Electricity Savings Calculator


To fill out this form simply answer the five questions on the left then click calculate. We have included some hints on the right to help.


1. We have bulbs in our room.
2. They are currently rated at Watts
3. We would like to replace them with LEDs rated at Watts
4. We are paying pence per kilowatt hour for our electricity
5. These bulbs are on for hours a day
You will save per year
You will save kg of CO2 a year
1. You should only work on one type of bulb at a time in this form.
2. The bulb power in watts will be a number followed by the letter 'W' on the bulb.
3. If you do not know the power use 3W for gentle light and 5W for higher light levels.
4. If you do not know your own rate then use 12 pence


  • This form should be used as a guide and whilst we have made every effort to ensure its accuracy we take no responsibility for your specific circumstances.
  • We have used the the published Carbon Trust rates of 55.4g/kW.h for CO2 production during UK mains electricity generation.