Streetlights controlled by iPads that tell engineers when they are broken will save Westminster Council �420,000 a year.

The “smart” light system will be installed right across Westminster’s 14,000 street lights over the next four years after a successful �3.25million pilot scheme.

The council expects the lights will have paid for themselves within seven years through energy and maintenance savings.

While other councils consider switching off street lights to save energy and cut costs, it was not considered appropriate in Westminster – so it plumped for a “third way”.

City management boss Cllr Ed Argar said: “This provides people in Westminster with the light they require to feel secure and continue to function safely in a 24-hour city.

“But it also will reduce our energy bill by nearly �1million every two years – a huge saving that we can pass onto the taxpayer.”