The drawback on a single metric for measuring the payback, i.e. the financial return of investment based on energy savings, is it does not capture the other benefits that can be accrued.

Our experience in assisting clients in the full life cycle of an LED lighting upgrade has provided an insight to tangible yet hidden benefits:

Financial benefits

Commercially mature and reliable LED lighting projects should now be providing a 50% to 65% annual rate of return.  

The rate of return uses the capital costs less the energy and maintenance savings. The main variable is in the amount of hours per week the system is being used (168h/week for a 24/7 operation to as little as 60 for a single shift Monday to Friday operation).

Another cost saving is in the reduction of spare stock required due to the increased life-span of LED systems. This not only includes quantity but also variation in types of fittings. One industrial customer has reduced 15 variants of light fittings/fixtures to four, eliminating an estimated £4000 of redundant spare parts.

Occupational benefits

There are many standards based on countless hours of research as to the optimum level, colour rendition and colour temperature of light depending on functional requirements.

LED lighting's ability to standardise both colour rendition and colour temperature comes into its own in industrial environments where we see up to four different colour rendition indexes (CRI) in a single area. Each ‘lighting function’ may be very different: high bays at 30CRI, mezzanine lighting at 60CRI, task lighting at 80CRI and inspection lighting at 90CRI. A typical industrial client can reduce this to 80CRI for all but inspection lighting.

This provides a uniform level that people do not have to visually adjust to as they move around the area. We have noted a number of anecdotal conversations where staff say that they do not feel as tired after a shift with the new LED lighting in place. 

Further benefits include the elimination of UV radiation and light flicker. The latter is particularly beneficial for those who have high photosensitivity.

Environmental benefits

The environmental benefit of greenhouse gas reduction is well documented with up to 70% reduction in typical LED projects.

However, what is not as readily documented is the elimination of mercury from buildings.  Most lighting systems, especially fluorescent lamps, contain mercury vapour. This can be up to 5mg per average 1200mm T8 tube. Upgrading a typical facility may result in eliminating 50g of mercury from the site.

As part of many projects we deliver, the client needs to quantify the resulting waste stream of the installation (packaging, obsolescent fittings/ ballasts and old lamps) as well as forecasting the future waste stream due to ongoing maintenance. The ongoing waste stream is typically reduced by at least 50% and in some cases as much as 80%.

Quality benefits

One benefit that may not be directly attributed to LED technology is the increase in quality. This is pervasive in the industrial sector as the lighting levels and the lighting quality is siginificantly increased.

One example we have captured is the reduction of 18% in downstream defects in a manufacturing process. This was directly attributable to an LED Lighting project in which the lighting levels remained the same but the colour rendition increased and the colour temperature moved up from natural to daylight.

A second example is the perceived increase in productivity due to the reduction in flicker and standarisation in colour rendition and colour temperature across a facility.

For many organisations LED light is still viewed with trepidation due to its perceived infancy. The reality is that most major lighting manufacturers have quality products.

It is up to internal decision making processes within an organisation as to when they invest in LED lighting. This requires a robust business case that includes not only the financial benefits but the other benefits that come with a step-change technology.

Our advice to clients that need to formalise this process is to begin with a trial that captures results of each benefit: financial, occupational, environmental and, if possible, the quality improvements.