New lamps for old can slash energy and maintenance costs

Published:  11 August, 2009

Chalmor - Steve Henry
Informed decisions — Steven Henry.

New lighting offers many possibilities for reducing energy costs and maintenance bills — with some very short paybacks, as Steven Henry explains.

The decision to refurbish lighting inside or outside a building will usually be driven by a desire to improve the quality of the light and/or reduce energy consumption. If light quality is to be improved it makes sense to examine energy consumption at the same time.

In addition, the imminent phase-out of low-efficiency fluorescent and high-intensity-discharge (HID) light sources through Directive 2005/32/EC may mean that like-for-like replacement lamps become unavailable.

The options available will depend on the nature of the existing installation, — ranging from retrofitting higher performance lamps and control gear through to installing new fittings and, perhaps, controls. The decision should also be influenced by cost-of-ownership issues such as energy performance and maintenance requirements, as well as return on investment (ROI). Those 5000 or so organisations expected to participate fully in the Carbon Reduction Commitment programme will also need to factor in the cost of carbon allowances when calculating ROI.

It will also make sense to consider the options for funding any refurbishment work, either through grants and interest-free loans or through schemes operated by manufacturers where capital costs are funded through actual energy savings.

Taking a low- or high-bay installation using high-pressure-sodium (SON) lamps as an example, one option is to upgrade to a higher performance lamp, often necessitating new control gear as well. This may be cheapest option but may not the lowest-cost option in the longer term.

For instance, replacing 400W SON fittings with 4 x 54W T5 fluorescent fittings will provide a comparable illuminance on the working plane while reducing the installed electrical load, increasing lamp life, providing better colour rendering and creating opportunities for better control — resulting in an overall improvement in energy efficiency and, generally, a fast return on investment.

This was the case at the equestrian centre operated by Myerscough College near Preston, where a payback period of 1.4 years was achieved, and the scheme qualified for a Learning Skills Council grant on the basis of energy savings. Here, 48 x 400W SON fittings were replaced on a point-for-point basis by 4 x 54W Chalmor Brilliance fittings with a 24 000 h life (compared to 8000 h for SON) linked to BlueWave 2-channel lighting controllers. The lighting is controlled in relation to both occupancy and daylight levels, something that was not possible with the previous installation because of the re-strike time of SON lamps.

A further benefit of the combination of longer-life lamps and improved control, which extends lamp life even further, is that the re-lamping schedule has been extended from 0.8 years to 5.8 years. This delivers significant maintenance savings and reduces the cost of lamp disposal imposed by the WEEE regulations.

Repayments for the funding scheme for this new lighting at Ritrama are less than the cost savings being achieved.

In a similar situation at self-adhesive materials manufacturer Ritrama, the lighting upgrade was funded through energy savings, so there was no capital outlay. Instead, Chalmor funded the initial installation through its LifeSaver scheme in exchange for a pre-agreed monthly sum for three years. This sum is less than the cost savings achieved through improved efficiency, so Ritrama has been making savings from day one.

As noted above, maintenance costs can make a significant difference to the overall cost of ownership calculations. So, where maintenance costs are particularly high due to access issues and Working at Height regulations, longer lamp life is an important consideration.

When City University London replaced its existing SON and mercury light sources in its engineering laboratories it carried out a life cycle costing analysis, comparing our Endurance 60 000 h fittings with another manufacturer’s T5 fluorescent fittings. Here, lamp life was the key and, while both options offered considerable savings, it was calculated Endurance would save at least £50 000 a year, mostly on maintenance.

With existing T8 or T12 fluorescent lighting, an alternative to complete replacement is to upgrade the lamp and other components of the fitting to take advantage of the benefits of T5 technology. Here there are essentially two options, a ‘quick fix’ where a T5 lamp and connectors with integral electronic control gear are installed, with a bridge that replaces the starter and bypasses the old gear. Over a thousand T8 and T12 fittings have been replaced at the Rosie Maternity Hospital in Cambridge to save around £8000 a year with a payback of just 1.2 years.

The second option is a more engineered solution where only the body of the old fitting is retained and lamps, lamp holders and control gear are all brand new. As well as enabling ‘as-new’ performance and facilitating enhanced control through the use of dimmable control gear if required, this approach has the added benefit of a 5-year warranty for ongoing peace of mind.

Many other issues should be considered — but are beyond the scope of this short article. The important thing is to take all of the contributory factors into account, be aware of all of the options and, if necessary, call on specialist assistance.

Steven Henry is managing director of Chalmor

Chalmor Lighting
The replacement of SON lamps in this equestrian centre of Myerscough College with more efficient and dimmable lighting has reduced energy costs and also maintenance costs through the longer life of the lamps.

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