Turning Off the lights Simples!!!

The Switch Person leaves the room – turn off the lights Its that simple but! So why do lights get left on? Who is responsible?

Automation Time switch Daylight sensor Motion sensor DAHLI

Time switch Pros Turns the lights off between set periods Simple to wire or use cheap Cons Can be difficult to programme Not very flexible Can use electricity (typical 1 watt)

Daylight sensor Pros Lights only work when dark Simple to wire Cheap Cons Have to be positioned correctly Not very flexible Uses electricity (typical 1 watt)

Motion Sensors Three main types PIR, Microwave, Ultrasonic Pros Work only when area occupied More expensive May have daylight switching Cons Need to be selected, installed and commissioned carefully Can be complicated to wire Uses electricity (1 to 10 watts)

Digital Addressable Lighting Interface The All singing dancing lighting control Pros Can do everything the previous technologies and more Scene setting, variable light output, automatic testing etc. Cons Need to be selected, installed and commissioned carefully Very complicated wiring Can have complicated local controls Very expensive Usually needs an intranet connection Uses electricity (? Watt)

The balance All these technologies have a theme: they use electricity. 1 watt is constant and there are 8760 hours a year. 1 watt x 8760 = 8.76kWh (4.59 kgCO 2e ) 60w lamp for 146 hours 30w CFL for 292 hours 16w LED for 547 So it is important to do the simple calculation both environmentally and financially Should we ever use DALI

Absence or Presence detection What's the difference (presence no local switch, absence needs a switch) Why you should nearly always use absence detection Using a local switch to turn off the detector will save energy.

Conclusion Use the correct technology if needed Check the numbers Badly designed or installed systems will increase energy consumption I still think the humble switch is best Thank you