The BBC Trust is inviting feedback on plans by the corporation for a permanent free-to-view high-definition television channel. The BBC hopes to launch a permanent service on satellite, cable and where possible on terrestrial and broadband platforms. However, shortage of capacity on Freeview could disappoint consumers.

A BBC HD trial channel is currently available on satellite and cable and through a limited closed trial on terrestrial television in the London area.

The BBC is proposing to launch a permanent high-definition channel service in the next year, to be distributed on as many platforms as feasible. The single high-definition channel will be available on satellite, cable and broadband.

It will ramp up to nine hours a day from 3pm to midnight from the end of 2008. This could be extended to cover sport, music and significant national events. Due to current capacity limitations on digital terrestrial television, it will initially only be available for four hours overnight. The BBC says this will be extended if additional spectrum is secured as analogue television services are switched off.

Reception on digital terrestrial television will require new MPEG-4 receivers with digital video recorders. Manufacturers with boxes under development include ADB and Netgem and it is hoped that the availability of a high-definition service, albeit initially limited, will provide an incentive to other manufacturers.

The BBC says that while compression technology evolves, it might be necessary to use up to 15Mbps to carry a single 1080 line high-definition channel. On digital terrestrial television it could make capacity available on one 24Mbps multiplex by replacing BBC Four, BBC Parliament, two interactive streams and the looping news service overnight. As compression technology improves, it says it should be possible to carry the channel in 12Mbps by 2012.

Sky launched high-definition on satellite last year and reports that it is its fastest growing service, with nearly a quarter of a million homes signing up in the last year. Nevertheless, the United Kingdom and Europe in general are trailing many other countries in adoption.

Less than 5% of BBC television output was produced in high definition in the year from 2005 to 2006. It is estimated this will ramp up to around 2,000 hours in 2010.

Forecasts provided by the BBC suggest a population of 3.8 households able to receive high definition in the United Kingdom in 2010, rising to between 8.8 and 9.5 million in 2012. By that time, in its most optimistic scenario, the BBC suggests that there will be 2 million high-definition terrestrial receivers but only half a million homes receiving high-definition IPTV services over broadband.

The public value test proposals contain a range of supporting research, but ironically many of the financial references are redacted. The test of public value is therefore to be taken on trust.

Based on the results of market research, few would argue that the BBC should be leading the way in high-definition. The real question for the public will be whether four hours overnight on Freeview represents good value.

In parallel, the BBC has recently presented proposals for a Freesat service which could make its high-definition channel freely available on satellite which would undoubtedly stimulate demand.

The communications regulator Ofcom will conduct a market impact analysis to contribute to the public value test by the BBC Trust. Both BBC and Ofcom are inviting responses to the proposals, details of which are available on the BBC Trust web site.

Meanwhile, Michael Grade, former chairman of the BBC Governors, now executive chairman and chief executive of commercial broadcaster ITV, has called for a loan of additional spectrum for high-definition.

“In due course, once HD compatible boxes are sufficiently widespread, we will give the loaned spectrum back and it can be auctioned,” he told a meeting of the Royal Television Society attended by culture secretary Tessa Jowell.

He said that by the end of the decade 80% of households will have an HD Ready set. “The warning lights for policy makers should be flashing red.” He said market research suggested that most consumers buying high-definition sets expect to receive services via Freeview in high-definition in the future. “The trouble is that in due course these people are likely to be bitterly disappointed.”