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I have performed an energy audit and want to upgrade my lighting - now what?

The missing gap between an energy assessment such as ESOS and a lighting quotation from a lighting supplier / manufacturer is referred to as a ‘Lighting Feasibility Study’.

The 'Lighting Feasibility Study', i.e. the action plan, should be ideally undertaken after an existing energy audit or an ESOS assessment has been completed, and where a client is wanting to replace or upgrade an existing lighting installation within their building.

This study assesses the lighting requirements in a particular space or entire building, enabling an accurate lighting design quotation to be prepared.

Often a client will just use the good will of a lighting manufacture to undertake a free lighting survey in a building and then install the manufacture's products. However, without looking at the rest of the market, the client may not be getting a lighting scheme which provides the best visual environment whilst being the most energy efficient.

Ideally a client should utilise the skills of an independent lighting consultant who does not represent or have any allegiance to any lighting manufactures.

This study should be performed by a qualified, independent and experienced lighting consultant, for example from the Energy Institute Register of Professional Energy Consultants (RPEC), or other relevant energy / lighting professionals such as Chartered Energy Managers, members of the Society of Light and Lighting who are holders of their association’s diploma, and members of the Institution of Lighting Professionals.

The lighting feasibility study will include all or the majority of the following aspects below in its assessment of the existing lighting system:

  • What is the overall condition and age of the existing lighting installation?
  • Does the existing lighting system still meet the latest design requirements?
  • Has the existing lighting system been maintained?
  • Are the lamps and diffusers dirty or missing?
  • An assessment of the workplace areas and availability of daylight into the space/room, including an assessment of the daylight factor

If a client decides to replace or upgrade an existing lighting installation, the feasibility study should provide:

  • A verification whether alternative lighting designs were considered and how the different types of lighting solutions meet the client’s requirements and aspirations
  • An assessment if all necessary parameters are included in the lighting design solutions include illumination levels, uniformity, etc.
  • An assessment whether and if so, what kind and quality of lighting control solutions have been included into design
  • An assessment of compliance with the Building Regulations’ energy efficiency requirements of the considered lighting design solutions
  • A verification whether a LENI calculation have been produced with accurate total lighting power, daylight factor, illuminance factor or occupancy factor
  • An assessment whether health and safety requirements have been considered, including whether the lighting design(s) meet the HSE minimum lighting design requirements
  • A verification whether the project costings include life-cycle cost analysis (LCCA) or SPP
  • A verification whether the commissioning requirements have been considered, for example, to monitor whether movement sensors or time clocks operate when they are programmed to
  • A verification whether a maintenance plan has been considered which takes into account regular lamp cleaning and replacement and whether it has been included in the life-cycle cost analysis (LCCA)
  • A verification whether sub-metering requirements have been considered?