This source suggests that the average UK household uses 4400kWh of electricity per year, which averages at around 12kWh per day. It only takes 20 columns fitted with 600w SON lanterns, excluding gear losses, to be switched on for one hour per day to match the same power consumption as the average British household. The old 1970s lighting on the M1 in Northamptonshire features around 40 columns per mile. I've counted, and that means column spacings are around 45m. Column spacings that the HA uses for 15m columns nowadays are typically 50m, so not much greater. Hence, one mile of 600w SON switched on for one hour per day uses around the same amount of energy as two households per day by my reckoning, excluding gear losses. And the government has the front to tell us to save energy.
phosco152, please check my calculations to make sure they are correct so that I don't end up with egg on my face!
20 columns (1/2 a miles worth) at 600w each is 12Kw load so for 1 hour of use that is 12Kwh, so over a year that is 4380 Kwh. So yes about the same as the alleged household use for 1 year. However if they are twin brackets that is 48Kw load or about
4 houses per mile for 1 hours use! It is worse than that if you include gear losses.
This is absolutely appalling and why further lighting of motorways 24/7 cannot be justified. Some of the busiest sections of the M3 and M4 are unlit for instance. This environmental impact cannot be justified in the name of reducing accidents especially when vehicle safety is improving all the time.
To validate the household figure - I pay my electricity by direct debit. They have just calculated my payments for the next year based on a usage of 2280 Kwh. That should have been based on last years usage - I've been in the house more than a year now. I am not on a gas supply so have oil heating and use electricity for cooking/electric shower etc. I am the only occupant, so assuming 2 people in the household, energy consumption would be perhaps 30-40% more ( 2 people doesn't
necessarily mean double the lights for instance..), so the quoted figure of 4400 kWh is probably about right.