https://www.bbc.co.uk/news/articles/cwz0vxl21m3jo
This bloke is wandering around in the dark to save money. No where in the article does it mention how much it actually cost to run a light.
A standard 6w modern bulb costs less than 2p for ten hours. I simply don't believe this is is anyway cost effective.
My mother in law had a fall trying to save money by not switching lights on, when I asked her how much she thought it cost, she reckoned about 50p
Articles like this are part of the problem.