Case Study Five

HM Customs and Excise

With over fifteen years in the energy saving lighting controls market, Setsquare Limited was chosen by HM Customs and Excise to provide the system to be installed at their London Headquarters. The InfraPOD system selected has proved itself time and again to be both user friendly and efficient and achieved a three year payback for Customs and Excise, including installation.

A monitored trial by project managers WS Atkins shows a 77% reduction in energy usage, falling from 116.7 kWh in the pre  install period to 26.9 kWhrs in the monitored period.  The system was installed initially on half a floor of Customs and Excise Headquarters, New Kings Beam House.  "We have a significant property portfolio and we were keen to have a long term evaluation before applying controls to other areas".says John Cole, Environmental Policy Manager for Customs.   "On the strength of the monitoring figures we have now proceeded with all the other C & E occupied areas in this building."

WS Atkins found that Setsquare's InfraPOD system exactly met Customs and Excise's requirement of a simple, unobtrusive system with user control. John Cole expiains "The existing timed reset control system in the building was ineffective and had been largely over ridden as there was no local control.  We were keen to replace this with a simple system, based on local switches, which would give staff control over their own lighting, but with an automatic over ride if lights were not switched off.

WS Atkins decided hour run meters were the best monitoring option long term, as there were 38 areas in the initial trial. Each area comprises of a bay with control, sensors and demand switch. The total load from the monitored area was 9.3 kW and the saving in the monitored period was 90kWhrs, from 116.7kWhrs to 26.9kWhrs a reduction of 77% in energy usage.

InfraPOD   is a modular system, with a power supply and switching unit for each area located at the switchboard and a series of low voltage sensors in the work area. Highly sensitive infra red sensor are used to detect staff in the work area whilst a photocell monitors the light level. A low voltage momentary demand switch was also mounted on the wall in each area. Lights are initially activated by staff pressing the demand switch and they remain on as long as the sensors register people in that area. When there are high levels of daylight, lights are held off as the photocell is dominant. If however staff want the lights on regardless of the level of daylight, the photocell can be over ridden by holding down the demand switch. They will switch off automatically when sensors fail to register people in the area. This system is effective in reducing energy usage while still allowing staff control over lighting at their own work stations. "Use of the demand switch has led to increased energy savings as many staff prefer not to use lights until they have to and not just for PC work" says John Cole "In the window bays most lights aren't switched on until late afternoon or not at all."