The official consultation on the rollout of smart metering technology for domestic electricity and gas supply started last week.

Smart meters display real-time information on energy use, helping householders monitor use and eliminating the need for inaccurate, estimated bills.

But government proposals to distribute free low-tech clip-on electricity metering devices will delay the rollout of the upgraded infrastructure, say energy industry groups.

The plan to give Electricity Display Devices (EDDs) to all UK households was included in the same Energy White Paper published in May that launched the smart meter consultation.

But industry groups say EDDs are a short-term solution that will distract attention from the necessary major investment.

'Clamp-on devices do not deliver smart meter benefits,' said Energywatch campaign head Jonathan Stear.

'They are poor substitutes and waste resources.'

The infrastructure upgrade required by smart meters could be completed within 10 years, but only with the help of a government mandate, says the Energy Retail Association (ERA).

'Smart meters will allow the industry to evolve, but they require massive investment,' said an ERA spokeswoman.

'It is the same level of transformation as the digital switchover in the broadcast sector.'