I see a day, possibly two or three decades from now, when all street lighting is LED based, controlled remotely via a wireless signal from a central location, and mostly self-powered.
Power for the lights will come from a battery bank, backed up by the main power grid. The battery for each street lamp will be charged by a vertical wind turbines mounted on the light poles and a small, solar array attached to the top of the pole.
Each LED street lamp transmits a signal back to a central control system that monitors battery level, battery health, and whether the LED lights need any maintenance.
Each street lamp can also monitor its own light output via a photo receptor that will detect when the LED itself fails, so that a maintenance crew can be scheduled to come out an repair it.
I don’t expect to see street lighting like this until 2020 or even 2030 at the earliest.