Lighting design and controls improve working conditions and cut energy

Lighting systems provide tremendous opportunity for energy savings in operations which run 24 hours a day, seven days a week, year round. The Quesnel River Pulp Mill in Quesnel, BC is a prime example of such an operation.


In search of quantifiable estimates of savings at the Quesnel River Pulp Mill, BC Hydro turned to Prism to supply a detailed Lighting Review Report. Prism was tasked with:

  • Analyzing the current lighting systems
  • Providing an estimate of existing electrical energy consumption
  • Proposing measures that would save energy while maintaining a reasonable payback
  • Recommending cost effective retrofits and control upgrades


At the mill site, Prism conducted a detailed audit of all lighting and used a light meter to take representative light level readings from the plant and office areas. The results of these readings were used to determine which areas were over or under lit, and identify opportunities where lighting upgrades and control systems (such as occupancy and daylight sensors) could be implemented. It was found that while the plant was running 24 hours a day, many spaces were infrequently occupied. Lighting in other areas was found to be inadequate for workers.

Prism estimated the current energy use by analyzing the number and specific types of lighting used in the mill, along with their approximate hours of operation. From the overall data collected, Prism presented a number of options for the lighting upgrade that:

  • reduced energy use and operating costs
  • provided lighting levels suitable for the tasks performed
  • provided a renewal of lighting systems
  • added controls for switching


Prism's detailed audit estimated that current annual lighting electrical costs were over $100,000. If the recommended measures outlined below were implemented, an estimated $20,000 of annual electrical cost savings could be achieved:

  • Replacing T12 fluorescent lamps with more efficient T8 lamps
  • Installing occupancy sensors to prevent unoccupied spaces from remaining lit
  • Installing photocells or manually controlled switches for exterior lighting systems to reduce hours of operation

The total cost of implementing these measures was estimated at $55,830, with a 2.8 year payback. Furthermore, it was found that additional savings of up to $12,390 could be achieved if the dim plant luminaires and warehouse high pressure sodium (HPS) luminaires were replaced with induction lighting.