Wellington, June 29 NZPA - A proposal to increase the length of trucks carrying empty containers by 2 metres could make a big difference to the movement of containers around New Zealand.

The movement of empty containers is often cited as a big cost for the economy by executives in the transport industry.

Containers are emptied in Auckland where most imports end up and have to be transported around the country to be filled with products for export.

Transport Minister Steven Joyce is consulting on a plan to create a permit system allowing heavier trucks. Trucks would be allowed to carry up to 53 tonnes, up from the current 44 tonnes, subject to the permit process.

Ian Clark, project manager at the Ministry of Transport, said the changes would also allow trucks to increase in length by 2m to 22m. This was specifically for empty containers where there was no weight issue.

Currently trucks can carry two 20 foot containers or one 40 foot container.

"If we add 2m to the vehicle they can carry three 20 foot containers, or a 40 foot and a 20 foot container," he said.

This could reduce the number of truck trips involving empty containers by a third, providing a big productivity increase for the economy.

A figure of 7000 empty container movements a day from Ports of Auckland is being talked about in the industry but it has not been verified by the department.

Mr Joyce said a trial of heavier trucks that ran from last year showed productivity increased between 10 and 20 percent, trip numbers reduced by 16 percent and fuel use dropped 20 percent.

Reduced freight costs would help exporters and New Zealand "grow faster out of the current global recession".

It would also mean fewer trucks on the road which would ease congestion and frustration, Mr Joyce said.

The Land Transport Rule -- Vehicle Dimensions and Mass Amendment, subject to consultation, could be signed off by the end of 2009 with application for permits starting in 2010, Mr Joyce said.