Building Energy Management Systems can achieve the cost and carbon saving benefits businesses are seeking.
One of the most efficient methods of reducing energy consumption is a Building Energy Management System (BEMS), yet many organisations overlook BEMS in their energy efficiency plans because of the false belief that they are an expensive technology for big business that are complex and costly to specify, install, operate and maintain.
Such thinking sets back energy efficiency progress, particularly among SMEs. BEMS can provide the quick wins on cost and carbon reduction organisations are seeking. The best systems will typically reduce consumption by 25% to deliver rapid payback on investment and reduce taxes on carbon emissions.
In developing its next generation E-MAGINE(www.emagine-controls.com) BEMS system, ENER-G, designed a new type of modular HVAC controls system that was more accessible and affordable for smaller businesses, while also meeting the complex requirements of large multiple site organisations.
E-MAGINE has the dual benefit of acting as an automatic monitoring and targeting system, monitoring, measuring and analysing consumption to assist with carbon reporting and managing efficiency. This enables users to meet increasing environmental legislation, such as the CRC Energy Efficiency Scheme.
The increased drive to energy efficiency has prompted innovative 'pay as you save' financial models to increase access to new technologies. ENER-G’s guaranteed savings contractsare one example of private sector shared savings agreements. Under such schemes, upfront capital is covered so that customers can install technologies that will reduce their energy costs and then use the savings made to pay for them. This gives organisations the ability to make improvements even when budgets are tight and no capital is available: the anticipated energy and operational cost savings offset the cost of the upgrades.
Another reason why BEMS get overlooked is that specifiers have had poor experiences of traditional systems, falling victim to three classic system flaws. Historically, these have prevented many traditional building energy management systems from delivering their projected cost and carbon savings over their lifetime.
The first classic flaw is inconsistent programming. It is often the case thatno two controls specialists will program a BEMS in exactly the way specified, or indeed to a similar standard - adding to the problems associated with on-going support. This causes significant deviations in the way the hardware operates, which in turn can increase energy consumption. Although there are recommended control strategies from CIBSE and BSRIA, these are not always adhered to. On complex installations where there are a multitude of energy sources requiring the passing of demands between them, the quality of the programming has to be absolutely first class to ensure that optimal control strategies are achieved.
Such inconsistency can be exacerbated during the final system refinement stages. Due to time or cost constraints, this is often left to the on-site commissioning engineer who is always under pressure to get the BEMS working quickly to meet the building handover programme. Invariably, with little time left in the schedule, BEMS control strategies may not be carefully verified or thoroughly exercised pre or post-handover, and so the BEMS can start life operating with less than optimal functionality.
In developing its E-MAGINE building control system, ENER-G took the decision to design out human shortcomings. As such, the programming for a bespoke project can be pre-configured to embed optimised energy performance,removing the dependency on an individual engineer’s programming skills. It also makes the system’s design and installation much simpler and faster, while commissioning can be completed remotely – reducing time on site and cost.
The second traditional flaw of BEMS is ‘twitchy finger’ syndrome, where various users adjust the settings and gradually erode the energy efficiency benefits. Tampering is widespread - caused by poor building design or comfort preferences, or simply the different temperature preferences between occupants or genders. At the user level, temperature and time set points are fiddled with continuously in the search for optimum conditions. At the plant level, to overcome system deficiencies, changes are made to keep the system operational -often at the cost of extra energy use. The net result is that the intelligent self-adaptive optimisation strategies of a BEMS cannot achieve its goals.
E-MAGINE use tamper proof controls to minimise the impact of any changes made - by restoring optimal settings. This ensures that the system achieves peak optimised savings and performance throughout its lifetime, while delivering maximum levels of comfort and flexibility throughout the property.
The third, and often hidden, problem of traditional BEMS systems can be the inevitable issue of hardware and software deterioration. Critical parts of anyBEMShardware and software will require servicing or maintenance over the system lifetime. For example, temperature sensors can deteriorate and fall outside their calibration accuracy or simply become broken or damaged; control dampers and valves can fail to function correctly due to age or wear. The other most common problems occur with temperature dead bands and free cooling options. In addition, control software can become out of date. Ultimately, failure to address problems means that the BEMS system no longer serves the intended purpose and is relegated to serving as a glorified time clock to start/stop the energy systems - thus failing to deliver the original intention of energy, CO2 and cost savings.
E-MAGINE makes use of online diagnostic tools, whereby system performance can be continuously monitored. This will quickly identify system malfunctions and automatically refine control strategies to restore optimum operation.
Further information: www.energ.co.uk/controls 01527 855072