Building-management systems as the key to energy-efficient buildings and reducing greenhouse gases
Energy savings of anywhere between 25 to 50% can be achieved using the building-management system to accurately set occupation times, changing temperatures to reflect actual use.
The key to the Government’s target of reducing carbon-dioxide emissions by 20% is already in place in many buildings. The key is to use building-mangement systems effectively, argues Alan Aldridge.Modern buildings include in their design, almost by default, a variety of management systems aimed at producing a building that operates efficiently — and that means at the lowest operating cost. Included in ‘management systems’ are: building management and control; metering; monitoring and targeting; CCTV and security; fire alarms, and more. In most cases, these systems find themselves in a tug-of-war. At one end of the rope are organisations seeking to evaluate whole-life costs in order to determine their role and scope. At the other end of the rope are contractors concentrating on installing each system at the lowest cost to them within the shortest time. The considerations of the client who requires a productive working environment that is easily managed are so often conveniently ignored — even though they probably instigated the project. ESTA maintains that, in many cases, the very structure of construction contracts works against the interest of the client. It would therefore be reasonable to go back to basics and see why these systems are used, their role and the benefits that they bring to users. Safe and productive
The primary role of building services and their management systems is to provide a safe, productive working environment. When regarding the building as an asset, building services and management systems are there to protect the building from damage (as caused by frost, for example) and to provide some degree of support to ensure that the building fabric does not deteriorate through mould and damp. The safety of personnel and visitors is a legal requirement which impacts on fire alarm, evacuation and ventilation systems. CCTV and other security systems have the ability to keep a business operational through the early identification and management of acts of terrorism, vandalism and sabotage. The workspace is serviced by the HVAC and electrical systems, and monitoring their individual performance and their interaction with other systems will minimise the risk of failure or deterioration in performance. Finally, providing a comfortable environment for staff, visitors and customers is paramount. Surveys have shown that, often, up to 85% of running costs are related to staff. In retail, hospitality and leisure outlets it is a well known fact that poorly serviced customers rarely return. Reducing emissions
The Government programme for reducing greenhouse-gas emissions is on course to meet the Kyoto targets of 12.5%, but the internal target of a 20% reduction in carbon-dioxide emissions is at risk. The current measures that impact on building and process operations and for which management systems are an essential tool are climate-change agreements (soon to be extended), Emissions trading (soon to be the EU scheme), ‘Energy performance of building directive’ (to result in substantial updates in Building Regulations and including building energy certification or labelling), and an EU energy services directive. However, even with these measures, it appears that to achieve the Government’s target of reducing carbon-dioxide emissions by 20% additional measures will be required, and it is very likely that business and the non-housing public sector will be asked to make major cuts. When responding to legislation, it should be remembered that no matter how efficient the building technology is (e.g. natural ventilation, heat pumps, variable-speed drives etc.), building performance will be severely compromised if due attention is not paid to providing well trained and resourced active management. ESTA has many examples of buildings that, given sustained management attention for just a few months, have achieved anywhere between 25 to 55% energy savings. In most, cases the solutions have been simplistically easy: setting accurate occupation times, ensuring plant is not left permanently running, changing temperatures to reflect actual use, ensuring lighting is controlled in small zones etc. Event monitoring allows every change to be noted and checked against current demand, enabling efficiency adjustments to be made, plant failures to be rectified (and, with the right data, even anticipated) and the early analysis of future best practices. On most, sites investment in setting and maintaining the building-management systems is by far the best-low cost measure that owners can take. With this in mind, ESTA contends that management systems need to be viewed as having the same priority as the physical plant and building services. Further, training in the operation of the site’s management systems and its basic plant should be another primary objective. ESTA runs courses that cover the essential and advanced requirements in building services control and these are open to all. To summarise, ESTA believes that attention to management systems is justified based on energy and operational savings and on workplace productivity in both existing and new buildings. The contractual chain needs to pay more attention to delivering the acknowledged needs of the client, who, in turn, should embrace the training required in ensuring that a good management system is supervised by informed staff. Alan Aldridge is executive director of the Energy Systems Trade Association, PO Box 77, Benfleet SS7 5EX