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Evaluation of energy performance of LEED building (Friedman) at UBC : technical report Logawa, Banda; Kourkoulis, Ioannis Jun 2, 2014

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 UBC Social Ecological Economic Development Studies (SEEDS) Student ReportBanda Logawa, Ioannis KourkoulisEvaluation of Energy Performance of LEEDBuilding (Friedman) at UBCAPSC 598GJune 02, 201410631663University of British Columbia Disclaimer: “UBC SEEDS provides students with the opportunity to share the findings of their studies, as well as their opinions, conclusions and recommendations with the UBC community. The reader should bear in mind that this is a student project/report and is not an official document of UBC. Furthermore readers should bear in mind that these reports may not reflect the current status of activities at UBC. We urge you to contact the research persons mentioned in a report or the SEEDS Coordinator about the current status of the subject matter of a project/report”.    ---Technical Report---  Evaluation of Energy Performance of LEED Building (Friedman) at UBC  Banda Logawa and Ioannis Kourkoulis    Acoustics and Noise Research Group University of British Columbia   --June 2nd 2013---              i  Abstract  Recent studies conducted by New Building s Institute have shown that there were gaps between modeled and actual performance of numerous LEED Buildings. This study was conducted to investigate this phenomenon in one of LEED Buildings in University of British Columbia, try to identify possible sources of discrepancies, and establish guidelines to repeat similar investigations on other buildings. Based on the recommendations of the project client, Friedman Building was chosen in the study. To achieve the project objectives, several efforts were made such as analyzing annual and monthly energy consumption data, comparing LEED drawings and as - built drawings, comparing the occupancy pattern in the building, and conducting interviews with the program administrators. There were several sources of discrepancies identified in the study: changes in energy demand throughout the year, changes in design before and after submission of LEED Application, inaccurate plug load assumptions, and building envelope degradation.       ii  Acknowledgement  We would like to express our gratitude to our project supervisor, Dr. Murray Hodgson, and our teaching assistant, Nima Khalkali, for providing us valuable feedbacks throughout the term. We also want to thank our project clients from UBC Campus + Community Planning for their support during the project: Lilian Zaremba, Bud Fraser, and Penny Martyn.   In ad dition, it wouldn͛t be possible to successfully complete this project without the supports of Deb Capps, Green Zone Facility Manager; Larry S mithe and Liam Mulrooney from Division of Physical Therapy of the School of Rehabilitation Sciences; and Clint Meyers from School of Audiology and Speech Sciences. We want to thank them for giving us numerous helps during our audit process in Friedman Building. Lastly, we would also li ke to thank fellow SBSP members, Mahdi Salehi, Belgin Terim Cavka, and Stefan Storey for sharing their resources with us and their involvement during numerous discussions on the project.    iii  Table of Contents Abstract  .......................................................................................................................................................... i Acknowledgement  ........................................................................................................................................ ii Table of Contents ......................................................................................................................................... iii List of Ta bles ................................................................................................................................................. v List of Figures  ............................................................................................................................................... vi 1.  Introduction  .......................................................................................................................................... 1  2.  Research Methodologies  ...................................................................................................................... 1  3.  Background Information  ....................................................................................................................... 2  a. Previous Study ................................................................................................................................... 2  b. Renovation of Friedman Building ..................................................................................................... 5  c. LEED Accreditation  ............................................................................................................................ 8  d. Weather Normalization Technique  ................................................................................................. 11  e. Vancouver Climate Condition  ......................................................................................................... 12  i. Temperatures .............................................................................................................................. 13  ii. Daylight ....................................................................................................................................... 14  4.  Energy Perfor mance Analysis .............................................................................................................. 15  a. Modelled and Measured Energy Performance  ............................................................................... 15  b. Monthly and Daily Energy Demand Trend  ...................................................................................... 17  c. Weather Normalization of Energy Consumption for UBC Friedman Building  ................................ 29  5.  Potential Sources of Discrepancies  ..................................................................................................... 34  a. Changes in Energy Demand Throughout the year .......................................................................... 34  i. Weather Contribution ................................................................................................................. 34  ii. Installation of New Equipment  ................................................................................................... 34  iii. Changes in Occupancy Pattern  ................................................................................................... 34  b. Changes in Design before and after LEED Application .................................................................... 40  c. Inaccurate Building Plug Load Assumption  ..................................................................................... 41  d. Building Envelope Degradation ....................................................................................................... 41  6.  Conclusions and Recommendations ................................................................................................... 42  7.  References .......................................................................................................................................... 43  8.  Appendix  ............................................................................................................................................. 44  a. Modelling Par ameters ..................................................................................................................... 44    iv  b. Drawings ......................................................................................................................................... 49  i. LEED Package  .............................................................................................................................. 49  ii. As -  Built Drawings ....................................................................................................................... 50  c. Site Visit Results and Photos  ........................................................................................................... 51  i. Division of Physica l Therapy, School of Rehabilitation Sciences ................................................ 51  ii. School of Audiology and Speech Sciences  .................................................................................. 51       v  List of Tables Table 1. Electrical and Gas Consumption Distribution before Renovation  .................................................. 7  Table 2. Energy & Atmosphere Points Breakdown  ....................................................................................... 8  Table 3. Points Requirements for LEED NC 1.0 and LEED NC 2009  .............................................................. 9  Table 4. Energy & Atmosphere Category in LEED NC 1 .0 and LEED NC 2009  ............................................... 9  Table 5. Optimized Energy Performance Criterion for LEED NC 1.0  ........................................................... 10  Table 6. Optimized Energy Performance Criterion for LEED NC 2009  ........................................................ 10  Table 7. Energy Consumption Comparison  ................................................................................................. 16  Table 8. Heating degree days over the last 25 years (annual data) for Vancouver  .................................... 30  Table 9. Weather normalization of energy consumption  ........................................................................... 31  Table 10. New Single - Duct VAV Terminal Units indicated in As Built Drawings compared to LEED Drawings ..................................................................................................................................................... 40  Table 11. New Air Handling Unit indicated in As Built Drawings compared to LEED Drawings  ................. 40      vi  List of Figures Figure 1. LEED - NC Certifications by Ye ar ...................................................................................................... 2  Figure 2. Distribution of Energy Star Rating  .................................................................................................. 4  Figure 3. Measured versus Design EUIs  ........................................................................................................ 4  Figure 4. Measured vs Proposed Savings Percentage  .................................................................................. 5  Figure 5. Simulated Electrical Consumption before Simulation  ................................................................... 6  Figure 6. Simulated Steam Consumption before R enovation ...................................................................... 6  Figure 7. LEED credit breakdown for Friedman Building  .............................................................................. 8  Figure 8. Averages solar irradiation of Vancouver compared to Miami  ..................................................... 12  Figure 9. Average temperature of Vancouver  ............................................................................................ 13  Figure 10. Daylight in Vancouver  ................................................................................................................ 14  Figure 11. Predicted Energy Performance  .................................................................................................. 15  Figure 12. Annual Energy Consumption of Friedman Building based on the Meter Data  ......................... 16  Figure 13. Annual Energy Consumption of Friedman Building, Taking Energy Conversion Ration from Natural Gas to Steam into Consideration  ................................................................................................... 17  Figure 14. Electrical Demand in Year 2010  ................................................................................................. 18  Figure 15. Steam Demand in Year 2010  ...................................................................................................... 18  Figure 16. Electrical Demand in Year 2011  ................................................................................................. 19  Figure 17. Steam Demand in Year 2011  ...................................................................................................... 19  Figure 18. Electrical Demand in Year 2012  ................................................................................................. 20  Figure 19. Steam Demand in Year 2012  ...................................................................................................... 20  Figure 20. Electrical Demand in Year 2013  ................................................................................................. 21  Figure 21. Steam Demand in Year 2013  ...................................................................................................... 21  Figure 22. Electricity Demand Distribution for Year 2013  .......................................................................... 22  Figure 23. Steam Demand Distribution f or Year 2013  ................................................................................ 23  Figure 24. Electricity Demand Distribution 2012  ........................................................................................ 23  Figure 25. Steam Demand Distribution 2012  .............................................................................................. 24  Figure 26. Electrici ty Demand Distribution 2011  ........................................................................................ 24  Figure 27. Steam Demand Distribution 2011  .............................................................................................. 25  Figure 28. Electricity Demand Distribution 2010  ........................................................................................ 25  Figure 29. Steam Demand Distribution 2010  .............................................................................................. 26  Figure 30. Daily Electricity Consumption on the First Wednesday in August  ............................................. 27  Figure 31. Outdoor Air Temperature on the First Wednesday in August  ................................................... 27  Figure 32. Daily Steam Demand on the First Wednesday in December  ..................................................... 28  Figure 33. Outdoor Air Temperature on the First Wednesday in December  ............................................. 28  Figure 34. Heating d egree days over the last 25 years (annual data) for Vancouver ................................. 31  Figure 35. Heating degree days over the last 5 years (quarterly data) for Vancouver  ............................... 32  Figure 36. Normalized Natural gas consumption for years 2010, 2011, 2012 and 2013  ........................... 32  Figure 37. Differences between Normalized and Actual Natural Gas Consumption for Years 2010, 2011, 2012 and 2013  ............................................................................................................................................ 33  Figure 38. Occupancy Pattern for Room 204 - Feb 2013  .............................................................................. 35    vii  Figure 39. Occupancy Pattern for Room 204 -  Aug 2013  ............................................................................ 36  Figure 40. Occupancy Pattern for R oom 204 -  Dec 2013  ............................................................................. 36  Figure 41. Occupancy Pattern for Room 304 -  Feb 2013  ............................................................................. 37  Figure 42. Occupancy Pattern for Room 304 -  Aug 2013  ............................................................................ 37  Figure 43. Occupancy Pattern for Room 304 -  Dec 201 3  ............................................................................. 38  Figure 44. Occupancy Pattern for Room 354 -  Feb 2013  ............................................................................. 38  Figure 45.Occupancy Pattern for Room 355  ............................................................................................... 3 9  Figure 47. ASHRAE 90.1 Guideline for Occupancy Density, Receptacle Density, and Service Hot Water Quantities.  ................................................................................................................................................... 41     1   1. Introduction While LEED accreditation is often used to evaluate the performance of green buildings, there are some evidences which show performance gap between modelled expectations and actual performances of many LEED Buildings.  In 2008, New Building s Institute studied 121 different LEED buildings and summarize d their findings in a report written for US Green Building Council. Across the buildings studied by NBI, there was a wide scattering of data observed. While some buildings did much better than anticipated, almost the same number of buildings performed worse or even much worse [ 1 ] . This study was conducted to follow up EB/͛s study and investigated sources of discrepancies which might result in the performance gap between the modelled and actual building performance. Due to the time limitation, this study only focused on one LEED building  in UBC, Friedman Building. The results from Friedman building would then be used as a foundation for future studies on other UBC buildings. To accomplish this research objective several efforts have been made by the authors such as evaluating mechanical, electrical, and architectural drawings of the building, conducting site visit to check the consistency between the design and actual implementation, conducting interviews with the program administrators, and analyzing  electrical and steam consumption of the building.  2. Research Methodologies This study was mainly conducted to provide insights to the performance gap issues which were often encountered in LEED buildings. Furthermore, it would also use  the results from Friedman building to develop guidelines for future investigation on other LEED buildings in UBC. To achieve these objectives, the following methods were pursued in the study:  1.  Reviewed background information on the renovation project of Fr iedman building 2.  Analyze d annual and monthly energy consumption data 3.  Reviewed weather normalization technique  4.  Reviewed any changes in drawings since LEED application has been submitted  5.  Conducted site visit to compare the actual equipment used in the buildin g with the drawings 6.  Conducted interview with program administrators of both Department of Physical Therapy and School of Audiology and Speech Sciences  7.  Analyze d the occupancy pattern for classrooms in the building 8.  Provided recommendations for future studies  on other UBC buildings    2   3. Background Information  a. Previous Study Numerous  certified LEED NC  buildings (121 buildings) in 2008 were studied by New Building s Institute (NBI) to provide information with regards to the link between design intention and outcome for LEED projects. In a report prepared for US Green Building Council (USGBC) , NBI showed that there were large variations in performances between these buildings. While some buildings performed better than intended, similar number of buildings performed worse or even much worse [ 1 ] . To provide meaningful data, NBI has included buildings with all type of LEED certifications in the study. Distributions of the buildings based on the certification types and year of certification can be seen in the figures below.  Figure 1. LEED-NC Certifications by Year [1] In the study, t hree different metrics were utilized to analyze the energy performance of the building: Energy Use Intensity (EUI) comparison between LEED and national building stock, Energy Star Rating of the LEED buildings, and  the measured performance results compared to initial design and baseline modelling. As seen in the fi gure below, EUI of the buildings were compared to the data from Commercial Building Energy Consumption Survey (CBECS). For all LEED building analyzed in the study  excluding 21 high energy type building s, the median measured EUI was approximately 69 kBtu/sf  or 24% better than the CBECS national average. Furthermore, LEED EUIs average for offices, the most common building type, was 33% better than CBECS.     3   As mentioned previously, 21 high energy buildings were considered separately in the study. The EUI of the se buildings reached up to nearly 700 kBtu/sf with the median of 238 kBtu/sf.    Figure 2. EUI Distributions across buildings [1] Unlike the first metric, Energy Star program which was proposed by U.S. Environmental Protection Agency (EPA) rated a building͛s energy use in relation to edžisting building stocŬ for the same activity category. Based on the study, average Energy Star rating of LEED building s was 68 which indicated that it was better than 68% of similar buildings. Even though this result showed favourable results, there were approximately one quarter of the buildings with rating below ϱϬ, “meaning they used more energy than average comparable existing building stock  [ 1 ] .” The distribution of Energy Star Rating could be seen below.   4    Figure 2. Distribution of Energy Star Rating [1] In addition to the two metrics above, the third metric that was used in the study compared the measured energy performances to the modelled code baseline building which was determined using the Energy Cost Budget (ECB) and performance requirements in ASHRAE 90.1.  In comparing the m easured and design EUIs of the buildings, NBI has found significant amount of variations between individual building results. As seen in the figure below, n umbers of building which were doing worse than predicted were approximately similar to the ones which were doing better.  Figure 3. Measured versus Design EUIs [1]   5   The measured and proposed savings of the buildings also showed significant amount of variation with several buildings utilized more energy than the code baseline. This comparison could be seen in the figure below.  Figure 4. Measured vs Proposed Savings Percentage [1] There were several sources of variations mentioned in the study such as differences in operational practices and schedules, equipment, construction changes, and others issues not anticipate d in energy modelling process.  b. Renovation of Friedman Building  O riginally built in 1959, Friedman building was the place for the Department of Anatomy  which had multiple energy-  intensive laboratories. As part of the UBC Renew program , Friedman building were renovated in ϮϬϬϴ to “improve life safety, accessibility, energy efficiency, and opportunities for student/ faculty interaction [ 2 ] .” &urthermore, it would instead house the School of Audiology and Speech Sciences and Physical Therapy Division of the School of Rehabilitation Sciences.  Because of the change in occupants and their energy demand, this renovation was sufficient to upgrade the LEED certification of the building from Silver to Gold.  The renovation of Friedman building was considered as a major renovation. Because of this, it was categorized under LEED New Construction (NC) certification. To understand the scale of the renovation,   6   the authors have studied previous report written by MCW Consultants Ltd.  who was responsible for analyzing the performance of the building b efore and after the renovation.  Due to the lack of measurement system  before the renovation, building energy performance were simulated by M CW using eQuest  software. The simulated performance of the building before renovations was as followed.  Figure 5. Simulated Electrical Consumption before Simulation [2]  Figure 6. Simulated Steam Consumption before Renovation [2]   7   Table 1. Electrical and Gas Consumption Distribution before Renovation [2]  As seen in the table above, total electrical consumption of the building before renovation was approximately 1,074,400 kWh or 3,867,840 MJ. The total natural gas consumption was approximately 10,460,000,000 Btu or 11,0 35,890 MJ , while miscellaneous excluded equipment accounted for 41,100 kWh or 147,960 MJ (not shown in the table). Under the assumption that the conditioned floor area was approximately 5,235 m 2  [ 2 ] , energy unit intensity (EUI) of the building was about 2,810 MJ/m 2  or 247.48 kBtu/sf. Comparing this value to the buildings studied by NBI, the original Friedman building would be comparable to the excluded high energy type building which has the median EU I value of 238 kBtu/sf.  On the other hand, t he modelled energy performance of the renovated building was significantly less. It was estimated to be 1,118,044 MJ for electricity and 2,958,529 MJ for natural gas. Therefore, total EUI of the renovated building was approximatel y 181.8 kWh/m 2  or 57.59 kBtu/sf. This value  was less than 25% of the original consumption value.  The detail of this prediction model would be discussed further in A ppendix A.       8   c. LEED Accreditation As mentioned in the previous section, the  renovation was intended to upgrade the LEED certification  of Friedman Building from Silver to Gold. There were total of 7 credits awarded in the Energy & Atmosphere category  (5 credits for optimized energy performance, 1 point for ozone protection, and 1 point for green power). The breakdown of the LEED credits for the  renovated Friedman building could be seen in the figure below.   Figure 7. LEED credit breakdown for Friedman Building [3]  Table 2. Energy & Atmosphere Points Breakdown Categories Description Points Optimize Energy Performance 3 4% energy reduction compared to MNECB  5  Ozone Protection HVAC system free of HCFCs  1  Green Power 1 00 % electricity from green power  1    9   As seen in the table above, most of the points in the Energy& A tmosphere category were achieved through optimizing the energy performance of the building. It should be noted that these points and LEED certification were awarded based on LEED NC 1.0 guideline. For buildings built after 2009, LEED NC 2009 should be foll owed instead.  There are some differences between the two versions of LEED NC. One of the most notable revisions in LEED NC 2009 is the overall increase of available points. Thus, increases the point requirements for each certification levels. Furthermore, in the Energy and Atmosphere category, more emphasis has been given to renewable energy as well as measurement and verification criteria. Differences in the two guidelines could be briefly summarized in the following tables. Table 3. Points Requirements for LEED NC 1.0 and LEED NC 2009 Certification LEED NC 1.0 LEED NC 2009 Certified 2 6 - 3 2  40 - 4 9  Silver 3 3 - 3 8  50 - 5 9  Gold 3 9 - 5 1  60 - 7 9  Platinum 5 2 - 7 0  80   Table 4. Energy & Atmosphere Category in LEED NC 1.0 and LEED NC 2009 Criteria LEED NC 1.0 LEED NC 2009 Fundamental Building Commission Prerequisite 1  Prerequisite 1  Minimum Energy Performance  Prerequisite 2  Prerequisite 2  Fundamental Refrigerant Management  Prerequisite 3  Prerequisite 3  Optimize Energy Performance  Varies  Varies  On -  Site Renewable Energy 1 - 3  1 - 7  Enhanced Commissioning 1  2  Enhanced Refrigerant Management  -  2  Measurement and Verification  1  3  Green Power  1  2     10   There is also a considerable difference in the optimized energy performance criteria. In LEED 2009, new buildings and existing building renovations are completely separated, leading to distinct performance requirements.  Table 5. Optimized Energy Performance Criterion for LEED NC 1.0 [4]   Table 6. Optimized Energy Performance Criterion for LEED NC 2009 [5]       11   d. Weather Normalization Technique In heated or cooled buildings like UBC Friedman Building, energy consumption tends to depend on the outside air temperature. If the outside air temperature is cold, then energy is needed for heating to provide thermal comfort to the building occupants. App arently, the colder the outside air temperature is, the more energy is needed. If the outside air temperature is warm, then energy is needed for cooling to provide thermal comfort to the building occupants. Apparently, the warmer the outside air temperature is, the more energy is needed.  “teather normalinjation”, or “weather correction” techniƋues are used very often for comparing fairly energy consumption figures. So, when this normalization is very useful, because it allows us to compare fairly the energy consumption per year and is used to identify any changes in a building͛s energy consumption.  Weather normalization of energy consumption uses degree days. Degree days is a simplified form of historical weather data. Degree days are used in analyzing the relationship between energy consumption and outside air temperature. This process is often used to identify excess consumption and to quantify the savings from improvements in energy efficiency.  There are two main types of degree days: Heating de gree days (HDD) and Cooling degree days (CDD). Heating degree days (HDD) are used for calculations that relate to the heating of buildings and Cooling degree days (CDD) are used for calculations that relate to the cooling of buildings. Heating degree days are defined relative to a base temperatureͶthe outside temperature above which a building needs no heating. The base temperature varies from country to country. In Canada, heating degree- days for a given day are the number of degrees Celsius that the mean temperature is below 18°C. If the temperature is equal to or greater than 18°C, then the number will be zero.           12   e. Vancouver Climate Condition  As indicated in a previous study  by Sina Radmard and Nima Khalkali Shijini , Vancouver is situated at latitude of 49.2505 0 N and longitude of 123.111 9 0 W and has the following climatic specifications [ 6 ] :   Average 2100 hours of sunshine per year   Minimum average daily solar irradiation of 2.5kWh/m 2 . This daily average depends on inclination angle, and for Vancouver has the boundary conditions of 3.2 kWh/m 2  for horizontal surface and 2.5 kWh/m 2 for vertical surface. Although Vancouver is well known for its cloudy weather condition, its average solar potential is slightly less than Miami as an example ( only 8% less on annual basis as indicated in Figure 1)      Figure 8. Averages solar irradiation of Vancouver compared to Miami [6]     13   i. Temperatures The annual average temperature in Vancouver is 10.4  °C at the Airport  and it is one of the warmest in Canada. Vancouver temperatu re ranges on average from 0.8 0 C in December to 22.2 0 C in August as indicated in figure 9 below.  Unusually for a Canadian city, Vancouver has relatively mild winters with little snow. The cold air from the Arctic that sweeps over the rest of Canada in winter is unable to reach Vancouver. The Rocky Mountains block it.  Combine the lack of Arctic air with the mildness of sancouver͛s location on the shores of the Wacific Kcean and it͛s not surprising that sancouver is the warmest of Canada͛s major metropolitan cities in winter by far. Snow depths of greater than 1 cm are seen on about 10 days each year in Vancouver compared  with about 65 days in Toronto.  sancouver has one of the wettest and foggiest climates of Canada͛s cities. t times, in winter, it can seem that the rain will never stop. Compensating for the wet winters, Vancouver usually enjoys excellent summer weather characterized  by very pleasant, warm days with abundant sunshine. Vancouver also differs from most other Canadian cities in that it has a genuine spring and fall/autumn. In many Canadian cities it often seems that warm, summer weather replaces frigid, winter weather in a matter of a very few weeks or even days. Vancouver has a western maritime climate;  hence its weather can be changeable throughout the year. Vancouver is less windy than most other Canadian cities [ 7 ] .   Figure 9. Average temperature of Vancouver [6]   14   ii. Daylight  Figure 10. Daylight in Vancouver [8] Winters in Vancouver can be quite dark. The relatively high latitude means early sunsets (as early as 4:15 pm) and late sunrises (as late as 8:10 am).   From November to February, on average more than 70% of the already short daytime is completely cloudy in Vancouver .  A different pattern can be seen on summers. July and August are the months with the higher percentage of daylight.                15   4. Energy Performance Analysis a. Modelled and Measured Energy Performance DCt Consultant͛s made several simulations to predict the energy performance of the renovated building using EE4 software. The most recent revision could be seen below.   Figure 11. Predicted Energy Performance [9] As seen in the predicted energy performance above, renovation of Friedman building was aimed have 34% less energy consumption compared to reference building (MNECB). The EE4 model used the assumption which can be seen in Appendix A.  To verify the modelled energy performance, annual energy consumption of the building were then analyzed and compared as follows. Both electricity and steam consumption were taken directly from the meter data at the building. To properly convert the steam consumption to the actual natural gas consumption of the building, the efficiency of the steam distribution system in UBC was taken into account. According to Joshua Wauthy, Energy Conservation Engineer from UBC Building Operations, overall efficiency to convert natural gas to s team was approximately 60% (80% plant efficiency and 75% distribution system efficiency). Because of this, 1 lbs of steam (1.055 MJ of steam) delivered to Friedman building required approximately 1.76 MJ of natural gas.  This was consistent with the value which was used by MCW Consultants Ltd. in their simulation.    16   It should be noted that UBC were planning to convert the steam system to hot water system during the time of this study. Changing the system would increase the overall efficiency of the system to about 84.5% (87% plant efficiency and 97% distribution system efficiency).  Table 7. Energy Consumption Comparison Year Predicted 2010 2011 2012 2013 Electricity (MJ) 1,118,044  2,027,828  2,003,282  2,057,401  2,198,320  Steam (MJ)   1,036,048  1,347,065  1,481,742  1,922,850  Natural Gas (MJ) 2,958,529  1,729,218  2,247,237  2,471,911  3,207,788  Total Energy (MJ) 4,076,573  3,757,046  4,250,518  4,529,312  5,406,109  % Difference  - 7.84%  4.27%  11.11%  32%    Figure 12. Annual Energy Consumption of Friedman Building based on the Meter Data 050 0,0001,00 0,0001,50 0,0002,00 0,0002,50 0,0003,00 0,0003,50 0,0004,00 0,0004,50 0,000Energy (MJ) Annual Energy Consumption ElectricitySteam2 0 1 0  201 3  201 2  201 1    17    Figure 13. Annual Energy Consumption of Friedman Building, Taking Energy Conversion Ration from Natural Gas to Steam into Consideration  Based on the table and figures above, without considering the conversion ratio of natural gas to steam, the building annual energy consumption was actually better or comparable to the predicted value. However, once the energy distribution system was taken into account, the building performed much worse than expected, with only the performance in year 2010 was actually better than expected.   Electrical energy consumption of the building through year 2010 - 2 013 was consistently off by up to almost 100% compared to the predicted value. Interestingly, there was also a noticeable increase in year 2013 which would be discussed further in the report.  On the other hand, natural  gas consumption of the building increased steadily throughout the year. There were several factors which might cause this phenomenon: changes in climate and building thermal performance degradation over time. To investigate these effects, monthly and daily energy demand were investigated in the following section.  b. Monthly and Daily Energy Demand Trend Using Pulse Energy Dashboard for UBC, the monthly electrical and steam demand could be analyzed. In figure 11 - 18, actual energy demand for year 2010 - 2 013 were compared to the typical values predicted, “based on historical behaviour and correlates with weather conditions, time of the day, day of the week, month, season, and other available variables [ 10 ] .” 01,00 0,0002,00 0,0003,00 0,0004,00 0,0005,00 0,0006,00 0,000Energy (MJ) Annual Energy Consumption ElectricityNatural Gas2 0 1 0  2 0 1 3  2 0 1 2  201 1    18    Figure 14. Electrical Demand in Year 2010   Figure 15. Steam Demand in Year 2010   19    Figure 16. Electrical Demand in Year 2011   Figure 17. Steam Demand in Year 2011   20    Figure 18. Electrical Demand in Year 2012   Figure 19. Steam Demand in Year 2012   21    Figure 20. Electrical Demand in Year 2013   Figure 21. Steam Demand in Year 2013   22   As seen in figure 14 - 21  above, most data points were higher than the typical values, most notably in the steam consumption data. This strongly suggest that the thermal performance of the building degraded over time. Furthermore, there was also a notable increase in electrical energy demand after July 2013. The baseline electrical values were considerably higher compared to the typical/predicted values. This was most likely caused by the additional equipment installed in the building which will be discussed in section 5.  To further clarify the contributions of these factors, daily energy demand of the building were also analyzed. Since it was not feasible to analyze all 365 days in a year, representative time of the year was chosen based on the energy demand distribution which can be seen in the figures below.  Figure 22. Electricity Demand Distribution for Year 2013 7%  7%  8%  8%  8%  7%  10%  10%  9%  9%  9%  8%  Electricity Distribution for 2013 januaryfebruarymarchaprilmayjunejulyaugustseptemberoctobernovemberdecember  23    Figure 23. Steam Demand Distribution for Year 2013  Figure 24. Electricity Demand Distribution 2012  15%  11%  11%  10%  4%  1%  0%  1%  2%  11%  14%  20%  Steam Demand Distribution for 2013 januaryfebruarymarchaprilmayjunejulyaugustseptemberoctobernovemberdecember8%  8%  9%  8%  8%  7%  8%  9%  8%  9%  10%  8%  Electricity Demand Distribution 2012 JanuaryFebruaryMarchAprilMayJuneJylyAugustSeptemberOctoberNovemberDecember  24    Figure 25. Steam Demand Distribution 2012  Figure 26. Electricity Demand Distribution 2011 17%  13%  15%  8%  4%  1%  0%  0%  1%  6%  14%  21%  Steam Demand Distribution 2012 JanuaryFebruaryMarchAprilMayJuneJylyAugustSeptemberOctoberNovemberDecember8%  8%  9%  8%  8%  8%  9%  9%  9%  9%  8%  7%  Electricity Demand Distribution 2011 JanuaryFebruaryMarchAprilMayJuneJylyAugustSeptemberOctoberNovemberDecember  25    Figure 27. Steam Demand Distribution 2011  Figure 28. Electricity Demand Distribution 2010 16%  16%  12%  8%  3%  1%  1%  0%  1%  7%  16%  19%  Steam Demand Distribution 2011 JanuaryFebruaryMarchAprilMayJuneJylyAugustSeptemberOctoberNovemberDecember8%  7%  9%  8%  8%  8%  9%  9%  9%  9%  8%  8%  Electricity Demand Distribution 2010 JanuaryFebruaryMarchAprilMayJuneJylyAugustSeptemberOctoberNovemberDecember  26    Figure 29. Steam Demand Distribution 2010 Based on figure 22 -  29 , one day in August and December were chosen as the representative time where electricity and steam energy demand were almost the highest respectively.  In figure 30 and 31 below, daily electricity demand and outdoor air temperature for the first Wednesday in August were plotted and compared.  15%  15%  14%  8%  4%  2%  1%  - 1%  1%  4%  15%  21%  Steam Demand Distribution 2010 JanuaryFebruaryMarchAprilMayJuneJylyAugustSeptemberOctoberNovemberDecember  27    Figure 30. Daily Electricity Consumption on the First Wednesday in August  Figure 31. Outdoor Air Temperature on the First Wednesday in August As seen in figure 30 and 31 , electricity demand after considering the outdoor air temperature variation were relatively similar for year 2010 - 20 12. However, there was a notable jump in electricity consumption during off- hour for year 2013. This finding was consistent with other days in the same month.  In figure 32 and 33  below, daily steam demand and outdoor air temperature for the first Wednesday in December were plotted and compared. 02040608010012002:00 04:45 07:30 10:15 13:00 15:45 18:30 21:15 00:00Power(kWh) Time Daily Electricity Demand 2010 2010 Typical 2011 2011 Typical2012 2012 Typical 2013 2013 Typical05101520253002:00 04:45 07:30 10:15 13:00 15:45 18:30 21:15 00:00Temperature(oC) Time Daily Outdoor Air Temperature 2010 2011 2012 2013  28    Figure 32. Daily Steam Demand on the First Wednesday in December  Figure 33. Outdoor Air Temperature on the First Wednesday in December Unlike the similar values between the typical and actual daily electric ity demand, there were increasing gaps found in the steam demand. Furthermore, the steam consumption throughout the day was relatively constant. There were no clear indications of typical work - hours in the figure. This was expected since there were relatively small numbers of students in the building in December. This variation in occupancy pattern will be further discussed in section 5 a.  010020030040050060070080002:00 04:45 07:30 10:15 13:00 15:45 18:30 21:15 00:00Mass Flow (lb/hr) Time Daily Steam Demand 2010 2010 Typical 2011 2011 Typical2012 2012 Typical 2013 2013 Typical-6-4-20246802:00 04:45 07:30 10:15 13:00 15:45 18:30 21:15 00:00Temperature(oC) Time Daily Outdoor Air Temperature 2010 2011 2012 2013  29   c. Weather Normalization of Energy Consumption for UBC Friedman Building The procedure is described in Energy Lens website  [ 11 ] . Before proceeding to the normalization procedure the weather- dependent and non- weather- dependent should be defined. It is very common for a single energy meter to measure both weather- dependent and non- weather-dependent energy consumption together. For example, a building with electric heating might have a single electricity meter measuring all its electricity consumption (heating, lighting, equipment etc).   In degree - day analysis, energy consumption that does not depend on the weather is often referred to as “baseload” energy consumption. /t generally comes from energy uses that are not directly involved with heating or cooling the building; examples include electric lights, computer equipment, and industrial processes. For the purposes of the degree - day- based calculations, it is usually assumed that a building͛s baseload energy consumption is constant throughout the year. In UBC Friedman Building, natural gas is used for heating and the baseload kWh has not to be subtracted from the raw figures. This should have been done in case of the energy consumption (specifically, natural gas) was not 100% degree - day dependent and so, the raw energy consumption figures would contain baseload energy consumption as well as degree- day- dependent energy consumption.  Heating degr ee days are used to normalize the energy consumption of a heated building so that, the normalized figures can be compared on a like - for- like basis . So, for UBC Friedman Building, heating degree days enable us to calculate normalized energy consumption figu res for 2010, 2011, 2012 and 2013. The procedure is described below and the results of these calculations can be seen on Table 9 .  Ɉhe first step is to find the total heating degree days for the years of our interest 2010, 201 1, 2012 and 2013. Total heating degree days can be taken from Table 8  and can be seen on Figure 34 , but they are presented in more detail on Figure 35  [ 12 ] .  The second step for the normalization of the annual energy consumption figures of UBC Friedman Building was the calculation of the kWh per degree day for each kWh energy -consumption figure. By dividing by the degree factors out the effect of outside air temperature, and the resulting kWh per degree figures can be compared fairly.   The third step for the normalization of the annual energy consumption figures of UBC Friedman Building was to multiply the Ŭth per degree day figures by a single “average year” degree- day value. In this case, 2,785.664 degree days were used as the multiplier- an average yʹear value   30   calculated from the last Ϯϱ years͛ ;ϭϵϴϵ- 2013) worth of degree - day data from Vancouver, BC.  T.  The heating degree days over the last 25 years (1989 - 2013) are taken from Table 8  and they are presented schematically on Figure 34 . This gives normalized equivalents of the original kWh figures that can be fairly compared.  The choice of the multiplier could also be a 10 - or 20 - year average degree days or “standard degree days” ;to normalinje figures in such a way that they can be compared between regionsͿ. /t should be noted that, provided that just one multiplier is used ; and not “rolling” averagesͿ, it is not matter much what multiplier is used, as our figures will at least be proportionally comparable.     Table 8. Heating degree days over the last 25 years (annual data) for Vancouver Year 1989 1990 1991 1992 1993 1994 1995 1996 1997 Heating degree days 2869.2  2910.6  2893.6  2547.8  2778.8  2686  2544.4  3041.4  2685.5  Year 1998 1999 2000 2001 2002 2003 2004 2005 2006 Heating degree days 2538.5  2853.7  2908.1  2849.1  2841.2  2657.6  2526.9  2667.5  2724.7  Year 2007 2008 2009 2010 2011 2012 2013   Heating degree days 2879.5  3035.3  2924.9  2616.9  2981.8  2855.1  2823.5         31    Figure 34. Heating degree days over the last 25 years (annual data) for Vancouver     Table 9. Weather normalization of energy consumption Year Total Energy Consumption (Steam) Total heating degree days kWh per degree days Normalized kWh 2010 48 0338.33  26 16.9  183.55  51 1308.627  2011 62 4232.50  29 81.8  209.345  58 3164.830  2012 68 6641.94  28 55.1  240.497  66 9943.835  2013 89 1052.22  28 23.5  315.584  87 9110.988           32      Figure 35. Heating degree days over the last 5 years (quarterly data) for Vancouver   Figure 36. Normalized Natural gas consumption for years 2010, 2011, 2012 and 2013   33    Figure 37. Differences between Normalized and Actual Natural Gas Consumption for Years 2010, 2011, 2012 and 2013  Figure 36  shows the comparison between the actual weather- dependent energy consumption (natural gas consumption) and the normalized values. The differences between normalize d and actual natural gas consumption for years 2010, 201 1 , 2012 and 2013 can be seen on Figure 3 7 .  There are not considerable differences between the raw figures and the normalized figures. Actual natural gas consumption is slightly higher than the normalized natural gas consumption in years 2011, 201 2 and 2013. Respectively, normalized natural gas cons umption is slightly higher than the actual natural gas consumption in 2010. And, the more important is that the raw figures show that the natural gas consumption of UBC Friedman Building increases steadily from 2010 to 2012 and there is a more rapid increa se in 2013. Exactly the same pattern can be seen in normalized figures. Given these similar patterns, even though the normalization technique were relatively successful in taking into account the climate variation observed previously, the study wasn͛t sufficient enough in explaining the steady increase in energy consumption demand.        34   5. Potential Sources of Discrepancies Based on the findings above, there were several factors which might contribute to the performance gaps observed in LEED buildings  such as:  changes in energy demand, changes in design, inaccurate building plug load assumption, and building envelope degradation. This following section would explore each of these factors  in detail and summarized the efforts which the authors have done to investigate them. Furthermore, effects of these factors observed in Friedman Building would also be discussed. a. Changes in Energy Demand Throughout the year One of the most prominent factor s observed in the study is the change of energy demand throughout the year by weather condition, installation of new equipment, and changes in occupancy pattern.  i. Weather Contribution As discussed in the previous section, weather condition, especially outdoor air temperature, contribute significantly to the changes in energy demand. As seen in figure 37 , the normalization technique using heating degree days was able to remove the contri bution from these factors and should be considered for energy consumption analysis.  ii. Installation of New Equipment As observed in figure 20,  there was a noticeable jump in electrical energy demand after July 2013, this was most likely caused by the install ation of air conditioning unit for the teleconference devices in the Division of Physical Therapy of the School of Rehabilitation Science. This increase in energy demand was also observed in the building annual energy consumption. iii. Changes in Occupancy Pattern Changes in occupancy pattern in the building might have also contributed to the performance gap between predicted and measured value. This was evident in the annual electrical energy demand graphs which can be seen in figure 14,16,18, and 20.  In those figures, there were noticeable dips in electricity demand during the Summer term and holiday season in December. However, the contributions of changing occupancy pattern with the steam consumption weren͛t as obvious. After the assessment of the annual energy usage data, there were actually three different months which were of particular interest:  August (highest electrical consumption, almost the lowest steam consumption), December (highest steam consumption), and February (lowest electrical consumption).   35   To analyze the changes in occupancy pattern during these three months, c alendar information of year 2013  were used for the study of the occupancy pattern in several rooms which were chosen based on the recommendations the program administrators of the buildings. These rooms were considered as rooms with relatively high occupancies. They were: rooms 204  and 304 from the Physical Therapy  Division of School of Rehabilitation Sciences as well as Room 354  and 355 from School of Audiology and Speech Sciences.  dhe rooms͛ monthly room usage data (booked hours and approximate number of occupants  were studied to determine the occupancy pattern in the months of interest and identify any possible sources of the existing discrepancies.     Figure 38. Occupancy Pattern for Room 204-Feb 2013    36     Figure 39. Occupancy Pattern for Room 204- Aug 2013    Figure 40. Occupancy Pattern for Room 204- Dec 2013    37     Figure 41. Occupancy Pattern for Room 304- Feb 2013    Figure 42. Occupancy Pattern for Room 304- Aug 2013     38    Figure 43. Occupancy Pattern for Room 304- Dec 2013    Figure 44. Occupancy Pattern for Room 354- Feb 2013    39     Figure 45.Occupancy Pattern for Room 355  As seen in the figures above, the occupancy pattern of these rooms were different for each month and might contributed significantly to the peaks and dips  observed in the annual energy demand trend of the building. Even though the buildings had no mechanical cooling system, changes in occupancy pattern would change the plug load in the building.        40   b. Changes in Design before and after LEED Application The possibility of changes in Design before and after LE ED Application was investigated. Comparing the Leed Drawings (200 6) with the As - Built Drawings (2008), we can see that there are changes in Design before and after LEED Application. A new Air Handling Unit  is indicated in As Built Drawings which cannot be seen in LEED Drawings. Also, there are five New Single - Duct VAV Terminal Units indicated in As Built Drawings which cannot be seen in LEED Drawings. The new components are presented in Table 10 and 11. It should be noticed that there is additional air handling unit which was added after the LEED application submission. This might have caused the significant difference in predicted and measured electrical energy consumption rate.  Table 10. New Single-Duct VAV Terminal Units indicated in As Built Drawings compared to LEED Drawings    PRIMARYAIR FLOW (L/s)  HYDRAULIC HEATING COIL  ATTENJATOR SIZE (MM)   TAGS M ODEL  MIN  MAX  DESIGN  KW  L/s  DISCHARGE  INLET  MECHANICAL REMARKS  V3-2-05 SDV - 04  20  40  40  -  -  305 x203  102 ø  SINGLE DUCT VAV BOX  V3-2-07 SDV - 04  30  65  65  -  -  305 x203  102 ø  SINGLE DUCT VAV BOX  V3-2-08 SDV - 04  30  50  50  -  -  305 x203  102 ø  SINGLE DUCT VAV BOX  V3-3-07 SDV - 06  45  95  95  -  -  305 x203  152 ø  SINGLE DUCT VAV BOX  V3-3-08 SDV - 06  45  95  95  -  -  305 x203  152 ø  SINGLE DUCT VAV BOX    Table 11. New Air Handling Unit indicated in As Built Drawings compared to LEED Drawings REF DESCRIPTION WEIGHT LBS LOCATION  HEATING CAPACITY HYDRAULIC HEATING COIL SUPPLY  FAN  0/A Max/min L/S AHU-4 AIR HANDLING UNIT FOR BASEMENT  154  ROOM B002  25.13(85.7) BY HOT WATER  0.53(8.24)  TYPE: 1 ROW  944  250  944/95     41   c. Inaccurate Building Plug Load Assumption Most simulations used a certain plug load values based on the function of each space. For the renovation of Friedman building, average Energy Power Density was 4.30 W/m 2  or 0.40 W/ft 2 . This value was comparable with the ASHRAE 90.1 guideline.   Figure 46. ASHRAE 90.1 Guideline for Occupancy Density, Receptacle Density, and Service Hot Water Quantities. To qualitatively check the discrepancy in plug load estimation , a site visit was conducted by the authors to check if there were any energy intensive dev ices in the buildings which might have contributed to the performance gap between the predicted and measured energy. The photos of the typical rooms and devices in the building could be seen in Appendix C.  Based on the site visit results, there were no significant addition of plug loads except for the teleconference devices and lab equipment found in the building. However, the contributions of these devices to the overall electricity demand, which were off by a significant amount, were not clear. With the help of UBC electricians, the authors have explored the possibility of installing metering equipment in some of the energy intensive areas to investigate the contribution of plug loads to the overall energy consumption. Even though this plan was deemed feasible, it wasn͛t carried through because of time conflict. By the time the permission for this operation was granted, the spring term has come to an end.  d. Building Envelope Degradation Due to the time constraint of the project, the authors weren͛t able to analynje the envelope degradation phenomenon. However, based on the increasing annual energy consumption rate, this factor might have a significant role in affecting the thermal performance of the building, thus creating the performance gaps found in many LEED buildings. do fully investigate this phenomenon, it͛s recommended to do a long term study to monitor the thermal resistance value of building facades and leakages in the building.    42   6. Conclusions and Recommendations Based on the study on Friedman building, similar performance gaps as shown in previous study by New Building Institute [ 1 ]  were encountered. Annual electricity consumption of the building was consistently different by up to almost 100% compared to the modelled performance. Even though annual natural gas consumption was relatively better than predicted for the first year (2010 ), there was an almost linearly increasing trend found in year 2011 - 20 13, causing wider performance gaps for each year.  There were several sources of discrepancies identified in the study: changes in energy demand due to weather contribution, installation of new equipment, and changes in occupancy pattern; changes in design before and after the LEED application; inaccurate building plug load assumption; and building envelope degradation. While the contributions of each factor has been identified and analyze d, it was unfeasible to conduct investigation on buildings envelope degradation and measurement of actual plug load of the building. Nevertheless, the analysis methods laid out in the report should be considered for conducting similar investigation on other UBC LEED Buildings.      43   7. References [1]  Cathy Turner and Mark Frankel, "Energy Performance of LEED for New Construction Buildings," New Buildings Institute, Vancouver, Technical Report 2008.  [2]  MCW Consultants Ltd; Recollective Consulting;  Acton Ostry Architects Inc, "LEED Gold Upgrade Study for UBC Friedman Renovation," Technical Report 2008.  [3]  Canada Green Building Council, "LEED Canada - NC 1.0 Certification Review Report," LEED Certification Report 2011.  [4]  Canada Green Building Coun cil, "Rating System & Addendum for New Constructions & Major Renovations LEED Canada - NC Version 1.0," in LEED Green Building Rating System., 2004.  [5]  Canada Green Building Council, LEED Canada for New Construction and Major Renovations 2009., 2009.  [6]  Sina Radmard and Nima Khalkhali Shijini, "Small Footprint Net Zero Buildings for the Future of Metro Vancouver," University of British Columbia, Vancouver, Technical Report 2013.  [7]  The Climate and Weather of Vancouver, British Columbia. [Online]. http://www.livingin -canada.com/climate- vancouver.html [8]  Vancouver Int'l, BC, Canada: Climate, Global Warming, and Daylight Charts and Data. [Online]. http://www.climate - charts.com/Locations/c/CN7189 20 11 08 44 70.php  [9]  Henry Leung, "EA Credit1.1 - 1.10: Optimize Energy Performance," MCW Consultants, Memo 2011.  [10 ]  BC Hydro. Pulse Energy. [Online]. https://my.pulseenergy.com/help/reference/pointTypes?highlight=typical+value#c_typicalcurve  [11]  BizEE Energy Lens. Degree Days -  Handle with Care!. [Online]. http://www.energylens.com/articles/degree - days [12]  Vancouver Historical HEating Degree Days. [Online]. http://vancouver.weatherstats.ca/metrics/hdd.html     44   8. Appendix a. Modelling Parameters [13]    45      46       47      48      49   b. Drawings i. LEED Package      50   ii. As- Built Drawings     51   c. Site Visit Results and Photos i. Division of Physical Therapy, School of Rehabilitation Sciences ii. School of Audiology and Speech Sciences      

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