Choose LED lights
Bristol Energy Network found that if the whole city switched to LEDs, it would represent a saving of almost 5% of the whole city’s annual carbon emissions!
There are different options so you’ll need to do a bit of research to make the right choice for the different rooms in your house. Energy Saving Trust has some handy tips.
Also, there’s a bit more of an upfront cost but you’ll easily make the money back with cheaper bills.