The Business Case Annual fuel cost savings of 26% worth more than 28,000 Annual fuel savings of 1.3million kwh Annual CO2 savings of over 245 tonnes

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1 North Lanarkshire Council The Business Case Annual fuel cost savings of 26% worth more than 28,000 The Sir Matt Busby Sports Complex is an important local facility for the people of Bellshill, North Lanarkshire. The sports and leisure complex, a North Lanarkshire Council property, offers a combination of indoor and outdoor sporting facilities including a floodlit synthetic football pitch and a comprehensive mix of swimming, sauna, gym and sports hall facilities. The complex achieved QUEST 1 quality accreditation in early Having worked hard to achieve this quality standard, the Facilities Manager is committed to maintaining and improving quality. Energy efficiency offers an opportunity to derive both cost and quality benefits. Annual fuel savings of 1.3million kwh Annual CO 2 savings of over 245 tonnes Many buildings require heating, ventilation and airconditioning (HVAC). Ensuring that the correct levels of heating and air conditioning are provided, at times to suit the use and occupancy, is an important means of controlling energy consumption, cost and of maintaining the most comfortable environment for the occupants. The Sir Matt Busby Sports Complex has a wide range of HVAC demands and associated plant. The installation of a comprehensive, automatic control by Buildings Energy Management System (BEMS) has reduced fuel consumption by more than 25%. 1 The UK national standard for excellence in sports and leisure management. North Lanarkshire Council social and environmental responsibility North Lanarkshire Council is responsible for the management of over 900 properties, with an associated energy spend of over 6.4million. The Council is committed at both corporate and personal levels to reducing its environmental impact, through its Social and Environmental Responsibility policy. This recognises the environmental and cost benefits to be derived from energy management. The Council has embarked on a comprehensive programme of energy efficiency improvements across all managed properties and purchases green energy. The Housing and Property Services department of North Lanarkshire Council provides energy efficiency advice and technical services to all Council departments and supports the Corporate Energy Group through its dedicated Energy Unit. The local management team, supported by the Council s energy advisors, have considered every aspect of energy efficiency and environmental improvement. Improving the building services control with the installation of a BEMS is just one of several projects that have been implemented. For example, new efficient lighting and controls have reduced power consumption by more than10% refer to Good Practice Case Study CTS001. The Sir Matt Busby Sports Complex is one of many facilities being refurbished to improve quality and reduce costs. The Carbon Trust is assisting the Council by identifying and prioritising energy saving opportunities and providing a prioritised implementation plan for many of the Council properties. This partnership arrangement and the Council s access to 930,000 of public sector spend to save funding, provided by the Scottish Executive, is allowing similar projects to be implemented across North Lanarkshire. The business benefits These improvements have: reduced energy consumption and cost increased comfort through automatic heating and cooling controls Reduced staff intervention with automated and preprogrammed heating and cooling strategies.

2 Building Energy Management System (BEMS) A Building Energy Management System (BEMS) is simply a programmable control system used to provide automatic control of building services and other energy consuming plant. A BEMS differs from conventional control systems in a number of important ways, allowing: integrated control of heating, ventilation, cooling and lighting systems networked control of complex heating and cooling strategies intelligent, demand driven and learned control responses simple easy to use controls interface data interface and the integration with monitoring and targeting systems. A stand alone controller will typically have the capacity to control several plant systems, and can link or cross-reference the control of several plant items such as heating, ventilation and airconditioning (HVAC). In larger buildings several controllers may typically be used to provide control of HVAC plant, e.g. for different floors or departments, or for areas with differing functional and setpoint requirements. Multiple controllers can be inter-linked via dedicated cable, intranet, modem or ISDN. The use of a BEMS allows a degree of control optimisation that would simply be impossible with manual or even basic automated control systems, offering intelligent demand or loop led correction or trimming to optimum start-stop and weather compensated control functions. Although the BEMS controllers may actually be performing quite complex, and in some cases intelligent functions, the user interface can be extremely simple with little more than times and setpoints to worry about. Programme changes required to cater for special events that demand extended hours of plant operation may be made from a remote terminal where a simplified mimic diagram can improve understanding of the managed systems the contemporary equivalent of telephoning a plant operator to request the adjustment of time switches. Unlike many stand alone controllers, the networked BEMS provides both system control and data acquisition. Energy and performance data can usually be collected using the BEMS and transferred to proprietary monitoring and targeting packages allowing continuous performance management. Data collection, monitoring and targeting To perform complex control functions the BEMS collects and processes system performance data, such as: on or off inputs, from presence detectors modulated outputs from either primary transducers that measure variables (such as pressure, temperature or flow rate), or from controlling equipment (for example inverter drives) pulsed outputs from gas, electricity, or water meters. Used to the fullest potential, a BEMS can offers not only system control but also data acquisition (SCADA) functionality. Plant performance and energy consumption data, recorded by the BEMS, may be transferred to proprietary monitoring and targeting software. This will allow the generation of customised performance reports, thus providing a powerful energy and maintenance management tool.

3 North Lanarkshire Council Lighting A BEMS will accept inputs from, and provide controlled outputs for, a whole range of controllable plant, including lighting. These are useful stand-alone features but when combined with the control of other HVAC plant, significant energy savings can be made. For example, with the correct wiring arrangements a BEMS can be used to provide zone or local control including: daylight detection and automatic switching or dimming of all or individual banks of lights presence detection and automatic switching of all or individual banks of lights. Heating and cooling BEMS Control energy accurately and automatically Optimum comfort throughout a building in summer and winter, requires a flexible system with the potential to control conditions in discrete zones. If appropriate zoning exists, a BEMS can implement energy efficient heating, cooling and ventilating strategies automatically. By measuring outside temperature conditions the BEMS can estimate the pre-heat time required and adjust on a daily basis the start time to ensure that the building has reached temperature at the start of occupancy. A BEMS can control conditions within individual zones intelligently. For example, on a sunny winter s day, the rooms on the south side will require less heating than those on the colder north side. Effective co-ordination of heating and cooling can be provided for individual zones by varying setpoints. This avoids simultaneous operation of both heating and cooling systems. Maximum heating or cooling is only required for a small number of days each year. The BEMS can adjust boiler and chiller output temparatures to match actual demand on an ongoing basis. Ventilation Making the best use of natural ventilation reduces building energy costs. However, factors like humidity cannot be adequately controlled when relying on natural ventilation only, and some form of mechanical ventilation is required. Under these circumstances a BEMS may be used effectively to: control ventilation fans (and their dampers) or even automated blinds and windows, in a co-ordinated manner that will maximise the use of natural ventilation and minimise the level of mechanical support provide integrated support for active cooling systems by ensuring that the best use of natural ventilation, by for example, by pre-cooling a building at night

4 The Technical Case Building Energy Management Systems Heating, ventilation and air-conditioning (HVAC) are a significant energy cost for many buildings. This cost is often much greater than it need be, because of poor or inappropriate control. For example, this case study illustrates how savings of more than 25% were made by installing a Building Energy Management System (BEMS) to control the heating, ventilation and air-conditioning systems efficiently. In addition to the benefits of centralised and automatic control the BEMS can provide feedback and performance analyses to optimise savings. There are three principal improvements that can be made to HVAC systems: Ensure that the building is comfortable during working hours and that minimum conditions for protection of the building fabric are sustained at other times. Maintain good accurate control over heating and airconditioning setpoints Implement a combined heating and cooling strategy that optimises energy consumption. These improvements were achieved at the Sir Matt Busby sports complex by implementing the measures listed in the next column. These are all common sense measures, but it is difficult to achieve these without good control and system performance monitoring. If the operation of HVAC is largely manual or the control systems offer inadequate response, then the operator will often err on the side of caution to ensure there are no customer complaints. In practice this results in extended heating periods, over- and underheating and quite often the simultaneous operation of both heating and cooling plant clearly an undesirable situation. At the Sir Matt Busby Sports Complex, elements of the original control systems had failed over time, with the result that control of the HVAC systems was largely manual. The installation of a BEMS enabled the simple improvements tabled below illustrating the significant benefits of a good control system and strategy. In this project the council have demonstrated a weather corrected cumulative saving of over 26% or 1,294,00kWh worth 28,800. BEMS control of various systems Pool air handling In the swimming pool hall, it is important that both temperature, and relative humidity are controlled for bather comfort. The pool Air Handling Unit (AHU) is now managed automatically by the BEMS, which maximises air recirculation and heat recovery. Outside opening hours the system reverts to a night setback condition to protect the building fabric and the air handling plant is automatically shut down for long periods which significantly reduces energy consumption. Optimised start-stop control The time required to heat up the building will vary depending on heat remaining in the building and the weather. The optimised start-stop function, now provided via the BEMS, learns how the building responds to heating and fires the boilers at the correct time to ensure that the building reaches the correct temperature as the staff arrives. This optimisation function can also be used at the end of each day to shut the plant down prior to the end of occupancy, if higher internal temperatures and the weather permit. In milder weather the boilers may not be fired at all. Demand led boiler control Like many heating systems the boilers at the sports complex fire in response to the temperature of water returned to the boilers. Although there may be no actual heating demand, losses from the distribution pipework and the boilers themselves will typically cause the boilers fire regularly. This ensures that hot water is available for individual heating zones, if required, throughout the heating period. In summer there are often extended periods when there is no demand for heating and this boiler cycling simply wastes energy. The BEMS provides real time demand feedback from the individual heating zones and discontinues boiler firing unless there is actually a demand. This prevents unnecessary cycling and consequently saves energy a function that could simply not be achieved manually. Heating zone mixed flow circuits The temperature supplied for individual control zones is achieved by mixing hot water supplied from the boiler header with cooler water in the zone heating circuit. The mixed flow temperature is now governed by a BEMS programmed relationship with outside air temperature. However, the new BEMS will also offer a room trim function, sensing internal zone temperature and adapting the mixed flow setting accordingly. This capability is important for meeting and conference rooms, gyms and dance studios, where there are variations in occupancy and activity and where the heating system must respond rapidly to changes in demand. Domestic hot water Primary circulation pumps are now controlled by the BEMS. This prevents circulation when none is required and provides improved control of domestic hot water temperature.

5 The Financial Case The Sir Matt Busby Sports Complex is one of many Council properties where public sector spend to save funding is being used to implement a comprehensive range of energy management projects. Ensuring the correct and efficient operation of heating, ventilation and air-conditioning plant is a fundamental part of the Council s strategy for energy consumption reduction. Achieving QUEST accreditation is important for our business. This underlines our commitment to our customers and is recognition of the standards of service we provide. Good environmental control is a fundamentally important part of our operation and our duty management team, supported by the council s engineering staff, has driven these latest improvements. Energy efficiency has become an important part of our QUEST accreditation, not only because there are real quality improvements, but also significant associated financial benefits. Derek Park, Facilities Manager Savings The Sir Matt Busby Sports Complex refurbishment has dramatically reduced energy consumption. The cumulative savings for 2004/5 were 28,800. However, is anticipated that the council will improve this with planned modifications, including the installation of invertors to govern the operation of the pool filtration pumps. Costs The final costs for the project amounted to 17,500 giving a return on investment of less than 8 months. Expert advice The Carbon Trust provides free expert energy efficiency advice. Energy surveys Your company may qualify for a free energy efficiency survey from one of the Carbon Trust s qualified consultants. Energy efficiency loans The Carbon Trust can provide an interest free loan to SMEs in England, Wales and Northern Ireland of up to 50,000, repayable over up to five years for investment in energy efficiency measures. In Scotland the Scottish Executive offer a similar scheme called Loan Action Scotland. Publications A range of free publications is available including: Focus: Energy Saving Guide for Small Business ECG051 Energy efficiency in sports and recreation buildings a guide for owners and energy managers GPCS390 Building management system in multi-site commercial and industrial buildings For details of any of these services or free publications, contact the Environment & Energy Helpline on and select the Energy option, or visit the Carbon Trust website at For Loan Action Scotland contact howto/help/loan/. Tax incentives The whole capital value of energy efficient technologies which qualify under the Enhanced Capital Allowances scheme may be written down in the year of purchase. For further information go to Sources of further information For further information contact: The Chartered Institution of Building Services BSRIA (The Building Services Research and Information Association) Whilst we have taken reasonable steps to ensure that the information contained within this Case Study is correct, we give no warranty and make no representation as to its accuracy and we accept no liability for any errors or omissions and nor does the Carbon Trust nor the Government. Nothing in this Case Study is intended to be or should be interpreted as an endorsement of, or recommendation for any supplier, service or product. The Carbon Trust is a Company limited by guarantee, registered in England and Wales, number Queen s Printer and Controller of HSMO, February 2005

6 CTS004 Good Practice Case Study New Building Energy Management System (BEMS) reduces energy consumption for North Lanarkshire