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Natasa Nord Vojislav Novakovic Frode Frydenlund

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Page 1: Natasa Nord Vojislav Novakovic - SINTEF...1 1. Aim and scope of the project The main goal of this project was to develop, verify, and implement suitable tools for estimating building

Natasa NordVojislav NovakovicFrode Frydenlund

Page 2: Natasa Nord Vojislav Novakovic - SINTEF...1 1. Aim and scope of the project The main goal of this project was to develop, verify, and implement suitable tools for estimating building

Lifetime commissioning for efficient operation of buildings

Copyright SINTEF Energi AS

Published: December 2012

Published by SINTEF Energi AS (SINTEF Energy Research)Sem Saelands vei 11NO-7034 Trondheim

In cooperasjon with NTNU (the Norwegian University of Science and Technology)

ISBN 978-82-594-3586-6www.sintef.no/energy

Cover by Astrid B. Lundquist/Shutterstock

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the property owners, contractors, a national agency promoting increased sustainability in energy consumption and generation, and a consulting company. The partners contributed with their experience, practical challenges, and case studies. We highly appreciate and thus would like to thank them for their valuable contributions.

Through the project lifetime, we have contributed to two international projects under the International Energy Agency (IEA) Energy Conservation in Buildings and Community Systems (ECBCS) Programme: Annex 47 and Annex 53. In this way, international experiences and ideas have been transferred into this national project. During this project, two PhD theses, three master’s theses, and more than 20 journal and conference articles have been published.

1. Aim and scope of the project 1

2. Partners and project organization 2

3. What is lifetime commissioning? 3

4. International collaboration 6

5. Lifetime commissioning internationally 8

6. Lifetime commissioning tools developed under this project 10

7. Necessity and importance of lifetime commissioning in Norwegian industry 24

8. Scientific and technical publications 26

9. References 27

This book is intended for building owners, project leaders, designers, contractors, operation and maintenance services, suppliers of building automation systems, and building authorities. It addresses topics that are interesting to all stakeholders focused on achieving significant and documented energy savings in place of simply using an intuitive approach. The book is written in a simple and descriptive way for a wide group of users.

The background for this book came from the results obtained through the National Project for Lifetime Commissioning and Energy Efficient Operation of Buildings (PFK). The project has lasted for eight years, and the last six were supported by the Norwegian Research Council. Seven industrial partners have been involved in the project through the eight years. The project partners were

Preface

Table of Contents

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1. Aim and scope of the project

The main goal of this project was to develop, verify, and implement suitable tools for estimating building energy performance during the lifetime of the building. The motivation for this project came from practical experience in building operation and maintenance, the fragmented nature of the building industry, and developments in building control and monitoring technologies. All serious industry players involved in the planning, construction, and operation of buildings have good intentions regarding high energy efficiency, safe operation, good indoor air climate, the rational use of energy, minimal impact on the outdoor environment, and sound economy. However, practical experience reveals that there are serious discrepancies between these goals and reality. The reasons for these discrepancies are manifold, including faulty design and construction, a lack of inspection in the construction phase, improper control strategies, aging of the HVAC components, and inadequate maintenance.

Lifetime commissioning (LTC), or continuous commissioning, has recently been recognized internationally as a promising technique with many different tools, methods, and activities that can help solve the above-mentioned challenges. The ASHRAE Guideline 2005 defines commissioning as the process of ensuring that systems are designed, installed, functionally tested, and capable of being operated and maintained, to perform in conformity with design intent and maintain optimal building conditions throughout the entire lifetime of the building [1].

LTC is relevant to building energy efficiency because it enhances the achievement of ambitious energy efficiency aims. How does LTC encourage energy efficiency and building CO2 emission reduction? In the building design phase, several objectives related to the total building

energy use, the building energy performance, and the indoor environment are defined. These objectives can be drawn from relevant standards, or building owners and users can design their own goals. For example, it has become popular for property owners and developers to take responsibility for the environment and to want to be recognized as “role models” in terms of energy efficiency and reduced environmental impact. The LTC tools and methods address and further these goals by monitoring the building construction process, taking-over process, and further operation and maintenance. In general, LTC can be defined as a quality control process for the building energy performance.

LTC as both a practical and a research topic is relevant for almost all building stakeholders during the lifetime of the building, including property owners, designers, contractors, operation and maintenance services, control and monitoring equipment suppliers, tenants, and occupants.

The LTC research and practical issues are related to the implementation of technologies from construction and other industries. For example, in oil industry and nuclear power plants, detailed plant documentation and monitoring are required because all of the subsystems are delivered with instrumentation already installed, making subsystem monitoring easy. However, monitoring the energy performance of a building can be challenging for a variety of reasons, including the low-cost and fragmented nature of the building industry, technological issues, lack of expertise and poor communication between players during the building’s lifetime, building operation and maintenance, ownership, and economic conditions. Therefore, LTC is intended to help transition the building industry from the intuitive approach that is currently employed in the operation of buildings to a more systematic approach that focuses on achieving significant energy savings.

LTC can be defined as a quality control process for the building energy performance.

.. monitoring the energy performance of a building can be challenging ..

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2. Partners and project organization

The National Project for Lifetime Commissioning and Energy Efficient Operation of Buildings (PFK) is a Knowledge-building Project with User Involvement (KMB) with stakeholders from the building construction industry including industrial companies, private and public entities, and R&D organizations as members.

The overall objective of the research project was to contribute to the implementation of lifetime commissioning of building HVAC systems so that this becomes a standardized way of building, operating, and maintaining buildings.

PFK should be developed into an internationally leading specialist environment for knowledge as well as research and development for the areas of quality assurance of efficient design and construction, proper and safe operation, efficient use of energy, and satisfactory indoor environments in buildings.

PFK was approved at the foundation meeting held on April 29, 2005. At this meeting were representatives of Telenor (property division), Statoil (property division), and Statsbygg; in addition, the consulting company ProTeknologi, together with the scientific environment at the Gemini Center Energy supply and Climatization of buildings at NTNU and SINTEF realized the necessity and decided to create PFK. Several other members joined later. The Research Council of Norway supported the program financially from 2007 to 2012.

During the eight years of its existence, the PFK Project has had the following seven industrial partners:

• Telenor (property division)

• Statoil (property divisions)

• Statsbygg – Norwegian Directorate of Public Construction and Property

• Forsvarsbygg - Norwegian Defense Estates Agency

• ProTeknologi / Norconsult - consulting company

• GK Norge AS - HVAC contracting firm, energy, building automation

• Enova SF

Gemini-Center Energy Supply and Climatization of Buildings at NTNU and SINTEF performed the majority of the activities and was also responsible for the daily management of PFK.

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3. What is lifetime commissioning?

There are many definitions for lifetime commissioning, all of which address the verification, documentation, monitoring, and optimization of building performance. In short, it can be said that lifetime commissioning is a quality-oriented process for verifying whether the performance of a building’s systems meet defined objectives throughout the entire lifetime of the building. In the past, commissioning has been solely understood as a process at the end of the construction of a building, also referred to as take-over. The new understanding is that commissioning is a continuous process that spans the early design phase to the operational phase. Consequently, all the design ideas and objectives are transferred further to the building maintenance. An illustrative figure detailing how the lifetime commissioning works throughout the entire lifetime of the building is given in Figure 1.

In Norway, the commissioning process for large buildings has only been viewed as the completion and take-over. It has not been considered to be a process from the start of the building project to the end of the lifetime of the building. The regulations in Norway describe the formalities concerning the take-over process, such as the contents of the completion protocol, routines for alteration work, procedures in the take-over, etc. It does not consider any routines that occur during the progress of the building project. Some major building owners have established separate commissioning routines based on approaches from the offshore and pharmaceutical industries.

For someone new to the issue, it can be difficult to understand what LTC is and why it is needed. However, to clarify the issue, here is a list what LTC is not:• an additional phase of a project• an isolated testing event• a testing, adjusting, balancing (TAB)• an equipment start-up

LTC will likely involve TAB, equipment start-up, and various tests, but these are just a

part of the larger whole of the commissioning process as it occurs throughout all phases of a project.

3.1. Why is lifetime commissioning necessary?There is an increasing realization that many buildings do not perform as intended by their owners. Reasons for this deviation in performance include faulty design and construction, malfunctioning equipment, incorrectly configured control systems, and inappropriate operating procedures [2]. Additionally, HVAC components easily suffer from complete failure (hard fault) or partial failure (soft fault) due to abnormal physical changes, aging of the HVAC components, or inadequate maintenance [3]. Although building performances are normally supervised by Building Energy Management System (BEMS), when a fault occurs in the system, the BEMS programs that are currently available do not adequately assist in finding the underlying cause of the fault. Therefore, diagnosis of the defect is left to the operator [4]. However, both an increase in energy use and a degradation of the indoor environment follow each fault, regardless of the source of the fault.

Figure 1. Lifetime commissioning brings together building information

Maintenance

Operation

Acceptance

Construction

Design

Pre-design

LifetimeCommissioning

.. many buildings do not perform as intended by their owners.

.. the BEMS programs that are currently available do not adequately assist in finding the underlying cause of the fault.

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A short list of some of the faults in three typical HVAC systems is given in Table 1. The faults are chosen from IEA - ECBCS Annex 25, which obtained these results using a survey among designers, constructors,

Figure 2. Placing the lifetime commissioning

Table 1. List of some typical faults in three different systems listed in Annex 25 [4]

System

Hydronic heating system

Chillers and heat pumps

VAV air handling unit

Fault

Heating imbalance between different parts of the building

Over- or under-sizing of radiator in certain rooms or specific parts of the system

Heating curve badly tuned

Incorrect calculation of the optimum start or stop by the operational mode controller

Leakage of the control valves for secondary circuits

Compressor not pumping

Plant undersized

Too much pressure drop in evaporator

Condensation due to improper thermal insulation

Excessive internal heat generation

Insufficient noise control

Air filter being clogged

Comment

Design fault

Design fault

Operating fault

Operating fault

Operating fault

Maintenance fault

Design fault

Design fault

Fabrication fault

User fault

Design and fabrication fault

Maintenance fault

and operators. The list classifies faults based on the system types, the faults that were recognized, and the project phase where the faults were recognized (design, maintenance, due to user, etc.).

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3.2. Tools and methods for lifetime commissioningThe tools and methods for lifetime commissioning can be numerous. Some of them were developed during this project and are presented later in text. A simple explanation of how these tools work can be stated as the organization and utilization of building information and BEMS data, and the provision of useful information to building operators.

BEMS provides a large amount of data about the building performance, and both caretakers and managers are able to use the data. Caretakers can use the performance data for maintenance and improving the building performance. Energy management requires technical knowledge to understand how well or poorly a building and its systems are functioning, to identify opportunities for improvement, and to implement effective upgrades. Well-trained and diligent building operators are very important to the financial success of energy management [5]. To utilize BEMS data more successfully for maintenance, it is necessary to provide useful information about the building performance to the caretakers so that they actually understand what is really happening in a building.

Regardless of the applied logic in the background of a commissioning tool, the main purpose of the tools is the assessment of building performance. Building assessment tools can be organized into three categories: benchmarking, energy tracking, and diagnostics. Benchmarking is a macroscopic level of performance assessment, in which metrics are used to measure the performance of the building relative to other buildings. Buildings are typically benchmarked using coarse data, often from utility bills, with some procedure for normalization for variables such as weather and floor area. Tracking the energy performance over time is a logical enhancement of one-time benchmarking. Energy tracking can result in an overall understanding of load shapes. Although the data needed for diagnostics are more extensive than for energy tracking, this

jump in complexity is essential to obtain the information needed to aid in correcting problems. Benchmarking and energy tracking are useful in identifying inefficiencies at the whole building level and focusing efforts toward large energy end-uses, while diagnostics allows the detection of specific problems and helps target the causes of these problems [6].

Commissioning tools for building performance assessment can be defined as:• functional performance testing (FPT),• fault detection and diagnosis (FDD).

FPT is the process of determining the ability of the HVAC system to deliver heating, ventilating, and air conditioning in accordance with the final design intent [5]. FPT is more important during the construction and delivering phase of building, while FDD tools are necessary during operation and maintenance. FDD tools can be manual or automated. Manual tools imply different guidelines for the building operators; automated commissioning involves analyzing the system performance to detect and diagnose problems (faults) that would affect the operation of the system during normal use [7].

The application of a commissioning tool is related to a tool realization and a tool user. These tools can be automated or manual; automated tools are embedded in the HVAC control system. An important means for the practical application of any tool in existing building is BEMS.

3.3. Where to place lifetime commissioning in everyday life?LTC can be applied throughout the building lifetime and is a team-oriented process [5]. Because LTC should be understood as a tool for improving the building performance throughout its lifetime, it is recommended for existing buildings as well as the construction of new buildings. By using different tools and methods, LTC can be implemented throughout the entire building lifetime for different purposes as shown in Figure 2.

Well-trained and diligent building operators are very important to the financial success of energy management.

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Through this project, we have contributed to two international projects established by International Energy Agency’s (IEA) Implementing Agreement on Energy Conservation in Buildings and Community Systems (ECBCS). The IEA - ECBCS Programme carries out research and development activities with the goal of near-zero energy and carbon emissions in the built environment. The research and development activities focus on the integration of energy-efficient and sustainable technologies into healthy buildings and communities. ECBCS projects and activities have produced long-lasting decision-making tools and integrated systems technologies [8]. The projects under ECBCS are called Annexes with a successive number. These projects are very good means of exchanging information among practices in different countries and disseminating relevant information to national practitioners. IEA - ECBCS supported several projects more or less directly related to LTC: Annexes 25, 40, 47, and 53.

4.1. Contribution to Annex 47 and Annex 53Our research team participated in three of these four consecutive projects: Annexes 40, 47, and 53. Annex 40 was accomplished before our national PFK project was established. Our participation here was funded through the SMARTBYGG project and our activities and achievements created the scientific bases for both the later establishment of the PFK project and our participation in the two new Annexes.

Annex 47, named the Cost-Effective Commissioning for Existing and Low Energy Buildings, was launched in 2005. The goal of IEA - ECBCS Annex 47 was to enable the cost-effective commissioning of existing and future buildings in order to improve their operating performance so that low-energy buildings are possible. The commissioning techniques developed through this Annex will help transition the industry from the intuitive approach that is currently

4. International collaboration

employed in the operation of buildings to a more systematic operation that focuses on achieving significant energy savings [9]. Annex 47 lasted for three years.

The key outputs of IEA - ECBCS Annex 47 include the following:

• Methods and tools for the commissioning of advanced systems and low energy buildings;

• Methods and tools for field application;

• Information on the costs and benefits that can be used to promote the wider use of commissioning;

• Flow charts and data models for the initial commissioning of advanced and low- energy building systems.

Our contributions in Annex 47 were related to commissioning tools for existing buildings, a cost-benefit analysis, and a data model for commissioning. In the spring of 2006 we hosted the Annex 47 Expert Meeting in Trondheim.

Annex 53, named the Total Energy Use in Buildings: Analysis and Evaluation Methods, was launched in 2009. The aim of this project was to understand and identify the most significant factors of the real energy use in buildings. The motivation for the project came from the fact that there is often a significant discrepancy between the designed and the real total energy use in buildings, in which a complex array of factors plays a significant role, including the user / occupant behavior. The ultimate outcome of this project is strengthening the robust prediction of energy usage in buildings, thus enabling the proper assessment of short- and long-term energy measures, policies, and technologies. The main objectives are to:

• develop a new methodology for the analysis of building energy use;

• demonstrate how these data can be used to provide meaningful indicators of the energy performance of buildings;

.. there is often a significant discrepancy between the designed and the real total energy use in buildings ..

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Figure 4. Case building from Norway in Annex 53

• develop methodologies and technologies for the long-term monitoring of the energy use in buildings [10].

The research work on Annex 53 defined six driving factors of real energy use in buildings. These factors are shown in Figure 3. Based on our experience in building data collection and energy monitoring, we had

Figure 3. Influencing factors of building energy use defined in Annex 53 [10]

detailed data on two case buildings to contribute to Annex 53. One of our case buildings was used as a leading example of how well a building should be documented. By using our data, Chinese colleagues from Annex 53 made an illustrative poster as shown Figure 4. We also made contributions related to statistical methods and monitoring technologies.

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The level of commissioning activities and implementation is different around the world. A brief description on the state of building commissioning is presented here. The states in Europe, North America, and Japan are presented.

Europe: For most of the countries in the European region, with the exception of the UK, the commissioning process is quite new. However, the European Commission established the European Performance of Buildings Directive, EPBD (EC 2002), to promote the improvement of energy efficiency and building performance. EPBD sets a framework for the calculation of energy demands and for the energy certification for each building. In addition, it creates a guide for arrangements for inspections and control to see that the directive is followed. According to reports from the member states, the EPBD poses significant challenges in terms of its practical implementation, including difficulties associated with the transfer of requirements into existing building practices under a range of climates. However, because the commissioning process is well aligned with the goals of the EPBD, several national research programs are introducing commissioning tools as a means to address the requirements of the directive. In many countries, commissioning tasks are focused on the building handover or performed as part of the facilities management. However, for commissioning to have a real impact on savings, the process must begin at the pre-design phase, where changes are easier and more cost-effective to make. The increased attention to energy efficiency in buildings will lead to a greater application and consistency of commissioning through the building lifetime [11].

North America: In North America, the concept of building commissioning began with the Code of Practice for Commissioning Mechanical Systems in Buildings that was developed in 1986 by the Standing Committee of Consulting Engineers and Mechanical

5. Lifetime commissioning internationally

Contractors of British Columbia. Today there are several industry-recognized guidelines on the commissioning process: ASHRAE Guideline 1-1989, the HVAC Commissioning Process (revised in 1996), and ASHRAE Guideline 0-2005, the Commissioning Process. Although building systems commissioning is an established practice in both Canada and the USA, the process is not widespread. Many of the existing resources are focused on conventional HVAC systems and there is a need for information on other types of systems, particularly due to increased interest in non-conventional, low energy systems.

In Canada and the USA, the commissioning awareness has increased through professional organizations, certification programs (e.g., LEED), large-owner mandates, and energy-efficiency initiatives. LEED provides a framework for assessing a building’s performance and for achieving sustainability goals. Commissioning is a requirement to achieve LEED certification for both new and existing commercial buildings. However, there is a need for greater awareness of both the costs and benefits of commissioning to increase demand and a need for more training and certification of commissioning providers to increase the supply.

The research institute in Canada, Natural Resources Canada, developed commissioning software called DABO. DABO is a software tool running in the central building operator station. It analyses data from the BEMS to identify faults in the operation of energy-consuming equipment and systems. DABO uses expert knowledge to identify these faults through the use of a hybrid knowledge-based system composed of an Expert System and a Case-Based Reasoning module. DABO detects malfunctioning electromechanical equipment and identifies operation problems with its 800 logical rules. In addition, DABO conducts a more in-depth analysis of operation faults in electromechanical systems and identifies under- or over-designed components with its 275 performance indices.

For most of the countries in the European region, with the exception of the UK, the commissioning process is quite new.

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Finally, this software produces fault detection reports and performance analysis reports and recommends corrective measures to be implemented by the maintenance team even before these faults have an impact [12].

The Energy Systems Laboratory at the Texas A&M University was a pioneer in developing commissioning as a continual process. The Energy Systems Laboratory has developed the Continuous Commissioning® (CC) process to improve comfort and performance using cost-effective measures. CC® incorporates the best of retro-commissioning techniques into a process that has achieved superior performance in over 300 buildings around the globe. The objective of CC® is to produce a rapid payback while providing sustained improvement to building performance according to the facility’s actual use. The Energy Systems Laboratory and its licensed partners have access to the tools, research, and expertise that make the Continuous Commissioning® process effective[13].

Japan: In 2006, building energy performance reporting became mandatory under the Energy Conservation Law. The reports are based on simple performance tests of the components and systems that have the largest impact on the energy consumption of heating, ventilation, and air conditioning systems. In practice, there is significant variation in the implementation approach because no standard test procedures are specified and it is unclear whether relevant problems could be investigated adequately through the data contained in the reports. Therefore, aspects of the commissioning process are drawing more attention in Japan’s building sector. In existing buildings, various approaches for retro-commissioning are commonly implemented, but initial commissioning for new construction is not common.

In 2005, the technical committee on commissioning of the Society of Heating, Air-Conditioning and Sanitary Engineers of Japan (SHASE) issued a guideline on the building services commissioning process. The Building Services Commissioning Association (BSCA), a nonprofit organization launched in 2004, provides seminars about commissioning technologies in major cities and has undertaken cooperative activities with Asian countries such as China (including Hong Kong), Taiwan, and Korea. It also continues to compile commissioning documentation and tools from actual commissioning projects and research. BSCA’s strategy is to establish a certification program for commissioning engineers, including the Commissioning Authority, and to educate the construction industry and related government sectors.

Energy policy is playing an important role. The Ministry of Economy, Trade and Industries is interested in a new business model based on building commissioning to enhance the energy efficiency of new and existing buildings, and The Ministry of Land, Infrastructure and Transportation is promoting the use of lifetime energy management with a newly developed simulation tool. The market demand for commissioning is believed to be strong but mandates, based on energy and environmental policy, are needed for building owners to apply building commissioning to new construction [11].

The Energy Systems Laboratory at the Texas A&M University was a pioneer in developing commissioning as a continual process.

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6.1. Simulation tools for FDD and building optimizationDifferent issues can arise during building operation, and it can be challenging to handle these issues. Additionally, there is a need to optimize the building operation, but this issue is also challenging. Simulation tools create many opportunities to test different types of faults and to optimize building

operation. Natasa Nord (Djuric) received his PhD with the topic “Real-time supervision of building HVAC system performance”. In this PhD thesis, several examples with design and operation optimization are shown. Further, in this thesis real building operation data are used to detect faults in and optimize the building operation. Simulation tools are used for both building optimization and fault detection. The use of simulation tools creates many opportunities to try and test possible operation faults and to optimize the building operation. The thesis presents several methods for improving the performance of the HVAC system in existing buildings, generated by using simulation-based tools and real data. In addition, this thesis shows an advanced utilization of BEMS data for fault detection and building optimization. Coupled simulation and optimization programs (EnergyPlus and GenOpt) are utilized for improving the building energy performance by improving the design and the control strategies in the HVAC systems [14].

Simulation tools create the possibility to simply try different operation scenarios, such as component faults, equipment aging, poor control, etc. By using the simulation tools EnergyPlus and TRNSYS, several FDD rules have been generated. These rules have been established for the air cooling system and the hydronic heating system. The rules can diagnose the control and the component faults. An example of the simulation results and how different faults in a hydronic heating system can influence the indoor air temperature are shown in Figure 5. Finally, by analyzing the causes and the effects of the tested faults, useful information for the building maintenance has been descriptively explained [14]. Further, in this PhD thesis, an advanced utilization of BEMS data coupled with a MATLAB analysis is conducted. MATLAB (matrix laboratory) is a numerical computing environment intended primarily for numerical computing [15].

6. Lifetime commissioning tools developed under this project

Figure 5. Influence of the faults in hydronic heating system on the indoor air temperature

Figure 6. Consequences of disconnected outdoor temperature sensor on the indoor temperature and energy use

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The real data obtained from BEMS along with additional measurements have been utilized to explain faults in the hydronic heating system. To couple real data and the simple heat balance model, a procedure for the model calibration by use of an optimization algorithm has been developed. Using this model, three operating faults in the hydronic heating system have been investigated. In Figure 6, the consequences of a disconnected outdoor temperature sensor on the hydronic heating system are shown. The outdoor temperature sensor is used as an input to control the temperature of the supply water to the hydronic heating system. The relation between the outdoor and supply water temperature is defined by an outdoor temperature compensation curve. If the outdoor temperature compensation curve is not properly adjusted to the building purposes, a desired indoor temperature cannot be achieved [14].

The most important conclusions in this PhD thesis are related to the practical connection of the real data and simulation tools. Further, for a complete understanding of the system faults, it is necessary to provide lots of information and real-life data. Although BEMS provides many building data, it was proven that BEMS is not completely utilized in the current practice. Therefore, the control strategies can always be improved and tuned to the actual building demands using the simulation and optimization tools. As shown above, many different FDD rules for HVAC systems can be generated using the simulation tools. These FDD rules can be used as manual instructions for the building operators or as a framework for the automated FDD algorithms [14].

Figure 7. Main window of the tool for identifying operation and maintenance problems

.. for a complete understanding of the system faults, it is necessary to provide lots of information and real-life data.

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6.2. Using building energy monitoring to verify building energy performanceA commissioning tool for identifying the operation and maintenance problems is developed by Marko Masic as a part of his PhD thesis: ’’Using building energy monitoring to verify building energy performance’’. This tool utilizes the hourly energy use data to model building energy performance affected by inner and outer factors. Outer factors are outdoor air temperature, solar gains, and wind; the building operation is considered to be an inner factor. The tool developed in this PhD can perform the following analysis: develop a linear regression model for space heating and ventilation energy use and assess the operation and maintenance problem. This tool is developed on the MATLAB platform [15]. The tool is used for problem detection in

the operation of 19 buildings at the campus of Norwegian University of Science and Technology (NTNU) [16]. The main window of the tool is shown in Figure 7 [16]. The main capabilities of the tool are shown in Figure 7. For example, it is shown that the tool analyzes the building responses by comparing actual and modeled energy use for an observed analyzing period. For example, in Figure 7, two different operation regimes are recognized, which are indicated by the two energy signature lines.

In this PhD thesis, the operation and maintenance problems are detected by comparing actual and modeled heat consumption. The resulting predictions are accurate enough to recognize system operation faults. Energy signature lines are determined by using linear regression.

Figure 8. 3D plot of actual heat consumption

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This thesis also discusses the influences that determine space heating and ventilation system heat consumption. The results show that data with different resolutions capture heat consumption variations to different degrees. Data with higher resolutions introduce more information into the analysis. For example, in Figure 8 a 3D plot of the hourly heat energy use is shown. The horizontal plane is defined by days and hours of a day, while the vertical axis is the heat energy use. By using a 3D plot as in Figure 8, it is simple to identify deviations and biases in building operation. Two peaks in Figure 8 (one upward and the other downward) are good examples how abnormal heat energy use can be identified. Heat consumption prediction models for four types of grouping data (hourly, hour-of-day grouping, mean values grouped by regimes, and daily data) are compared as well.

6.3. Demand control of energy and indoor environment performances - a case studyAina Eide researched both the project assignment and her Master’s thesis within the National Project for Life-Time Commissioning and Energy Efficient Operation of Buildings. The goal of her work was data collection and the monitoring of demand control systems in the practice. Additionally, one of the aims of her work was the documentation of the real energy performance.

Technical data about the building, operation, and additional measurements are used to develop a procedure for LTC in this Master’s thesis. The procedures are developed specifically for the analyzed case buildings. All this information presents the building information from different phases of the building process. Demand specifications are retrieved from the idea phase, design parameters from the project phase, delivered values from the building phase, and operation values from operation and maintenance. The information is then used in the procedure to allow comparison of the values from the different phases and to ensure that the building owner’s demands are fulfilled with regard to the environment, energy, and resource use. These procedures are developed in Excel as rule-based

questions to allow for simple comparison and inspection. In addition, simulation programs are used to estimate the energy performance and to compare theoretical estimations with the measured energy use [17].

The introduced procedure seems to be working well, as several faults in different building systems are identified. A few faults are identified in the VAV system, such as the installed VAV-dampers having improper working conditions, a large difference between the measured and designed inlet air pressure, and a set point for the CO2 sensors is 1250 ppm, which is too high. Related to the lighting system, it is discovered that the installed lighting effect is much higher than recommended; therefore, the indoor air temperature is higher than recommended.An assessment of the indoor environment is performed by using both a survey among the building occupants and direct measurements. The results show that the measured indoor climate conditions are as demanded from Labor inspections, and the users seem to be happy with their environment according to the questionnaire responses. The noise from the dampers is not acceptable according to the supplier, and a replacement of the damper was recommended. An analysis of the CO2 level in the offices is shown in Figure 9. Regarding the current energy use in the analyzed office building, it is found that the

Figure 9. Analysis of CO2 level

in six different offices in one office building

.. the installed VAV-dampers having improper working conditions, a large difference between the measured and designed inlet air pressure, and a set point for the CO

2 sensors

is 1250 ppm, which is too high.

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total specific measured energy use is 189 kWh/m2, which is higher than the expected energy use of 130 kWh/m2. A possible reason for this difference is the effect caused by the high installed lighting effect. Currently, the specific energy use for lighting is 28 kWh/m2, which is much higher that the technical requirement of 8 kWh/m2 [17].

6.4. Documentation of an office building with a focus on upcoming energy requirementsLinn Dalaker’s project assignment and Master’s thesis were both within the National Project for Life-Time Commissioning and Energy Efficient Operation of Buildings. The title of this Master’s thesis is An office building with a focus on upcoming energy requirements. The subject is based on the adoption of EPBD and the effect on the Norwegian requirements regarding energy efficiency in buildings as a result of its adoption. These requirements have intensified and apply to the design phase as well as requiring documentation of the achieved results in the operation phase. In this thesis, the focus is on a new office building rented by a consulting engineering company. The office building is located in Oslo and was designed by the same consulting company that was tenant. The main requirement regarding the energy use of the building was that the building should be rated as a B energy class according to the adapted energy rating system. The main

Table 2. Mapping the Norwegian LTC procedures into the building lifetime

Part 1Framework for the commissioning project

Design Construction Operation

Requirements Part 2Performance

requirements in the design phase

Part 3Performance

requirements in the construction phase

Part 4Performance requirements

in the operation phase

Plan Part 5Plan for the Cx in the design phase

Part 6Plan for the Cx in the construction

phase

Part 7Plan for the Cx

in the operation phase

Common Part 8 and 9Performance requirements and description

objective of this thesis has been to follow-up on the operation of the building and document the achieved energy efficiency and indoor environment quality.

In this thesis, specific procedures for the following-up, testing, and verifying of the building performance are developed. Several deviations from the specific requirements are found by comparing building information in the design, construction, and operation phases. An earlier control process in the construction process could help to prevent several of the resulting problems. Inspection of the actual building energy use show that this building used 8 % more energy than calculated in the first year of operation. Inspection of the achieved indoor environment quality show that the temperature conditions are often not satisfied [18].

6.5. Norwegian lifetime commissioning proceduresThe Norwegian LTC procedures for improving building performance are developed based on international commissioning experiences and national practical experiences. The procedures are manual, consist of nine parts, and are available in Norwegian. The aim of the procedures is to create a good information system between all the participants during the lifetime of a building. According to the Norwegian LTC, commissioning work should be performed by a new role named Cx responsible. A Cx responsible is responsible for realizing the owner’s project requirements and providing a system for realizing the building performances through the building lifetime. The Cx responsible should provide the same services as a Cx authority in the ASHRAE Guideline 0-2005 [1]. Similarly, the Norwegian standard NS 3935, ITB Integrated technical building installations, Designing, implementation and commissioning[19], shows a need for an ITB responsible person. The LTC procedures consist of nine parts. These procedures are written for a generic project and have to be adapted for each LTC project. Table 2 maps the all nine parts in the building lifetime that consists of design, contraction, and operation phases. 

A Cx responsible is responsible for realizing the owner’s project requirements and providing a system for realizing the building performances through the building lifetime.

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A supervision plan based on the building owner requirements has to be established by using Part 1. In Table 2, Part 1 is in the left upper corner because it gives a framework for the activities defined in the other parts. Parts 2 and 5 correspond to each other. Similarly, parts 3 and 6, and parts 4 and 7 correspond to each other. For example, based on valid standards and the owner requirements, a list of requirements should be developed according to Part 2 in the design phase, and then according to Part 5 a plan for fulfillment of the requirements has to be given. Together with this inspection in the design phase (Parts 2 and 5), a list of necessary performance requirements has to be developed according to Part 8. According to Part 9, performance description has to start by developing early in the design phase. This performance description implies an actual performance follow-up defined according to Part 8. Parts 8 and 9 can be one document, but they are separated to make a clear difference between the performance requirements and the achieved performance in operation. As shown in Table 2, according to Parts 8 and 9, required information for these parts is necessary for the entire building lifetime.

How to collect data for LTC procedures? Practically, the necessary information for fulfillment of the LTC procedures can be collected in different ways. This case framework describes the building performance as a data model. The idea Figure 10. Framework for

collecting building performance

Element 1.1

Function 1.1.1

Function 1.1.2

Function 1.3.1

Function 1.3.2

Function 1.3.3

Measurement 1

Measurement 2

Measurement 3

Measurement 4

Measurement 5

Element 1.2

Element 1.3

Element 1

NS 3451

NS 3455Part 9

to collect building information as a data model came from NS 3451, Table of building elements [20], and NS 3455, Table for building functions [21]. Figure 10 shows an example of a generic framework on building performance. A building element can consist of a few sub-elements, which can be defined by a few functions. A function of a building element is a building performance. For example, a building element can be an air handling unit, which consists of few sub-elements such as the fan, filer, and heating and cooling coil. Additionally, the fan functions can include the air flow rate, pressure difference, motor power effect, and the specific fan power. The function numbers of an element depends on which performance data are necessary for performance estimation. The function numbers of an element depends on which performance data are necessary for performance estimation. As shown in Figure 10, the building elements should be defined according to NS 3451, while building performances are related to NS 3455. In that way, the documentation of Part 9, i.e., the performance description in Table 2, from the LTC procedures, can be established. To follow-up desired functions, it is necessary to the define measurement of that function, as shown in Figure 1. Therefore, the measurement of desired performances should be defined as soon as an element performance is involved in a building project.

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Figure 11. The first heat pump plant analyzed with the data fusion method

Figure 12. Direct and data fusion measurements of condenser heat

6.6. Data fusion heat pump performance estimationThe energy analysis of the case buildings inspired the development of a tool for advanced estimation of the heat pump performance. The case buildings will be briefly described in the section Building documentation for proper building maintenance. Data fusion is the process of combining data from different information sources to achieve better resulting information. By measuring the heat pump performance, compressor effect, and condenser heat, it was determined that the compressor effect was several times higher than the condenser heat. Theoretically, this ratio should be opposite. This created an idea to investigate more thoroughly what the reason for this could be. Therefore, the so-called improved measurements on heat pump performance were developed. This tool is developed in collaboration with our colleagues from the Polytechnic University of Hong Kong. In a later section, the method and need for such a method will be explained. To develop this method, it is necessary to have the plant documentation available and the possibility for good and detailed data logging. This method is presented for two case buildings for which much data and good BEMS were available for the analysis.

How does this method work? A model-based approach is combined with a data fusion technique to estimate performance of a heat pump. These improved heat pump performance measurements implied fused measurement between direct and indirect measurements of the compressor power and condenser load. Models for the compressor power and condenser load used input data from BEMS to produce measurements on the heat pump performance. The direct measurements are obtained by using the temperature and pressure measurements, while the indirect measurements are obtained using the electrical signal of the heat pump part load. The results showed a large need for the use of different data sources to define real energy performance metrics. Further, the analysis on the obtained measurements showed that indirect and fused measurements were more reliable than direct measurement alone, particularly

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for the condenser load. Measurement of the condenser load can be challenging in the case of a low temperature difference in the condenser. The use of only direct measurements could result in an estimation of electricity and heating energy consumption that is higher than the real consumption. The analysis of fused measurements on the heat pump performance showed that such an improved measurement could enhance the heat pump performance verification [22].

The first heat pump plant analyzed with the data fusion method is shown in Figure 11. The heat pump has two parallel compressor circuits. This heat pump is used as a heat pump during the winter for the ventilation system and as a cooling plant for the ventilation system in the summer. A small example of the heat pump performance estimation is shown in Figure 12. The estimations of the condenser heat calculated with the direct and fused method, along with the corresponding uncertainties, are presented in Figure 12.

Due to temperature sensors errors, the direct estimation of the condenser can be wrong, as shown with the blue line in Figure 12. Because the uncertainty of the fused measurement, the first from the bottom in Figure 12, is lower than the uncertainty of the direct measurement, the fused measurement is more reliable for further estimation and decision making. Next, we address whether the method is cost-effective or reasonable on any basis. By using an example from another case building, the necessity and cost-effectiveness of improved measurements is demonstrated. The schematic of the consumer substation in the case building located in Stavanger is shown in Figure 13. In this substation, the condenser heat from the heat pumps is used to support the space heating and ventilation heating needs. The heat pumps in Figure 13 are also the cooling plants installed for cooling the IT rooms. The plant shown in Figure 13 can provide exhaust air heat recovery in two ways: within the air handling unit and by using heat pumps.

Figure 13. Energy supply system in the office building in Stavanger

.. an improved measurement could enhance the heat pump performance verification.

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The aim of the analysis of the energy supply system in Figure 13 was to show the need for performance documentation, monitoring, and data integration during the lifetime of an energy system to achieve proper decision making. In the improved measurement approach the design, the manufacturer, and BEMS data are integrated. Direct and indirect measurements were combined into fused measurements. Two approaches are assessed for exhaust air heat recovery: within the air handling unit and by using heat pumps. The results showed that improved measurements are cost-effective and highly reliable for decision making. The results in Figure 14 give an example of how the direct measurements are unreliable. In Figure 14, it can be seen that the condenser load can be negative, which is impossible. Therefore, the use of the fused measurements is more reliable for decision-making, as shown in Figure 15 [23].

In Figure 15, the energy savings for different types of estimation methods are presented as a function of the ratio between the district heating and electricity price. By comparing different estimation methods, it is possible to identify the benefit of proper estimation. Actually, the financial benefit of the fused estimation is a proper knowledge of the real savings. If a wrong measurement were to be used, a wrong decision could be made [23].

6.7. Advanced analysis of measured data for efficient operation of modern buildingsFrançois Leboeuf, an exchange student from the University of Grenoble, France, researched both the project assignment and his Master’s thesis within this research project. The goal of his work was the advanced analysis of measured data. One of the aims of his project assignment is to build a strategy that enables the detection of sensor faults in a heat pump system. The most interesting results from Francois’s project assignment are briefly introduced here. The heat pump introduced in Figure 11 was analyzed in this project assignment.

Why is an advanced analysis method necessary for building operation? When a building operator takes a look at BEMS data of a building component, there are many available data

Figure 14. Poor heat pump performance estimation by using direct estimation

Figure 15. Financial benefit of fused measurements

Figure 16. Influencing variables on the heat pump performance

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to analyze, such as pressures, temperatures, control signals, etc. For a complicated plant such a heat pump, it can be difficult to make quick but reliable decisions. Therefore, to detect the sensors faults in the heat pump plant in this study, a statistical method named principal component analysis (PCA) is used. PCA is used when there are a large number of predictor variables, and those predictors are highly correlated or even collinear. For example, the performance of the heat pump is defined by the compressor suction and exhaust pressures, the evaporator and condenser temperatures, etc. In addition, these variables are correlated. In this complex problem, the PCA method can help by establishing a common variable that can show discrepancies in the system. This method is quite robust and is used extensively in the oil industry. The PCA method has been used for sensor fault detection in HVAC systems as well [3]. Before the method for detection of the sensor faults was established, the principal characteristics and physicals parameter important for the heat pump are reviewed. To properly analyze component faults, it is very important to first consider sensor faults [24].

By using PCA to analyze the heat pump, it is possible to identify the important influencing variables. In Figure 16, the importance of the different variables is presented. The importance of variables is measured by the size of the variable contributions to principle components (PC). In Figure 16, it is possible to notice that the suction pressures and outdoor air temperature are important variables for the heat pump performance. The means that a large deviation of these variables is necessary to detect a sensor fault. However, a small sensor fault in the condenser temperature measurement can be easily detected because the contributions of the condensed temperatures have a smaller effect on the PCs. The results in Figure 16 show that an acceptable level of a fault is not the same for different sensors [24]. To prove the robustness of the PCA method for sensor fault detection and the discussion from Figure 16, tests are conducted by introducing sensor faults for temperature measurements. In Figure 17, X-residuals are shown when a 20 % deviation is introduced for the temperature sensor. The X-residual has a high value when a temperature sensor has a deviation of 20 % (see the middle of Figure 17). The results show that it is possible to detect sensor faults and to isolate which sensor is involved [24].

Figure 17. 20 % faulty measurement of temperature sensor

.. to detect the sensors faults in the heat pump plant in this study, a statistical method named principal component analysis (PCA) is used.

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6.8. Building documentation for proper building maintenanceThe Norwegian LTC procedures, explained in Section 6.5, were tested on two office buildings in Stavanger and Trondheim. The aim of this project was to find out how these procedures work in the current practice and to prove the benefit of the gained knowledge by collecting the building information for the LTC procedures. The partners Statoil and GK Norge AS suggested their projects as the case buildings. The two case buildings are rented as office buildings. These building and the most important findings are briefly described below.

The first case building, with 19 623 m2 of heated area, as shown in Figure 18, is located in Stavanger, where the design outdoor temperature is -9 °C, while the average annual outdoor temperature is 7.5 °C. This first case building is designed for 1 200 users and has been in use since June of 2008. Our research on the case building in Stavanger started after the building was occupied. The second case building, with 16 200 m2 of heated area, as shown in Figure 19, is located in Trondheim, where design outdoor temperature is -19 °C, while the average annual outdoor temperature is 6 °C. The second case building has been in use since September 2009 and the number of users has been increasing since that time [25]. Our research and data collection related to the office building in Trondheim started before the construction phase. The ventilation systems are different in these buildings, while the energy supply systems are similar. In the first case building, the ventilation system consists of three VAV systems, in which the maximal air volume is 90 000 m3/h for two of the ventilation systems and 75 000 m3/h for the third system. In the second case building, the ventilation system consists of eight VAV systems, with the maximal air volume ranging from 12 500 m3/h to 22 000 m3/h. In both case buildings, heating is provided by radiators, while cooling is provided by fan-coils. The heating energy for ventilation, space heating, and domestic hot water is supplied by district heating and heat pumps. Cooling energy is supplied by two cooling plants. Heat produced from the cooling plant condensers is used as additional energy for heating. In that way these cooling devices are, at the same time, heat pumps. The only difference between the heat supply solutions in these buildings is that in the second case building, one cooling plant is only used for the ventilation systems, while the second cooling plant is used for fan-coils. In the first case study, two of the cooling plants are supposed to work cooperatively [25]. The energy supply system in the first case building is explained in the second part of Section 6.6. One of the heat pumps in the second case building is shown and analyzed in Sections 6.6 and 6.7. Using the LTC procedures, several common findings were discovered in the two case

Figure 19. Office building in Trondheim

Figure 18. Office building in Stavanger

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studies: a lack of documentation, system oversizing due to a lack of information, poor functional definition, and poor functional integration. Poor functional integration means that the temperature sensors in the ventilation systems were related to the wrong temperature measuring points. Further, the ventilation systems are well documented and satisfied the requirements in both buildings. However, there is a lack in documentation related to hydronic systems, such as the domestic hot tap water system, the hydronic heating system, the fan-coil system, and the cooling systems. Therefore, an energy audit, inspection, or testing of these systems could be difficult. In total, approximately 20 % of all the defined building performance data can be monitored by BEMS [25].

The most important findings related to the first case building located in Stavanger (Figure 18) are the following:• The installed fans in the ventilation system satisfied the requirements;• Electricity use takes the largest share in the total building energy use: approximately 70 – 80 %. At the same time, the electricity use does not vary so much over the year;• In the design phase, the idea was to utilize heat recovery from the exhaust air with the heat pump for the building’s energy supply. In that case, the heat pump plant could cover the entire heating energy demand in the building. However, the ventilation systems were installed with the heat recovery system from the exhaust air. This change from the design idea caused a few problems in the plant operation. The heat pump plant is oversized and therefore one of the installed heat pumps is shut down most of the time. The additional heat exchangers and corresponding control valves for the ventilation system are oversized. Therefore, the valve positions and operation time are low, which is negative for their operation. The entire analysis is described in other works [23, 26].

The most important findings related to the second case building located in Trondheim, Figure 19, are the following:• The installed ventilation system satisfied the requirements in the design, takeover, and operation phase;

• The optimal fan control strategy of the VAV system induces a low electricity energy use for the fans in comparison to the total electricity use;• By using the data fusion method explained in Section 6.6 and the PCA method explained in Section 6.7, several faults related to the heat pump in Figure 11 were identified, including a poor energy monitoring of the heat pump and abnormal pressure measurements;• A cooling system was designed with a cooling demand of 60 – 200 kW. Consequently, a cooling plant with R-410A as the working fluid was installed. Utilization of the condenser heat from this cooling plant could cover 23 – 70 % of the total building heating demand. However, in the first year of operation, it was not possible to obtain useful condenser heat due to the low evaporator load and because R-410A is not intended to operate under high condensation temperatures;• The building is equipped with 74 energy meters, in which 66 of the meters are for electricity and eight meters are for heating and cooling measurements. The biggest failure in the energy measurement was due to lost data, approximately 20 % in the first operation year. Although the energy measurement data were repaired by using the neural network method, there was still a failure of 8 - 24 % compared to the energy measurement of the energy supplier company. Sub-meters for the hydronic system had the biggest failure.• The total electricity use did not increase very much, even though the number of users increased from 172 to 299 during 2010 [27].

Finally, a general conclusion from both case studies is that well-documented systems perform well, while systems with a lack of documentation do not perform well. This supports our project idea that detailed documentation and good monitoring are crucial for proper plant operation. Although a lack in documentation has been reported in these two case studies, the amount of information collected here is still large compared to the current practice. The reason for this was the awareness and eagerness of our partner to support the project.

.. 20 % of all the defined building performance data can be monitored ..

The biggest failure in the energy measurement was due to lost data ..

.. well-documented systems perform well, while systems with a lack of documentation do not perform well ..

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6.9. PFK-webBuilding projects are often characterized by extreme complexity, alterations during construction, and non-standardized production. Each project is planned and performed to meet the project requirements. Therefore, the utilization of previous experience is very important for building projects. For the success of a new project, the experience from previous similar projects can be of great importance, as that experience can contribute significantly to achieving the objectives such as cost, appointed schedule, quality, and safety. Further, the transfer of experience can also help prevent the invention of already solved problems. For the better transfer of experience and information and for the automation of quality assurance in the building process, we created a tool that can aid in this area. The tool is based on the Norwegian lifetime commissioning procedures introduced in Section 6.5 and is named PFK-web [28] for the Norwegian abbreviation for the project title.

PFK-web is a database for the documentation and quality assurance of a building process, developed by Norconsult, which is a former Pro Technology in collaboration with NTNU/SINTEF Energy. The database is intended to make the building lifetime commissioning process easier in practice. PFK-web is a database tool developed in Structured Query language (SQL), a programming language designed to organize data in a relational database. PFK-web has a web-based user interface that enables the tool to be used from multiple computers and locations simultaneously. Further, this tool can be used in a building’s planning, construction, and operation phases. PFK-web contains guidance for the implementation of various checkpoints for a current project. This is advantageous when compared to traditional manual checklists, in which the same lists were used in several projects without considering their relevance. PFK-web can have multiple users; each user is assigned a role with its possibilities and limitations, and the role can vary from a constructor role, Cx responsible, project owner, or possibly only read-only access to PFK-web.

How does PFK-web work? A registered user creates the project and associated project information that is relevant for a current project. The start-page of PFK-web is shown in Figure 20. To create a project, a set of building phases can be selected. During the project creation in PFK-web, a set of phases can be selected. The phase may be an early design, sketch, detailed, construction, or operational phase. These building phases have a set of standard information such as room types, system types, checklists, etc. When the project is completely created, a user will have access to further information. PFK-web offers opportunity to include new checkpoints. The checkpoints are linked to the checklists related to three different levels: 1. Checkpoints related to different building phases 2. Checkpoints related to different room types 3. Checkpoints related to different building service systems

The examples of the general checkpoints related to the room types can be: U-values of walls or if the doors are adjusted for handicapped persons. In a further phase, the checkpoint related to the room type can be about floor slope or if the water lock is properly installed. The system checkpoints are related to the systems in the buildings and they can include questions such as if the ventilation air intake is properly sized. One system that serves several rooms is linked to them accordingly in the database. Rooms and systems have associated attributes that are related to the different building project phases. Room attributes include room size, internal heat loads of the occupants, etc. System attributes include the air flow rate in the ventilation system or the installed capacity of the heating system. The project checkpoints that have been accepted are clearly visible in the PFK-web start-page, as shown in Figure 20 in green. Here, it is simple to identify how much of the project was done and what has been accepted. However, it is not easy to find the executed project checkpoints. Therefore, a further step in the database to the System/Accepted quality should be made as shown

.. experience can contribute significantly to achieving the objectives such as cost, appointed schedule, quality, and safety.

PFK-web is a database for the documentation and quality assurance of a building process ..

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in Figure 21, where the checkpoints are organized by the building phase, building part, location, block, and associated system. The history and tracking of changes will be stored so that it is always possible to have overview of the accepted checkpoints. All the checkpoints will also have an

additional column that is accessible only for the Cx responsible. In that column, the Cx responsible can mark all disagreements with “Not OK” and give comments. Finally, it is simple to create a report that includes the checkpoints and associated quality control.

Figure 21. Checklist report

Figure 20. Start-page of PFK-web

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Looking back on the participation in the PFK project from one of the participants Terje Åsberg - Statsbygg (Public sector Administration Company for public construction and property management)

Why did I join the project?

As a young researcher in the 1970s at Byggforsk, the former Norwegian Building Research Institute (NBI), I realized that there were large and significant shortcomings at the takeover of new buildings. In collaboration with all the Nordic building research institutes, we developed and tested methods and procedures (planning, design, construction, installation, adjustment, etc.,) to help ensure that the end result was the best possible. It was also important that the finished building could be measured, controlled, and documented. We produced various joint Nordic methods and guidelines. Among other things, I initiated Norwegian ventilation control, which I also led. In addition, I was the specialist who was visited and controlled the plants. This was a very interesting and instructive period for a young engineer.

I did this on the active bases for 15 years from 1970 and made the following general observations:

• There was a lack of knowledge about the monitoring and coordination of the construction process, especially ignorance about measurement, controls, and documentation in the final stages of construction projects. The actors / participants from the industry failed to see the whole.

7. Necessity and importance of lifetime commissioning in Norwegian industry

• There was great reluctance in the industry to implement any form of control, including assembly control, performance control, functional control, documentation control, etc.• There was no systematic, consistent method or tool for quality assurance, i.e., quality management and quality control in the construction project. There was no method to ensure that the client’s needs (in the space and building program) were met, safeguarded and controlled at all stages, nor to document that what was ordered was delivered.

What benefit did I see in the project?

When NTNU and SINTEF asked if I would participate in the PFK project, I was extremely excited about getting the opportunity to help with the use of my experiences. I had also made a quality assurance handbook for construction projects with the support of Byggforsk that was funded by the Norwegian Research Council. In addition, I had 15 years of experience in client operations and management, even including the control of finished buildings and experience from the operation of new buildings. I must admit that I am disappointed that we have not come further than where we were many years ago! There is still little or no consistent commissioning, and very inadequate documentation from adjustments and tuning, and controls and deliverables, i.e., O & M documentation.

My participation in the PFK project has been enlightening. Many knowledgeable people have participated in the project. The project spans multiple contexts, such as lectures and

There was a lack of knowledge about the monitoring and coordination of the construction process ..

My participation in the PFK project has been enlightening.

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seminars for industry, and helped to explain the necessity of having a comprehensive quality assurance system for construction projects. Quality control or function must be implemented in all phases. The methods with tutorials, schematics, etc., that the PFK project has prepared for all of the phases of the construction process is a very good guide for students, project managers, and the entire industry. It is crucial in any construction project process to use digital monitoring and recording systems so you can easily store and retrieve necessary information.

The benefits of the PFK project are:

• A thorough, systematic method that shows how the quality assurance will be described and implemented in construction projects. This is important for all parties, especially the project managers.• There is advice on the various technical assessments which must be taken in all phases. This is particularly important for the technical professional participants in the projects.• There is a procedure for how the final checks shall be performed to demonstrate that the final product (the structure and equipment) is in accordance with the original needs and performance requirements and functions. This is especially important for the building owner.• There is a database that contains all the necessary O & M documentation. This is useful for property managers and particularly for operating personnel.

Quality control or function must be implemented in all phases.

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The publications made during this project are listed here.PhD thesis1. N. Djuric, Real-time supervision of building HVAC system performance, 2008.2. M. Masic, Using building energy monitoring to verify building energy performance, 2009.

Master theses and project assignments1. A. Eide, Demand control of energy and indoor environment performances - a case study, Project assignment and Master thesis, 2009.2. L. Dalaker, An office building with a focus on upcoming energy requirements, Project assignment and Master thesis, 2009.3. F. Leboeuf, Advanced analysis of measured data for efficient operation of modern buildings, Project assignment and Master thesis, 2010.4. J. Wall, Lifetime commissioning database for better quality control of modern buildings, Project assignment, 2012

Journal articles:1. N. Djuric, V. Novakovic, F. Frydenlund, Electricity use in two low energy office buildings in Norway, REHVA European HVAC Journal. 2012; Volume 49 (1). S. 30-34.2. N. Djuric, V. Novakovic, F. Frydenlund, Frode, Improved measurements for better decision on heat recovery solutions with heat pumps, International journal of refrigeration. 2012; Volume 35 (6). S. 1558-1569.3. N. Djuric, V. Novakovic, G. Huang, Lifetime commissioning as a tool to achieve energy-efficient solutions, International journal of energy research, 2012; Volume 36 (9). S. 987-999.4. N. Djuric, G. Huang, V. Novakovic, Data fusion heat pump performance estimation, Energy and Buildings, 2011; Volume 43 (2-3). S. 621-630.5. N. Djuric, V. Novakovic, Correlation between standards and the lifetime commissioning, Energy and Buildings, 2010; Volume 42 (4). S. 510-521.6. N. Djuric, V. Novakovic, Review of possibilities and necessities for building lifetime commissioning, Renewable & sustainable energy reviews, 2009, Volume 13 (2). S. 486-492.7. N. Djuric, V. Novakovic, F. Frydenlund, Heating system performance estimation using optimization tool and BEMS data, Energy and Buildings. 2008; Volume 40 (8). S. 1367-1376.8. N. Djuric, V. Novakovic, J. N. Holst, Z. Mitrovic, Optimization of energy consumption in buildings with hydronic heatingsystems considering thermal comfort by use of computer-based tools, Energy and Buildings. 2007; Volume 39 (4). S. 471-477.

Conference articles1. N. Djuric, V. Novakovic, F. Frydenlund, B. Handal, Lifetime Commissioning as a Tool for Improving Heat Recovery Using Heat Pumps, Proceedings of the 23rd International Congress of Refrigeration. International Institute of Refrigeration, Prague, Czech Republic, 2011.2. N. Djuric, V. Novakovic, Lifetime Commissioning as a Tool to Achieve Efficient Building Operation, 41st International congress on Heating, refrigerating and air- conditioning, Belgrade, Serbia, 2010.3. M. Lalovic, N. Djuric, V. Novakovic, B. Zivkovic, Assessment of Risk of Increased Energy Consumption due to climate change and change of building purpose, 41st International congress on Heating, refrigerating and air-conditioning, Belgrade, Serbia, 2010.4. M. Masic, V. Novakovic, Tool for Modeling and Analysis of Building Heat Consumption, 41st International Congress on Heating, Refrigerating and Air-Conditioning, Belgrade, Serbia, 2010.5. N. Djuric, V. Novakovic, F. Frydenlund, Test Results of Norwegian Lifetime Commissioning Procedures. 10th REHVA World Congress “Sustainable Energy Use in Buildings”; Antalya, Turkey, 2010.6. N. Djuric, V. Novakovic, Efficient Building Operation as a Tool to Achieve Zero Emission Building, Renewable Energy Research Conference 2010 - Zero Emission Buildings, Trondheim, Norway, 2010.7. N. Djuric, V. Novakovic, FDD algorithm for an AHU reverse-return system. 8th International Conference for Enhanced Building Operation – ICEBO 2008, Berlin, Germany, 2008.8. N. Djuric, V. Novakovic, F. Frydenlund, Existing building commissioning using computer based tools. The 9th REHVA World Congress - Clima 2007, Helsinki, Finland, 2007.9. N. Djuric, F. Frydenlund, V. Novakovic, J. Holst, Preliminary Step in Collecting Data for Commissioning of Existing Buildings (Characterization of buildings, systems and problems), The 9th REHVA World Congress - Clima 2007, Helsinki, Finland, 2007.10. V. Novakovic, A standard methodology for building energy consumption data investigation and description. The Sixth International Conference on Indoor Air Quality, Ventilation & Energy Conservation in Buildings – IAQVEC, Sendai, Japan, 2007.11. N. Djuric, V. Novakovic, J. N. Holst, Optimizing the building envelope and HVAC system for an inpatient room by using simulation and optimization tools. The 5th International Conference on Cold Climate Heating, Ventilation and Air-Conditioning, Moscow, Russia, 2006.12. V. Novakovic, N. Djuric, J. N. Holst, F. Frydenlund, Norwegian national program for lifetime commissioning and energy efficient operation of buildings. The 6th International Conference for Enhanced Building Operation – ICEBO 2006, Shenzhen, China 2006.13. N. Djuric, V. Novakovic, J. N. Holst, Optimization of Energy Consumption in Building with Hydronic Heating System by use of Computer based tools. The 8th REHVA World Congress - Clima 2005, Lausanne, Switzerland, 2005.14. V. Novakovic, J. N. Holst, T. Hoel, Lifetime commissioning for energy efficient operation of buildings - Norwegian approach. The 8th REHVA World Congress - Clima 2005, Lausanne, Switzerland, 2005.15. V. Novakovic, J. N. Holst, The building envelope and HVAC system for an inpatient room using simulation and optimization tools. The 2005 World Sustainable Building Conference, Tokyo, Japan, 2005.16. N. Djuric, V. Novakovic V., J. Holst, Optimization of the design for an inpatient room using simulation and optimization tools, Proceedings of 36th congress of Air – conditioning, Heating and Refrigeration – KGH (in Serbian), Belgrade, Serbia, 2005.

Technical publications1. N. Djuric, V. Novakovic, F. Frydenlund, Funksjonskontroll som verktøy, Norsk VVS, 2010.2. N. Djuric, Lifetime commissioning report at Professor Brochs gate 2. Vol. TR A7098. 2011, SINTEF Energy.3. N. Djuric, Lifetime commissioning report at Vassbotnen 23. Vol. TR A7094. 2011, SINTEF Energy.4. T. Wigenstad, Lifetime commissioning – procedures for requirement specification - draft, AN 09.16.08, SINTEF Energy

8. Scientific and technical publications

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[1] ASHRAE Guideline 0-2005: The Commissioning Process, 2005: The American Society of Heating, Refrigerating and Air-Conditioning Engineers, Atlanta, US. ISBN/ ISSN: 1049-894X[2] P. Haves, D. Claridge, M. Lui, Report assessing the limitations of EnergPlus and SEAP with options for overcoming those limitations, 2001, California Energy Commission Public Interest energy Research Program.[3] S. Wang,F. Xiao, AHU sensor fault diagnosis using principal component analysis method. Energy and Buildings, 2004. 36(2): p. 147-160.[4] J. Hyvarinen, S. Karki (Eds), Building Optimization and Fault Diagnosis Source Book, 1996, IEA Annex 25, VTT, Finland.[5] ASHRAE HandbookCD, 2000-2003, ASHRAE.[6] H. Friedman,M.A. Piette, Comparative Guide to Emerging Diagnostic Tools for Large Commercial HVAC Systems, 2001, Ernest Orlando Lawrence Berkeley National Laboratory.[7] T.I. Salsbury,R.C. Diamond. Model – Based Diagnostics for Air Handling Units. in Diagnostics for Commercial Buildings: Research to Practice. 1999. San Francisco.[8] IEA Energy conservation in Building and Community Systems. Available from: http://www.ecbcs.org/.[9] IEA - ECBCS Annex 47 Cost-effective Commissioning for Existing and Low Energy Buildings Available from: http://ctec-varennes.rncan.gc.ca/en/b_b/bi_ib/annex47/ index.html#.[10] Annex 53 - Total Energy Use in Buildings: Analysis and Evaluation Methods. Available from: http://www.ecbcs.org/annexes/annex53.htm.[11] C. Legris, N. Milesi Ferretti, D.E. Choinière, Commissioning overview, Annex 47 Report 1, 2010.[12] Natural Resources Canada, Canmet Energy Technology Center. [cited October 2012; Available from: http://canmetenergy.nrcan.gc.ca/buildings-communities/ energy-efficient%20buildings/optimization/1772.[13] Continuous Commissioning. [cited October 2012; Available from: http://esl.tamu.edu/continuous-commissioning.[14] N. Djuric, Real-time supervision of building HVAC system performance. Vol. 2008:159. 2008, Trondheim: Norwegian University of Science and Technology, Faculty of Engineering Science and Technology, Department of Energy and Process Technology. p. 135, 978-82-471-9287-0[15] MATLAB, 2010, The MathWorks.[16] M. Masic, Using building energy monitoring to verify building energy performance, 2009, Trondheim: Norwegian University of Science and Technology, Faculty of Engineering Science and Technology, Department of Energy and Process Technology, p. X, 139, LXXXVIII s, 978-82-471-1873-3[17] A. Eide, Demand control of energy and indoor environment performances - a case study, in Department of Energy and Process Engineering2009, Norwegian Universtity of Science and Technology, Faculty of Engineering Science and Technology: Trondheim.[18] L. Dalaker, An office building with a focus on upcoming energy requirements, in Department of Energy and Process Engineering2009, Norwegian Universtity of Science and Technology, Faculty of Engineering Science and Technology: Trondheim.[19] NS 3935, ITB, Integrated technical building installations, Designing, implementation and commissioning, Standard Norway, Editor 2005.[20] NS 3451, Table of building elements, Standards Norway, Editor 2009.[21] NS 3455, Table for building functions, Standards Norway, Editor 1993.22] N. Djuric, G. Huang, V. Novakovic, Data fusion heat pump performance estimation. Energy and Buildings. 43(2-3): p. 621-630.[23] N. Djuric, V. Novakovic, F. Frydenlund, Improved measurements for better decision on heat recovery solutions with heat pumps. International Journal of Refrigeration, 2012. 35(6): p. 1558-1569.[24] F. Leboeuf, Advanced analysis of measured data for efficient operation of modern buildings, in Faculty of Engineering Science and Technology, Department of Energy and Process Engineering2010, Norwegian University of Science and Technology.[25] N. Djuric, V. Novakovic, G. Huang, Lifetime commissioning as a tool to achieve energy-efficient solutions. International Journal of Energy Research, 2012. 36(9): p. 987-999.[26] N. Djuric, Lifetime commissioning report at Vassbotnen 23. Vol. TR A7094. 2011, Trondheim: SINTEF Energy Research. p 48, [28] bl. : ill., 978-82-594-3474-6[27] N. Djuric, Lifetime commissioning report at Professor Brochs gate 2. Vol. TR A7098. 2011, Trondheim: SINTEF Energy Research. p 49, [43] bl. : ill., 978-82-594-3476-0[28] J. Wall, Lifetime commissioning database for better quality control of modern buildings, in Faculty of Engineering Science and Technology, Department of Energy and Process Engineering2012, Norwegian University of Science and Technology.

9. References

Page 32: Natasa Nord Vojislav Novakovic - SINTEF...1 1. Aim and scope of the project The main goal of this project was to develop, verify, and implement suitable tools for estimating building

This book is intended for building owners, project leaders, designers, contractors, opera-tion and maintenance services, suppliers of building automation systems, and building authorities. It addresses topics that are interest-ing to all stakeholders focused on achieving significant and documented energy savings in place of simply using an intuitive approach. The book is written in a simple and descriptive way for a wide group of users.

The background for this book came from the results obtained through the National Project for Lifetime Commissioning and Energy Efficient Operation of Buildings (PFK). The project has lasted for eight years, and the last six were supported by the Norwegian Research Council. Seven industrial partners have been involved in the project through the eight years. The project

partners were the property owners, contractors, a national agency promoting increased sustain-ability in energy consumption and generation, and a consulting company. The partners contributed with their experience, practical challenges, and case studies. We highly appreci-ate and thus would like to thank them for their valuable contributions.

Through the project lifetime, we have contribut-ed to two international projects under the International Energy Agency (IEA) Energy Conservation in Buildings and Community Systems (ECBCS) Programme: Annex 47 and Annex 53. In this way, international experiences and ideas have been transferred into this national project. During this project, two PhD theses, three master’s theses, and more than 20 journal and conference articles have been published.