Sniffer dog Jac works for SP Energy Networks helping to keep lights on in Scotland

A dog has been trained to sniff out faults in power networks that lie deep underground to help keep electricity flowing this winter.

The springer spaniel, named Jac, has been trained by SP Energy Networks (SPEN) at a substation in the town of Renfrew near Glasgow.

The dog is able to smell oil and hydrocarbon gases through earth and tarmac.

He uses his front paw to pinpoint the site of a fault, saving engineers from digging holes to find the source of the problem.

Jac has had a 100% success rate in finding faults on 30 occasions, according to Scott Mathieson, planning and regulation director at SPEN.

SPEN is responsible for 65,000 miles of network and 30,000 substations.

Cables are typically buried 40cm to 80cm underground, but Jac has been able to find faults two metres (about 6ft 7in) deep.

"Part of keeping the lights on in an electricity network involves investing in innovation and technology," Mr Mathieson said.

"We're used to using laser technology, flying the network with drones, but Jac adds to our armoury significantly.

"He is a sniffer dog and we've been piloting using Jac to help us detect cable faults in particular."

Mr Mathieson explained: "So when cables fail, if they're oil-filled, they let off some oil that lets off hydrocarbon gases or the insulation breaking down lets particulate levels of hydrocarbons off.

"Jac is a springer spaniel whose sense of smell is thousands of times more effective than a human being, and he can detect exactly where the cables have a weakness in them.

"The benefit of that is that we can repair the cable actually before it fails and improve customer experiences."