OTTAWA -- Transport Canada's long-awaited studies on mandatory speed limiters have been released and they apparently show that capping the speed of large commercial trucks at 105 km/h will have positive environmental results for the nation.

Transport Canada, with the assistance of a steering committee representing British Columbia, Manitoba, Ontario, Quebec and New Brunswick, commissioned a number of studies to review the implications of a national speed limiter requirement from a safety, environmental, economic and operational perspective.

The report reveals that speed limiters on large trucks could result in 228.6 million liters of diesel fuel saved, representing 1.4 percent of the total on-road diesel consumed in 2006.

Ontario and Quebec -- both of which have already committed to speed limiter legislation in advance of the federal studies -- would account for 64 percent of the estimated national savings.

"The Government of Canada supports the use of speed limiters on large commercial trucks because they help reduce greenhouse gas emissions and improve fuel economy," said Transport Minister Lawrence Cannon.

Ottawa weighs in: We like speed limiters

Each province will be responsible for mandating speed limiter rules if they so choose. But while local trucking association lobbying has convinced Ontario and Quebec to lead the charge, other provinces are lukewarm to the idea. Alberta, in fact, has declared it will not adopt such legislation.

Unlike previous studies attempting to measure the environmental benefits of mandatory speed limiters, the recent Transport Canada reports are reportedly more far-reaching.

In a recent Today's Trucking article, Transport Canada senior research analyst Andrew Spoerri confirmed that the methodology used by the department drastically improved over a previous GHG discussion paper used by the Ontario Trucking Association to advance the plan.

This time, explained Spoerri, researchers collected actual speed distribution data from weigh-in-motion sites around the country as opposed to assigning a GHG-saving figure based on a theoretical average speed for all trucks. That data was averaged to produce a speed distribution profile for each province.

Furthermore, the new study isolates highway systems above 100 km/h -- in other words, where speed limiters would be a factor.