Application and management of environmental technologies in UK schools: A case study

Transcription

1 SET211, 1 th International Conference on Sustainable Energy Technologies, İstanbul, TÜRKİYE, 4-7 Sep. 211 Application and management of environmental technologies in UK schools: A case study Masoud Malekzadeh 1, Dino Bouchlaghem 1, Andrea Wheeler 1 1 Department of Civil and Building engineering, Loughborough University, UK Abstract This paper presents some of the preliminary results from a study investigating the extent and causes of the discrepancies reported in the literature (e.g. [1], [2] and [3]) between computer-based predicted performance of buildings during design and their actual in-use performance using a number of case study buildings. A post-occupancy evaluation and performance assessment approach is used for the case studies in the form of measurement-based performance monitoring, user surveys, and the review of historical records of information from the design and construction phases of the projects considered. The project aims to provide a set of guidelines to be used by designers as decision support and by simulation tools developers to further improve the accuracy of their models in real life performance prediction. All the case studies in this research are school buildings designed and built in compliance with the most recent British and European building regulations (for example [4]). In order to meet the standards imposed by these regulations and minimise the consumption and pollution level from the new buildings, a number of new technologies have been used in these schools, some of them tried for the first time in a school building. In many cases, the inclusion of these new technologies means higher capital costs in the projects, which is not always affordable by public authorities, unless they are funded under the PFI scheme. Private Finance Initiatives (PFIs) are a form of public/private partnership introduced in the UK in 1992 where a private consortium provides the funding for the design and delivery of the project for a predefined re-payment scheme from the Government. PFIs are often (although not exclusively) used for the procurement of construction projects such as hospitals, roads and schools [5]. They usually involve a long-term commitment from the consortium to operate and maintain the buildings for a period of usually 15-3 years after construction, with the consortium paid back in instalments conditional on performance. On expiry of the contract, ownership of the project s assets usually reverts back to the public sector. Therefore, a study on the divergence between predicted benefits of the aforementioned low carbon technologies and their actual performance needs to consider the role of all stakeholders including designers, builders, managers and users as well as relationships between and coordination among the four groups. This paper reports on findings concerning the impact of each of the main stages of a project s life cycle and those involved in them on the overall performance of the case studies. The paper also emphasizes on the importance of communication and cooperation between the four stakeholder groups (at least for the first few years of the utilisation of the building) as a key to the success of the systems as designed. Evidence of under-utilised features or systems is presented and their potential effect on buildings performance is estimated. Keywords: prediction, simulation, POE, PFI, BSF, management, low carbon technologies 1. Introduction Although there seems to be no widely accepted standards or metrics for defining a sustainable school building [6], government s Sustainable Schools National Framework provides The Children s Plan [7] that introduces eight doorways (food and drink, energy and water, travel and traffic, purchasing and waste, building and grounds, inclusion and participation, local well-being, and the global dimension) as a framework for engaging with sustainability. Comparing these doorways with the pointers offered by the Building Research Establishment s Environmental Assessment Method (or BREEAM) [8] for the assessment of buildings (which assign points for management, health and well-being, energy use, transport, water, materials, land use and ecology, and pollution), demonstrates that none of these two sets of criteria is enough for assessing sustainability of school buildings. BREEAM does not include the social aspects of sustainability such as inclusion, participation and fair shares for all. Nor does it take account of what makes a good learning environment (for example, daylight, integration of external and internal space, flexibility of spaces for different uses, adaptability of building structure etc) [6]. The Children s plan, on the other hand, does not make broader issues, such as management and ecology a part of its main agenda. M.Malekzadeh@lboro.ac.uk 1

2 SET211, 1 th International Conference on Sustainable Energy Technologies, İstanbul, TÜRKİYE, 4-7 Sep. 211 National College for School Leadership [6] offers a composite list of sustainability principles based on BREEAM schools and the National Framework doorways as well as sustainable learning elements from past work by the Teaching and Learning in 22 Review Group [9] and Cambridge Architectural Research. This list includes 15 main areas for determining the level of sustainability in a school. These areas are management, energy use and CO2, renewable energy, ventilation, lighting and daylight, transport, water, materials, waste and recycling, land use and ecology, pollution, personalising learning, promoting pupils learning and engagement, inclusion and participation, and fair shares and employment. 2. Principles for a sustainable school building Above approaches provide a broad platform for sustainability studies within schools. However, some of the points emphasised by them are not in the scope of the present study. Therefore, a new list of 1 criteria is introduced by applying necessary adjustments to NCSL s list to suit this study. On this basis, a school building receives sustainability points for: Cooperation and participation: where there is evidence that all relevant stakeholders participate in major decisions about school environment; Energy use and CO2: where energy use for heating, lighting and appliances and CO2 emission are significantly lower than the target levels stipulated in the building regulations; Lighting and daylight: where there is evidence of adequate daylight in all areas, with glare control and energyefficient lights and controls; Management: where the school has a formal management approach that seeks to minimise environmental impact, including training for staff and the setting and monitoring of targets for energy, water and waste; Pollution and waste: where there is evidence that both construction and utilisation of the building generated the minimum of waste and recycled or reused as much as possible of the unavoidable waste; Renewable energy: where a significant proportion of energy used on site (five per cent plus) is generated from renewable sources; Responding to local environment: where there is evidence that the building s impact on habitats and biodiversity has been minimised; Travel and traffic: where private car travel is discouraged and there is exemplary provision for pupils to travel to school on foot, by bike or on public transport; Ventilation: where there is evidence of sufficient ventilation for all teaching areas for pupils to concentrate, at the same time as reducing energy use for ventilation; and Water: where there is evidence of low-consumption water services and/or large-scale rainwater harvesting with sustainable urban drainage systems (SUDS). This paper discusses application and management of technologies that facilitate each of the above elements and, thus, increase the sustainability level of the school building in two case studies. 3. Case studies 3.1. Case study A The environmental philosophy of this school s design was to create an integrated internal and external environment that would encourage its students thought and investigation by providing a joyful and inspiring environment. The challenges faced by the school leaders included integrating two schools with different needs, while emphasising on the sustainability ethos despite budgetary constraints. Background - School type: secondary (a combination of two separate schools, one for students with special needs) - School size: 949 students and teaching staff - Site type: on a hill top with views to conservation area. - Total value: 33 million 2

3 SET211, 1 th International Conference on Sustainable Energy Technologies, İstanbul, TÜRKİYE, 4-7 Sep Design start date: 24 - Completion date: spring 29 Aims Sustainability has been part of the agenda for school management from the start of the project. During the briefing stage, the aims for the new design of the school included: to create an integrated internal and external environment that would encourage its students thought and investigation by providing a joyful and inspiring environment The boundaries between the building and the external space would be blurred; and to relate to the rich local history, culture and nature Sustainability outcomes The project has done well to reach those aims, although some of the original ideas have not been implemented and/or utilised. This section discusses some of these achievements and shortfalls and relates them directly to the ten sustainability principles, mentioned before. Cooperation and participation The students and staff were involved in the process of design. Sufficient training was given to the staff and students at the beginning of take-over. This is not repeated in a regular basis. Communication between facility management (FM) and staff has been acceptable, but improvement is necessary. Staff and students were not clear on the amount of energy usage and carbon emission and ways to lower them. Energy use and CO2 Central heating is provided by low-energy, high-efficiency condensing gas boilers. Strict routine maintenance and monitoring of the plant room are observed. There is no heating control in the classrooms. The heating is mainly controlled by the BMS (both locally and remotely). The user satisfaction with this scheme is as low as 45% among pupils and 28% among teachers. The general viewpoint of the users favours a system allowing them more access to the controls. The energy consumption and whole-life costs of the investments are currently being monitored. The structure of the main building is high-density materials (reinforced concrete and heavy concrete block work). This helps retaining heat and, thus, keeping the building warm in winter and cool in summer. This, however, means a need for a longer warm up period in winter mornings, which has been a matter of dispute between school management and FM. Too early operation of the systems means extra cost for the FM and shortening this period could cause lower temperature in the first hour of the arrival of the staff. Lighting and daylight Light wells in corridors and between classrooms have proved to be very effective in allowing daylight into the school, as well as allowing views out of all the classrooms to the sky. Arts department has been designed to make the best use of the daylight by full-height windows facing South. Light fittings in the corridors have light-sensitive dimming controls to reduce unnecessary energy use. This alone was seen by the designers to help reducing electricity use of the building by up to 5%. This level is achieved and, occasionally, exceeded during summer, but in the periods of lower natural light level (i.e. winter) the dimming rarely happens and, therefore, the projected reduction in electricity use is not met (Figure 1). Pollution and waste All paper is collected for recycling. There seems to be enough paper recycling bins in and around the school. Occasional abuse of this facility has been reported. Part of kitchen waste is composted for use in the gardens. Responding to local environment - Preservation of the historical views The views towards nearby historical area have become central symbols for sustainability and continuity. These views have determined the geometry of the building, which is a south-facing crescent that contains most of the classrooms on two storeys. 3

4 Jan Feb Mar Apr May Jun Jul Aug Seo Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Seo Oct Nov Dec SET211, 1 th International Conference on Sustainable Energy Technologies, İstanbul, TÜRKİYE, 4-7 Sep Green roof Parts of ground floor roof had been designed to be covered in greenery, overlooking the central break-time area. This idea was abandoned later in the design process and bare roofs are now visible from both inside and (from higher angles) outside the school Figure 1 Average energy saved per day by light-sensitive dimming in case study A during 21 (%) Figure 2 Average electricity generated per day by photovoltaic panels in case study A during 21 (%) Renewable energy The roof is designed to include 9m2 of photovoltaic panels to generate 1 per cent of the school s power, with the potential to sell any surplus to the national grid. The pupils were planned to be able to watch the panels performance on a screen in the main corridor. Neither the grid trade nor the pupil monitoring has been materialised until now, which means that the surplus electricity generated in summer time is mainly wasted. Ventilation All areas of the building are naturally ventilated: - The upper classrooms through Automatically opened windows close to the ceilings - The lower classrooms through large windows with manual control - The central corridor and ancillary spaces by dragging fresh air through windows in the break-out areas and venting through openings in the ceiling. Disabled students school has potential for mechanical ventilation in all areas. Teachers have the right to select to use either natural or mechanical ventilation based on the conditions of their pupils. Water All toilets have been equipped with low-flush facilities Case study B The building includes a number of environmental technologies and approaches and has benefitted from strong project management and cooperation of all stakeholders to make the best use of them. The fact that the new school was created while preserving its initial sustainability vision despite lack of financial resources and sustainability knowledge is now being used as a model for other similar projects in the UK. Background - School type: secondary - School size: 14 students and 15 staff - Work type: new build - Site type: old school grounds - Total value: 36 million - Design start date: 25 - Construction start date: May 28 - Completion date: September 29 4

5 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec SET211, 1 th International Conference on Sustainable Energy Technologies, İstanbul, TÜRKİYE, 4-7 Sep. 211 Aims The demand for a new building was identified and acted on through a partnership between the local community, the funding consortium and central government. The project vision was for a school that would fully integrate with the local community and environment. The resulting building has proved to be a model school that continues to inspire students, staff and the local community alike. Sustainability outcomes This section highlights some of the achievements and shortfalls and relates them directly to some of the ten sustainability principles introduced earlier in this paper. Cooperation and participation School has involved staff, pupils and the wider community fully in this project during the design process. The importance of communication between stakeholders is understood. Therefore, students curriculum includes education on the importance of sustainable development. School council includes a specialist eco-committee that devises plans for energy, CO2 and waste. Lighting and daylight Energy requirements for lighting have been reduced by incorporating a south-facing atrium that invites natural light to the building. Classrooms have also been designed to have large windows. The amount of light allowed in the classroom is controlled by Louvres. Pollution and waste Paper and plastic are collected separately for recycling. Almost all students understand the importance of recycling and observe it. Kitchen waste is disposed at the moment. Negotiations are going on between school management and the FM for the purchase of a composter. Renewable energy Photovoltaic panels on one roof are designed to provide five per cent of the school s electricity needs in winter and 1 per cent in summer. The average amount of actual electricity generated in this way is very close to these predictions, especially in the summer (Figure 3). Students can monitor the performance of the panels through a screen in the main entrance hall Jan Mar May Jul Sep Nov Figure 3 Average percentage of electricity generated by photovoltaic panels in case study B during 21 (%) Figure 4 Average percentage of the water heated by solar energy during 21(%) Mains water is heated by solar energy before reaching the boilers. This reduces gas heating load of the building considerably, especially in summer (Figure 4). Travel and traffic Students are encouraged to use more sustainable transport methods (walking, cycling, public transport, school service, car share plan, etc.) Water Rainwater from the roof feeds the toilets via a tank within the building. The system has been efficiently explained to all students and main entrance screen reports the amount of water collected and used in each week. Depending on weather conditions, this system can provide up to 5% of the water used for flushing toilets (Figure 5). 5

6 SET211, 1 th International Conference on Sustainable Energy Technologies, İstanbul, TÜRKİYE, 4-7 Sep Jan Mar May Jul Sep Nov Figure 5 Average percentage of the rain collection in toilet flush water during 21 (%) 4. Conclusion Case studies discussed in this report are good evidence to the fact that a sustainable design is necessary for having a sustainable environment, but it is never enough. Wherever maintenance, monitoring, training and most importantly, understanding and appreciation of the systems follow a good design, the level of excellence envisaged by the designers is achieved and even exceeded. Absence of any of these links will lead to the partial or total failure of the systems and significant waste of the funds spent for such projects. Constant collaboration and communication of the designers with users and managers of the building may be one determining factor in preventing such failure. The transfer of knowledge and enthusiasm from those participated in the design process to those who use and maintain the products of the design needs to be observed throughout the lifetime of the building if the aims of the building are to be met. References [1] Malekzadeh M, Bouchlaghem D, and Wheeler A, Predicted vs in-use performance of buildings, 9th International Conference on Sustainable Energy Technologies, Aug 21, Shanghai. [2] Andreu I, and Oreszczyn T, Architects need environmental feedback Building Research and information. 32 (4), (24). [3] De Wit S, Augenbroe G. Uncertainty Analysis of Building Design Evaluations 7th International IBPSA Conference on Building Simulation Aug 21, Rio de Janeiro. [4] Office of the Deputy Prime Minister, Approved Document L2A: Conservation of fuel and power (New buildings other than dwellings), HMSO, London (26). [5] Davis J, and Ghani A, Private Finance Initiative (PFI) school procurement, DTI, London (26). [6] Wilkinson J, Leading sustainable school building projects, National College for School Leadership, London (29). [7] Department for Children, Schools and Families, The Children s Plan, HMSO, London (27). [8] Building Research Establishment, Building Research Establishment Environmental Assessment Method (BREEAM), BRE, Watford (26). [9] Teaching and Learning Review Group, Report of the Teaching and Learning in 22 Review Group, DfES Publications, Nottingham (26). 6