Power suppliers could be required to clamp down on electricity theft under new rules proposed by the regulator Ofgem.
The supply industry is subjected to up to 25,000 cases of electricity theft every year, costing consumers at least £200m, or £7 per electricity customer, Ofgem said, with up to a third of the volume of electricity stolen each year used to power cannabis farms.
Now Ofgem wants new rules to be brought in to reduce the amount of theft, with fines for suppliers who do not comply by bringing in measures to detect, investigate and prevent cases.
Under the proposals, suppliers would also have to set up a national theft risk assessment service to help them target premises where there are strong suspicions that electricity is being stolen.
"Ofgem wants to make sure that consumers are paying no more than they need to for their electricity, and lives are not put at risk,” Ofgem's chief executive Andrew Wright says.
"It's critical that suppliers do all they can to clamp down on electricity theft. This is why Ofgem is introducing new rules to encourage better theft detection.
"The reforms build on similar obligations we introduced at the start of this year for suppliers to address gas theft more vigorously. All these measures will help to improve the confidence of consumers, who want reassurance that the energy market is fair."
Suppliers and network companies would have to create an industry code of practice governing how theft investigations should be carried out, to ensure a consistent approach across the industry.
They would have to share best practice methods and knowledge across the industry about how cases of theft are identified, and liaise with agencies such as the police and Home Office over how to tackle electricity theft relating to cannabis farms, Ofgem suggested.
A 24-hour hotline would also be introduced to allow customers to report suspected electricity theft and suppliers are being asked to propose a financial incentive scheme to Ofgem that would encourage them to detect and prevent theft.
Energy UK, the trade association of the energy industry which represents more than 80 companies, welcomed the proposals.
A spokesman said: "Ofgem's consultation is a positive move to cut down crime, and we look forward to working closely with them, and others in the Industry, on this.
"Electricity theft is dangerous and illegal. Contact with live electricity cables can kill and tampered meters cause fires. Electricity theft also costs honest customers money which is why energy companies take this and gas theft very seriously .
"Every year our members detect and prosecute criminals. When energy companies find electricity thieves, they will prosecute."
An initial consultation on Ofgem's proposals has been published today and the deadline for responses is August 28.
Ofgem expects to have a licence condition for suppliers in place by early next year, with the theft risk assessment service running in early 2015.