1. Case Study: Operations and Maintenance Report applied to a sample of buildings

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1 1. Case Study: Operations and Maintenance Report applied to a sample of buildings 1.1. In 2009 SEAI set up a special working group to assess the potential for energy improvements in the commercial buildings sector. One of the key concerns raised by the participants of the working group was the absence of an easy to read and understand user guide to the area of operations and maintenance practices for commercial buildings with regard to energy consumption. SEAI commissioned the writing of commercial building operations and maintenance user guide and the working group then decided to have its usefulness assessed. To assess its usefulness SEAI decided to carry out a number of assessments on some commercial buildings using the guide and this case study is undertaken to pass on some of the learning from this work. One of the clear observations from the work was that whereas in discussions related to facilities and energy we typically refer to operations and maintenance in the same sentence, and it is typically taken as read that the maintenance personnel will operate the commercial building to its best potential. It is also however patently clear that maintenance personnel, typically outsourced manpower, and almost always responsible for multiple buildings and systems do not have any strong linkage to the core function of the building. Maintenance of the building is typically the responsibility of a company under contract to the building owner/ occupier, and whose main responsibility is to ensure that building services are maintained. It is quite common that this company does not have a responsibility for energy budgets, and indeed typically has a limited interface with the building function. The people with a real impact on the buildings operations are the key users of the building as these are the persons that through their scheduling of work, order processing and other uses of the building really determine the requirements for services within the building. It is common that these persons do not view energy as being under their remit. Occurrences observed on a number of the sample sites visited included: No strong link between start times of building services equipment, building occupation times and the time taken to heat up/ cool down the building. 1

2 No definitive requirements for services, eg temperature and humidity within spaces. (keep it comfortable what is comfortable?, to ensure that equipment does not overheat what are the temperature limits to prevent this occurrence?) It is suggested that the operations of a buildings services should rest with the building user insofar as the building owner/ user should take some responsibility for addressing or at least assessing the appropriateness of the times of activities of a building, the service specification (eg temperature, humidity, times for starting, stopping, set back etc) Maintenance is typically seen as an activity related to ensuring that the equipment is capable of operating to perform its stated functions and to limit the risk of failure thus ensuring its reliability Another feature that raises its head in respect to commercial buildings is the concept of an automatically operated suite of services the background services just operate, controlled by some magic background controller that maintains personnel comfort and all other requirements. The ideal situation, surely!, the evidence suggests otherwise. It was observed that where buildings were controlled by state of the art Building Management Systems, (BMS), and there was no one resident on site from a building operations perspective with an understanding of how the system operated, and maintenance personnel kept the system working, led to some basic observations. 1. It was not unusual to find equipment central to the core function of the building, such as photocopiers, printers, fax machines etc., were operated just below the temperature sensors for the temperature in open plan office spaces. This of course led to overcooling of the air coming from the centralised HVAC system, and subsequent reheating of the air feeding into parts of the space that the temperature sensors were not fooled by fax machines and printers etc. This also led to dissatisfaction among office space occupiers about draughts from the HVAC due to the differing air temperatures of air fed to the room. This diagram shows the electrical usage on site versus cooling degree days with a base temperature of 6.5 degrees. Essentially the analysis of the electrical consumption against weather showed that there was no relationship on this site between outside 2

3 temperature conditions and electrical consumption, despite the fact that the largest user of electricity on site per year was the chiller plant and the requirement was for simple temperature comfort conditions without humidity control. This plant had a number of areas where photocopiers were controlling the chiller plant loading. 2. It was observed in a number of locations that the building services start and stop times did not appear to match the real building temperature trends which suggested that there were some other hidden start functions coming into play. This building apparently had its heating and cooling systems switched off at 1700 hrs each evening and back on again at 0600 the next day It was noted that across the board, where new projects have been undertaken, or where alterations have been made to commercial buildings, energy seems to be relatively central to the decisions made in relation to services etc. This has led to the use of improved technology and better services in the form of better BMS control, more efficient boilers, etc. The area that has room for improvement is in the provision of information to users and maintainers as to the best ways to operate the services, limitations, linkages with other equipment or services etc. A number of examples of improved operational control was seen through the improved use of maintenance personnel. In a number of cases, maintenance personnel are tasked centrally to carry out an energy walk-through of a building specifically to look for energy opportunities related to operations of the building as well as technical issues. This would include offices heated and cooled where offices are unused temporarily, assessment of operation hours of equipment versus building occupation hours, cassette air handling units in use within offices in automatic (heating and cooling) mode, where radiators remain on, shifts not overlapping where they could which would allow reduced hours of building use. The best examples of this were seen where the maintenance persons had an interactive working relationship with building owners/ operators, and would discuss the building services openly between 3

4 them in relation to energy consumption as well as reliability. Places where the maintenance and operations personnel had full access and knowledge of energy bills for their buildings were the places where best results were seen. Commercial building owners appear are becoming more aware of the various information that is now aware from their energy suppliers in relation to electricity supplies, but it is not always the case that this information is fully assessed to try to identify the drivers in consumption to allow more targeted energy programs. Similarly for natural gas supplies, the figures tend only to be considered on a monthly billing basis and building owners tend to overlook the potential for improved knowledge that exists in the daily gas consumption information that is typically attached to a large gas users bill. Simple analysis of the energy data against hours of operation, shift, days of week is relatively simple. Some building owners do not carry out weather assessments due to the lack of meteorological data on site. Some were unaware of the various free sources of degree day analysis information that is freely available on the web that would allow them to improve their energy assessments. As with any commercial environment, improvements in energy performance needs to be verifiable to ensure that funds remain available for further improvements. In discussions with the various building owners taking part in this review, the difficulty really appears to occur in sites where energy consumption has gone up after energy improvements due to other changes that people have overlooked. For this reason Verification of energy savings is vital. The key factor in successful measurement and verification activities is where sufficient data is available before project implementation to allow the generation of a baseline, and an agreed mechanism for verification developed before the project is started. It always requires some consideration to the fact hat sometimes energy savings projects do not perform as expects, generally due to misunderstandings in the energy savings assessments proceedings. Low cost energy savings potential exists in commercial buildings, most often in relation to changes in operations practices as opposed to technical changes. This requires a positive attitude to change with all building stakeholders and a positive attitude to energy also, where it is not looked at as someone else s problem, Maintenance personnel can have a key input where they can be a fresh pair of eyes looking at the buildings functionality and assessing its efficiency of use. This will only work where maintenance personnel are encouraged to feel free to question anything in relation to both operations and maintenance practices however big or small. 4

5 It may prove more difficult to get this desired outcome to work in situations where building maintenance is outsourced to external companies and the competitive nature of the tender system lends itself to minimum maintenance staff to carry out required tasks and lack of resource availability does not lend itself to spending time assessing a buildings energy consumption where the facilities management company has no responsibility for the energy bill. Commercial building owners who outsource building and building services maintenance functions need to take cognisance of this at the contract stage and ensure that they have some performance metrics in relation to energy consumption as well as reliability. This is to ensure that energy remains a key priority item to all stakeholders of which the facilities management company is one. 5