Thoth Technology, a Canadian technology company, has got patent for a space elevator. The company says the 12 mile-high structure would help free from the dependence on rockets for launching astronauts into space.

The patent is meant for an inflatable, pneumatically pressured tower stretching 12.5 miles high. A liftoff point to space would be served by the top of the so-called space elevator. As a result, it would become possible to bring down usage of fuel by more than 30%.

"Astronauts would ascend to (12 miles) by electrical elevator. From the top of the tower, space planes will launch in a single stage to orbit, returning to the top of the tower for refueling and reflight", inventor Brendan Quine says in the release.

Ishwar Puri, dean of engineering at McMaster University in Hamilton, Ontario, Canada, says the concept of the tower holds great promises, but making it a reality is a big challenge.

Engineers are required to maintain the structural integrity of this tower and avoid the situation where it might snap into two.

Finding the right materials, keeping it stable and providing the energy required to operate the tower are the three main challenges.

The tower would stretch 20 times higher than Dubai's Burj Khalifa, which is currently crowned as the world's tallest building, with 830m into the sky.

Russian scientist Konstantin Tsiolkovsky was the first to propose the idea of the space elevator in 1895. He drew his inspiration from the Eiffel Tower in Paris.