However, regardless of this, the spectrum that we are auctioning could never have been used for 4G until this year, not least because the digital switchover needed to complete first to create the 800 MHz capacity".
Ennals said coverage was one of the "five Cs" needed to make digital switchover a reality, along with in-car radio, affordable and accessible consumer electronics, quality content and the right communications message.
Ashley Tabor, founder of the UK's biggest commercial radio company, Global Radio, has criticised the BBC for dragging its feet on digital radio and questioned the need for switchover.
White space uses the spare spectrum in the UHF band, no longer needed for television broadcasts following the digital switchover.
This is the current position of Ofcom and the government, and their preferred source of funding for non-BBC PSB, over and above what Channel 4 delivers, is the part of the licence fee earmarked for digital switchover assistance, which will not be needed for that purpose after 2012.
The BBC's director of radio, Helen Boaden, said there needed to be a "really huge growth" in in-car digital radio for switchover to happen.
The green investment bank has come up with a financial proposition to spur the switchover, by which local authorities and other public bodies can receive the cash needed for the new lights upfront, to be paid back over time as they realise the efficiency savings from the new technology.
Mr Bryant said S4C needed to make changes to head off the threat of declining revenues and the migration of viewers after digital switchover to Channel 4. S4C is broadcast in place of Channel 4 on digital terrestrial analogue TV in Wales.
A Green Alliance report compared the Green Deal with the recent digital TV switchover and concluded: "There is a huge risk that the government's current plans for communications won't deliver the levels of take-up needed to make sure the Green Deal (is) a success".
He added: "What is absolutely clear is that continuing current purchase trends will not lead to switchover in our lifetime; we need a step change in approach.
