South Wales Police has replaced existing T8 lighting in its Main HQ Building with more energy efficient T5 lighting. T5 retrofit lighting is a cost effective method of replacing T8 and T12 lighting. T8 and T12 lighting is, on average, 52 per cent more expensive to run that the T5 equivalent.
The use of T5 tubes (rather than T8 or T12) allows the tubes to be fitted into smaller spaces, and the smaller light source also enables more accurate control of beam direction by means of optics (reflectors and lenses in the luminaire). It is notable for its lumens-per-watt efficiency, due to its peak light output occurring at 35°C (95°F) air temperature.
The T5 lamp has low mercury content and has a coating on the inside ofthe glass wall. This coating stops the glass and phosphors from absorbing mercury. This barrier coating reduces the amount of mercury needed from approximately 15 mg to 3 mg per lamp. Since mercury absorption causes the lamp's light output to depreciate over its life, the coating helps to keep light levels much closer to initial output.
This initiative has resulted in savings of £7,500 and 42 Tonnes of Co2 per annum for the South Wales Police. The capital cost was £26,000 and this is expected to be recovered within three to four years.
Name: Dan Ferris
Title/role: Estates Manager - Facilities
Organisation: South Wales Police
Telephone: 01656 305 943