Getting lighting costs under control
Peter Haseler argues that a more strategic approach to controlling lighting requirements can deliver real benefits in terms of energy cost reductions and operational effectiveness.
As businesses continue to seek ways to reduce costs and improve efficiency they will often look at obvious areas of operation such as personnel, processes or purchasing. However, a key area is often overlooked which could have significant impact for all types of companies, organisations or bodies charged with controlling interior or exterior space. That area is the control and use of lighting.
With soaring energy bills over recent years and predictions that high energy costs are set to stay, taking a more strategic approach to lighting and its control to support requirements of public safety, security and comfort, as well as ultimate energy costs, could result in real cost-saving benefits and help reduce CO2 emissions.
Such a strategy should include and utilise the advantages of lighting-control technology to deliver appropriate lighting for any given situation in the most energy-efficient manner possible. By adopting such an approach, short-term and ongoing cost savings are entirely feasible. Indeed, organisations across the UK are already reaping the rewards of implementing lighting control requirements without compromising comfort, safety or security.
|Daylight is free and should be used to reduce a building’s lighting bill.
At a fundamental level, those in charge of a building should ask themselves if they are making the best of harvesting and controlling access to what is a ‘free’ commodity — daylight. Every time a light is turned on in a building it generates a cost. Applying automated lighting control technology to a building and adopting an intelligence-led approach makes it possible to maximise use of both natural light (no cost) and artificial light (business cost) to achieve optimum lighting.
Making a building think for itself in conjunction with its natural environment is key. Digital Addressable Lighting Interface (DALI) is the most flexible way of controlling lighting running gear to deliver the precise amount of light constantly to keep people in a building safe and comfortable at all times through the day. And there are also bottom-line benefits.
It is generally accepted that in a typical building about 28% of electrical consumption is due to lighting. For a typical annual energy bill of £1 million, lighting therefore accounts for some £280 000. Real inroads can be made into such a substantial business cost. Installing a digital ballast control gear system (such as Siemens’ Gamma, which complies with the KNX protocol for building controls ) will, for example, only illuminate areas when occupied. Intelligent building-management systems enable less focus on a single issue and more focus on the total picture by getting ‘islands of intelligence’ communicating and working with one another. Such holistic controls can reduce energy consumption by up to 44%— or about £120,000 a year for this example. With capital payback period on such a system being about two years, investment in such systems will generate both short-term and long-term cost benefit.
|Do they actually need to be on? Presence detection can turn off lights when they are not needed and indicate to the building-management system that other services can be set back.
As well as the cost saving, comfort and security issues addressed through a strategic approach to lighting control can also accrue other spin-off benefits. A system such as the Siemens’ Gamma KNX can contribute to an overall ‘Excellent’ BREEAM rating.
Such Government-backed requirements for buildings to be more energy efficient demand that from a building-control perspective, integrated systems must be able to detect and communicate status with others. This is a pre-requisite for the ‘Excellent’ standard. Such a status is achieved by control devices talking to relevant control devices within a single communications platform. This means that the Gamma system, for example, senses event or demand changes in parts of the building where energy reduction is required and talks to the building-management system to help achieve this.
Businesses or public organisations should be examining ways of managing energy use more strategically. The daily requirements for lighting can play a central role in any such thinking. By using open-based lighting control systems, large-scale multi-point applications or low-level presence detection devices can form an integral part of any energy-management focus. Lighting-control systems can help fulfil all or any one of user and occupant security, safety or comfort objectives for building operators — and, importantly, help to do so in the most energy efficient manner possible.
It really is a win-win situation.
Peter Haseler is with Siemens Building Technologies.