Street lamps do not consume a great deal of electricity. Unfortunately, as there are many of them this rapidly builds up.
A new turbine that spins horizontally rather than vertically may make a big difference. Apart from anything, these turbines will be forced to turn as traffic passes, guaranteeing plenty of electricity each day. While these turbines are never going to make large amounts of power, given the large number of street lamps around the UK, it could generate a lot of power (it is estimated that it could create 6mw of power a day, enough to power a small village.