The growing pressure to boost energy efficiency
Published: 03 June, 2015
Mitsubishi Electric’s Scott McGavin looks at what legislative changes mean for building operators and manufacturers, and how improvements in design and controls are helping increase seasonal efficiencies and performance.
Our built environment is responsible for 40% of carbon emissions, so there is a determined drive to improve the efficiency of energy-consuming equipment in our buildings. There have already been several changes in legislation which increase the pressure on both equipment manufacturers and building operators, and this trend is set to continue as we look for ways to tackle climate change.
There are several legislative drivers focusing attention on energy performance. Parts L and F of the Building Regulations and the Energy Performance of Buildings Directive have all had their part to play — and have now been joined by the Government’s new Energy Savings Opportunities Scheme (ESOS).
Every company which qualifies for the scheme must monitor and report energy usage once in every four year period, beginning in December 2015. They will come under increasing pressure to act on recommendations which are made to help improve their score.
Although the requirements of the scheme may seem onerous, there is a distinct upside in terms of the financial savings that can be achieved.
Whilst the Department for Energy & Climate Change (DECC) predicted that ESOS will result in an average investment ‘per enterprise’ of £15 000, it is also predicted that as a result, average potential energy-bill savings will be £56 400 per year.
ESOS applies to large, non- public sector organisations with more than 250 employees.
However, we are moving to the day when all buildings operators face similar pressures to demonstrate energy efficiency, with energy labelling likely to become the norm.
Although the figures from DECC on return on investment are quite a compelling, it may not be quite so straightforward because the Carbon Trust also estimates that whilst most spending on energy efficiency has a return on investment of 50%, actual experience shows that 60% of energy savings opportunities are simply not implemented.
So what about the manufacturers and the equipment on offer?
There is already a move to energy labelling of equipment that will allow building operators to judge building-services efficiency in the same way they can a washing machine or a fridge.
The Ecodesign Directive establishes a European framework to set mandatory ecological requirements for energy-using and energy-related products sold in all member states.
Under Lot 10 of the Directive on Energy-related Products (ErP) this labelling already applies to all air conditioning under 12 kW, with affected units needing a data sheet detailing seasonal coefficient of performance (SCOP) and seasonal energy efficiency ratio (SEER) data in three specific climate zones, as well as the more traditional COP and EER.
At Mitsubishi Electric, we have long championed the use of seasonal efficiency as the best way of delivering a truer picture of performance. This is because it provides clearer visibility of product performance, energy use, running costs and emissions.
Although the expansion to cover larger systems has been delayed, there are already many VRF products available which have been designed to meet this requirement now — over two years in advance of future legislative changes.
The importance of control
What is needed is a more holistic approach to building services, and this will be easier to achieve through the increased use of advanced controls, all integrated into a single building energy management system (BEMS).
A key factor driving this is legislation in controls as a means to save energy was bolstered by the recognition in the new Part L 2013 Compliance Guide of British and European Standard, BS EN15232: 2012 ‘Energy performance of buildings — Impact of building automation, controls and building management’.
At the heart of the BS EN15232 is a very straightforward and well-known approach to building services which is demand-driven. This ensures that services such as lighting, heating and air conditioning are only used when required.
Problems stem from the fact that all of the plant and services come with their own control system which invariably works in isolation. This is ideal when the equipment must work in isolation, but what we also need is an intelligent approach that allows the controls of individual plant and services to be used as more than a simple on/off switch and communicate with other equipment, when required, to achieve the best results.
This was one of the driving forces behind the introduction of MelcoBEMS which provides an interface between Mitsubishi Electric air conditioning equipment and a BEMS via the Modbus or BACnet protocol. MelcoBEMS is fully compatible with a wide range of systems from BEMS manufacturers such as Siemens, Priva Building Intelligence, Delta Controls and Satchwell.
This ability to work seamlessly with technology from other manufacturers is central to facilitating the demand-driven approach that must be adopted if optimal operating efficiency is to be reached.
What this means for a commercial building is that to get the best from your high-specification kit and intelligent BEMS, the two must be fully integrated.
Mitsubishi Electric has produced a series of free CPD Guides on legislation including ESOS and the Ecodesign Directive, which are available to download from the dedicated online library: link below.