Street lights that can be dimmed to conserve power are to be used across central London to cut energy bills and lower carbon emissions.
More than 14,000 lights will be converted as part of Westminster City Council's Smart Lights project.
The council hopes to save £8.4m over the 20-year lifespan of the lights, through reduced energy costs and maintenance requirements.
The brightness of the lights will be monitored by the council's CCTV system.
According to the council, dimming the lights at less busy times makes an energy saving of about 20%.
By working at 75% capacity it ensures energy is not wasted and the units require less maintenance, it said.
The council expects to save £420,000-a-year, after the cost of setting up the scheme is recovered.
Councillor Ed Argar, from Westminster City Council, said: "It makes no sense to be wasting money and energy with lights burning brightly at all hours.
"This is one of many ways Westminster is looking to save money by innovative schemes that benefit everybody.
"It keeps the lights on, it saves money for the taxpayer and it build a greener city. "
The lamps can be controlled remotely and at the touch of a button lights which have been dimmed can be brought back to full intensity.
The council is also developing a system which would allow the lights to be controlled through the use of text messages.
Police officers or members of Westminster's street team would then be able to text the control centre and ask for lights to be made brighter if more people are using the area.