National Grid should not have ended a consultation on plans to route underground or overhead power cables across Shropshire and Mid Wales until the results of an independent study on costs had been published, campaigners said today.

The company has been accused of attempting to bury a report which could reveal the cost of running underground power cables is less expensive than they claim.

The Campaign to Protect Rural England and other environmental bodies said today the consultation should have been extended until after the report is published.

John Day, centre, presents the petition to Christine Chapman AM, Chair of the Petitions Committee, with Russell George, AM for Montgomeryshire and William Powell AM, committee member and AM for Mid and West Wales

But it closed on Monday.

It comes as a petition of more than 3,200 names opposed to National Grid plans for a substation and massive pylons across Mid Wales was handed in to the Welsh Assembly yesterday.

John Day, from Bwlch-yfridd, near Newtown, went to the Assembly’s headquarters in Cardiff Bay where he handed in the petition calling for the Assembly Government to change its policy on windfarms. The petition was signed by 3,249 people.

National Grid has come under fire from the CPRE after power bosses agreed to fund an independent study by energy consultancy KEMA into the expense of installing new high voltage power cables underground, sub-sea or as overhead lines.

It was due in January but KEMA said they had not been given the necessary data to complete it.

KEMA has now been removed from the project with the report five months late.

Paul Miner, for CPRE, said: “We are being asked to accept at least a thousand more pylons in the British countryside on the strength of cost estimates provided solely by National Grid.

“The current situation seems to suggest National Grid is happy to bury this report if it helps them to avoid burying their cables.”

Jane Taylor, for National Grid, said: “We gave our evidence to the study along wi-th other organisations both in this country and abroad.

“The evidence is available to view on our website. The important thing to remember is that the technology we will use for this project has not been decided.”

By Chris Burn and Andrew Morris