The University of Saskatchewan's 'climber,' or space elevator prototype, won the competition last year but not the cash prize. ((University of Saskatchewan Space Design Team))

Five Canadian teams are trying to build an elevator capable of transporting people from the ground up to a space orbit, for an upcoming NASA-sponsored contest.

The third annual Space Elevator Competition features more than 20 teams from around the globe and takes place Oct. 19-21 in Salt Lake City, Utah.

The Canadian teams competing in 2007 are from five universities: Kingston, Ont.-based Queen's University, University of British Columbia, Montreal-based McGill University, University of Alberta and the University of Saskatchewan.

The space elevator doesn't use rocket propulsion. It's basically a physical stationary tether between the ground and an object in space, and a set of vehicles that can travel to space and back, moving on the tether using electric motors.

Spaceward Foundation, whichis sponsoring the event,says on its website that the term "elevator" is a bit misleading, since it's better described as a much larger gondola-type ski lift that moves vertically.

To claim the prize money, the winning team must come up with the best design that also passes a stringent setof requirements — which are increased each year of the contest.

University of Saskatchewan had strong showing

In both 2005 and 2006, the University of Saskatchewan's team placed first in the competition, making it one of thisyear'sfavourites.Although it was the best performerin 2006, it narrowly missed getting any prize money.

"We were just 0.4 metres per second too slow from winning the $150,000.We more than doubled the performance of any other team last year as well. We were so close, it was a little frustrating," Clayton Ruszkowski, leader of the University of Saskatchewan team, told CBC News.

About 30 people are working on this year's project, which, compared to last year, has garnered much more support and corporate backing, he said.

For 2007, the minimum requirements to win the $500,000 prize havedoubled.

"Instead of 200 feet, it's 400 feet that we have to climb, and the minimum speed is two metres per second instead of one metre per second. That makes the engineering difficult and more intense. Designing a more powerful system brings costs up. We've been working hard for the pasteight months, and we are going to be ready for this year," said Ruszkowski.

He believes that the biggest challenge for all the teams, including his, will be developing the elevator's power source.

"This year we are using a very powerful laser system that will beam laser lights. It's much more focused," he said.

And tracking the elevator is not an easy feat, he added.

"It's like trying to point a laser pointer at a target 200 feet away and keep it steady."

"From what we have seen of the teams so far, we are looking forward to an exciting race to the finish this year," said Ben Shelef, CEO of the Spaceward Foundation. "Third year's a charm — we expect to be able to award the prize purse this year."

Prize money totals $1M US

The contest is divided into two competitions, with each having a $500,000 US prize provided by NASA. The more visible challenge is the attempt to build the best possible space elevator climber prototype, which is where the Canadian teams are competing.

The other challenge is to develop the material that makes up the tether on which the elevator rides. The winner of the challenge must present a tether that is at least 50 per cent better than last year's offering.

"Compared to the best commercially available tether, we need a material that is almost 25 times better — about as great a leap as from wood to metal. Quite a tall order," states the Spaceward Foundation's website.

The space elevator competition's prize purse is funded through Centennial Challenges, whichisNASA's prize contest program.