The lights don’t need to be on
The UK is no longer a nine-till-five society. In addition to British employees having the longest hours in Europe, many businesses have embraced flexible working as a way to meet the needs of the business and help staff achieve a better work/life balance. Coupled with this, shopping hours have been extended so that some retailers are open around the clock. These activities have influenced the occupation of our buildings and subsequently increased demand for lighting.
Seen as a major energy user, lighting can account for up to 40% of a building’s total electricity consumption. As no organisation is exempt from the pressure to reduce the amount of energy their premises uses, consideration must be given to the power usage of the technologies used in its operation. This must include lighting where more energy efficient equipment such as low voltage lighting and dimming controls, can make significant differences to a company’s bottom line.
Reducing the energy consumption of the UK’s commercial buildings is not just about making sure the latest energy saving technologies are used in new developments. With the number of new builds diminishing because of the current economic climate, consultants and contractors can focus on helping businesses improve the energy performance of existing facilities. In this market, there is demand for retrofit solutions that are easy for a contractor to install.
There are three ways to affect the energy efficiency of lighting. The first is to use voltage regulation technology, which reduces the voltage supply to the lamp. The second option is to have control command components, which offer direct control of individual lights or a group of lamps. The final choice is to have an integrated system, which provides full control of the building environment at the touch of a button via automated programming.
As with the first option, devices such as Schneider Electric’s Lubio work by lowering the operating voltage to the light fitting. The component allows the operating voltage of the lighting to be adjusted so the optimum light level is provided, at the same time as achieving maximum energy efficiency. Reducing the levels of electricity also results in the longer life of consumables, such as lamps, and this can save significant amounts of money on the maintenance of commercial properties.
The second option of control command products are discreet devices that can be used as single units or as multiple solutions to create mini systems. But when it comes to using lighting devices to their optimum efficiency, it’s important that businesses consider the three core areas of a strategy – time schedule, occupancy base and light intensity. This means taking into account the time of day the space is occupied and the frequency or amount of time people spend in an area.
As part of making improvements, an organisation should also look at encouraging behavioural changes among staff and visitors, so they take responsibility for making sure lights are turned off when vacating a room. At the same time, there are solutions that also reduce the onus on employees to remember to turn off lighting when it’s not needed.
For example, occupancy is a major factor when it comes to lighting in offices, so using motion sensors which will only power lighting when the room is in use, will produce instance energy savings. Occupancy sensing will detect the presence or absence of people within the parameters of the sensor and will turn lights on and off accordingly. This solution is most suited to areas of a building where usage is unpredictable, such as meeting rooms and private offices. The use of these sensors, commonly known as presence detectors, in a private office, could save a significant amount of its yearly energy usage.
For spaces where use is much more regulated and predictable, scheduled lighting controls can be used to turn lights on and off at set periods. Time delay switches can be programmed to whatever setting is required, for as little as two minutes or as much as two hours. There is also the option to integrate a manual override device should illumination be required outside of the scheduled time.
Going beyond just switching lights on and off, a daylight harvesting control strategy reduces power to the lights or turns them off completely, depending on the level of natural light. Photosensors linked to dimmer devices will vary the lighting output and provide an ideal solution for classrooms, conference rooms and lobbies, where the space isn’t always being used and the quality of natural light varies. This will allow the user to control their own environment depending on the daylight conditions.
Where a building has several control strategies, using an integrated system is the ideal option, which provides lighting control for all areas in one location. The convenience of having these in one place can reduce maintenance and set-up costs.
In addition, the weather and subsequently amount of natural light can have an impact on the lighting level within a building and on other factors like the temperature, ventilation, air conditioning and insulation. For organisations that are committed to lowering their energy usage and being more efficient, having multiple systems to manage all these variables doesn’t really make sense. Instead using a platform that integrates lighting controls, which can be linked into the heating, ventilation and air conditioning systems and monitor power usage, can provide complete control over a building, therefore delivering greater energy efficiency.
As with all energy efficiency programmes, it’s important to constantly measure and review so that ongoing improvements can be made. Contractors and consultants are well placed being aware of the ever emerging technologies, can maintain and improve their lighting efficiency through integrated energy efficient design. Schneider Electric’s Clipsal C-Bus control system, for example, can accommodate multiple lighting controls and offers the flexibility to re-programme lighting groups to accommodate any future changes to the building, such as new office structures, partitions, or new open plan desk configurations. This type of technology is most appropriate for new builds to deliver an energy management solution, or when the building is being refurbished.
Whether an organisation uses its premises 24-hours-a-day or within standard working hours, all types of businesses can benefit from assessing the way it uses lighting and the technologies employed. As lighting accounts for a significant proportion of a business’ energy costs, utilising solutions that lower these outgoings, while improving the company’s energy efficiency, will help deliver a healthier bottom line and reduce its impact on the environment.