One of the major causes of always-on street lighting are the electricity companies who offer local authorities bargain rates overnight in order to smooth usage.

One of the major causes of always-on street lighting are the electricity companies who offer local authorities bargain rates overnight in order to smooth usage. My local authority looked at turning-off street lights from 02:00 to 06:00 each day ( as they did before 1968 ) but calculated that the doubled cycle load on the sodium lights would lead to more failures. Given that unknown cost, versus fractions of a penny in electricity per light per night, they elected to keep the lights lit. So now we have more LED lights and always-lit.