The perfect balance is within reach
Lighting accounts for 17.5% of global electricity use, and it is an area where great savings can be made but it is important that when making these savings we take into account the needs of the building users. David Trueblood, Managing Director of Riegens Lighting, explains more.
Artificial light is something that we all take for granted but perhaps because of this it is one of the greatest causes of energy waste in commercial buildings.
Far too often lights are left on when the building is unoccupied or when there is sufficient natural light and therefore we need to integrate increasingly efficient lighting systems and methods of using them. The key however is to ensure that these efficient solutions continue to provide an attractive working environment.
We have all seen the figures which suggest that employees work better in a well-lit and attractive environment but what we need to do is find the right balance between attractive and efficient in order to satisfy the demands of the bill payer and the occupants.
If you’re like most businesses then the chances are that you can comfortably reduce your lighting costs by up to 70% and still improve the quality of light for the occupants of the building – and it could be more cost effective than you might think.
The simple fact is that by replacing older light fittings with modern alternatives you can make instant savings and by taking the savings into account the payback period can be vastly reduced. A good example of this would be a typical luminaire which absorbs more than 50% of the light emitted by the light source. The more efficient alternatives absorb less than 10% giving you a better quality of light at a fraction of the cost.
But even the best energy efficient solution will have its drawbacks if it isn’t planned correctly and therefore you need to find the perfect marriage between design and function.
Is it too bright?
Lighting within a building must provide a suitable illuminance level for the tasks being completed and it must also meet all of the needs and demands of that particular installation. Therefore depending on the use of the space, the lighting will need to comply with the relevant standard or guide and for this there are numerous considerations which need to be taken into account.
In a commercial building for example where people spend a lot of their time working at a computer there must be a degree of illuminance control to reduce glare and reflected glare on computer screens. By using a luminaire with a dedicated optical system you can provide the optimum comfortable working environment which also fulfils the requirements set out in the European Standards and Lighting Guides.
Luminance levels in commercial buildings however have been the topic of many discussions and research has shown that the developments in screen technology have led to screens becoming more tolerant to brightness. There have therefore been suggestions that the values stated in the Lighting Guides do not recognise this and that in fact screens are able to endure a much higher luminance value without vision being impaired.
Another factor which must be taken into consideration is the luminance distribution within a room. It is a well known fact that people work better in a bright, well lit environment and therefore using a luminaire with optimum glare control and light distribution will lead to enhanced performance in the workplace. But again you need to find the perfect balance because if the environment is too bright it can also give the impression of glare which can be very counter-productive.
One of the final things to make comment on is the use of control because this is one area where great savings can be made. To put it simply if it isn’t switched on then it isn’t costing you anything and therefore the inclusion of lighting control is an opportunity to combine better lighting comfort while reducing operational costs.
There is a vast range of lighting control systems on the market which offer the flexibility to control anything from a single room to a large commercial building. The addition of daylight linking further adds to the savings which can be made by making use of natural daylight and allowing luminaires to be dimmed accordingly. The addition of presence/absence detectors will also ensure that lights are switched off when they are not in use.
Finding the right balance can be difficult, particularly when you want the end result to be energy efficient, blend in with the aesthetics of the building and provide the perfect levels of luminance for the occupants of the building and the tasks they are carrying out. But it is certainly not an impossible task and if it is designed properly your lighting scheme can combine form and light to create a modern and stylish solution for any building.