Carbon Footprint- Putting energy saving light bulbs into perspective

In a previous post I reviewed the impact of changing from traditional filament incandescent light bulbs to energy saving light bulbs on the carbon footprint. In broad terms then if you use a 100 watt bulb for 4 hours a day then changing this single bulb to an energy saving light bulb will save around 100kg in C02 emissions!! Now you might quite correctly say; ” Is that significant? ” or indeed “Is that worth worrying about? ” or ” Well if I just start walking the children to school is that not better?” . Here I will try to put this into perspective so you can make an educated judgement yourself.

Carbon Footprint comparison for Transportation

The reason a light bulb has an effect on your carbon footprint is because electricity generation is normally gas or oil fired and this produces a significant amount of C02. So the obvious question is why do we not compare the C02 generated to private and public transportation which certainly for cars and planes results in the direct emissions of C02 into the atmosphere.

The Family Car
So lets say for example that you own a Ford Focus C-Max 1.8 (125PS) built in 2005, which is a fairly decent family car. You would need to drive this vehicle for approximately 330 miles for it to emit 100kg of C02 into the atmosphere. So comparing that to your single light bulb you would need to stop driving the car of the order of 1 mile per day.

The Train
Public transport is certainly a more efficient way to travel from an environmental perspective but the calculation is more complex because it clearly depends on how many people are on the train and the efficiency of that particular train. However accordingly to published statistics you would need to travel of the order of 1000 miles on the train for 100 kg of C02 to be created.

Travelling by Aeroplane
Planes certainly create a lot of C02 but they are a relatively efficient way of transport from a C02 perspective when they are full when compared to the passenger car. To create 100kg of C02 you would need to fly from London to Manchester and back.

Household Electrical Appliance Carbon Footprint Comparison

So that looks at the transportation comparison but you might say for example “Well should I stop using my dishwasher as often or certainly make sure that it is always full when I turn it on?” To look at this we need to compare the electricity consumption of these appliances to your electric light bulb.

The 100 watt light bulb when used for 4 hours per day will consume 146kW of electricity in a year which would cost £19, assuming you pay 13p/ kWhour for electricity.

A dishwaher will use around 2kW for each use so if you use it once every 5 days then this uses the same amount as your 100 watt light bulb.
A washing machine uses around 2.5kW for each use so in a similar way of you use this once every 6 days then it will use approximately the same amount  of electricity as your 100 watt light bulb.

Now this is quite stagering and really emphasises how much electicity traditional light bulbs use and whilst it does make sence to use your washing machine and dishwasher effectively you can make a far more significant impact by changing you light bulbs. When it comes to transprotation I will let you be the judge but hope this data should help you in making a more informed choice.