connected to the CR1000data logger (Campbell Scientific,Inc.)through a Solid State Multiplexer (Campbell Scien-tific,Inc.),which makes it possible to connect all 24of the heat flux nsors to a single data logger.The data logger converts the ana-log signal from the heat flux nsors into digital values and nds the values to the SBC through an Ethernet interface (Sharmin
et al.,2012).Fig.4provides a flowchart of the data collection system adopted in this project.
3.Data analysis
This ction discuss findings bad on the collected data to asss building energy performance under occupancy.The data ts ud for the analysis prented in this paper have been collected during regular operation of the
building.
Fig.4.System architecture for data collection.
T.Sharmin et al./Sustainable Cities and Society13(2014)57–68
61
Fig.5.Data analysis framework for electrical energy consumption.
3.1.Measurement of electrical energy usage
According to Statistics Canada(2007),Alberta’s average per houhold u of electricity in2007was the lowest among all provinces(26GJ).A possible reason for this low electricity con-sumption might be the comparably high rate of natural gas consumption in Alberta due to the low price of natural gas.In this paper,26GJ is t as the annual per houhold usage threshold. We consider the electricity consumption for individual appliances and the total electricity consumption for the ca-study units. By measuring the electricity consumption of occupants,building management can pursue appropriate ,tting an opti-mum usage limit)if the electricity usage continuously exceeds the threshold of electricity usage established.
Fig.5shows the data analysis framework for electrical energy consumption,while Fig.6shows the total electricity consump-tion by ca-study unit(except unit8,becau of missing data). It is obrved in Fig.6that the electricity consumption by units7 (Type A)and9(Type A)in2012exceeds the26GJ threshold.Even though units7and9are type A(one-bedroom)units,the electric-ity consumption of the units is higher than the other ca-study units.
The data analysis framework(Fig.5)adopted in this study identi-fies factors that influence higher elect
ricity consumption by a given unit by comparing the electricity consumption of different appli-ances of the lected unit with the average electricity consumption of individual appliances of all the ca-study units.Fig.7prents the influencing factors for higher electricity consumption of3ca-study units(units7,9and10).The three units are chon as examples since two of them(units7and9)exceed the26-GJ thresh-old and the other unit(unit10)has comparatively higher electricity usage but appears to be influenced by different factors than units7 and9.Our data analysis shows that the primary factors influencing the higher electricity consumption in unit7are the bedroom appli-ances,electrical duct heating,kitchen plug,and kitchen-bathroom lighting,since electricity consumption by the appliances in unit 7is much higher than the average of the11ca-study units for the appliances.A possible reason for higher electricity consump-tion in the bedroom of unit7may be the u of electrical heating radiators by occupants.On the other hand,bedroom appliances and oven usage for unit9and hot water tank and refrigerator usage for unit10are identified as the primary influencing factors accounting for the higher electricity consumption of the respective units.
It is worth noting that houhold energy u can vary bad on a number of factors,including the number of occupants,lifestyle, and usage of different appliances.With the continuous monitor-ing of e
lectrical energy consumption,it is possible to identify the influencing factors of higher electricity consumption of occupants and to t an optimum value for electrical energy usage accord-ingly.Bad on the monitoring of electricity usage carried out in this study,building management can t an appropriate optimum range of yearly energy usage by occupants.
3.2.Measuring thermal performance of building envelope and space heating energy usage
那个清晨For this rearch,the heatflux—the rate of heat energy transfer—through studs and insulation is also monitored.Since studs(working as thermal bridges between outdoor and indoor environments)lo more heat than does insulation,this rearch measures heatflux through studs and insulation parately.In order to asss the impact of orientation on heatflux for the ca-study units,annual average heatflux through studs and annual average heatflux through insulation are compared for north-facing and south-facing units.At eachfloor level,one north-facing unit and one south-facing type A(one-bedroom)unit are lected in order to compare heatflux.As expected,the collected data in Fig.8shows that north-facing units have greater heat loss than south-facing units when considering the2nd and3rdfloor.However,contrary to expectations,at the ground(stud)and topfloor,south-facing units have greater heat loss than north-facing units.The recorded data in Fig.8gives an inconclusive result.In order to identify long-term patterns(if any)of heatflux for different orientations,it is impor-tant
to monitor the data for a few years.If patterns of heatflux for differentfloor levels(variations with respect to height)or differ-ent orientations are identified,,incread
汉堡面包
insulation) Fig.6.Electricity consumption for ca-study units.
