Melbourne, Nov 5 Laser-powered space elevators are taking part in a NASA-backed competition in the Mojave Desert.

The Space Elevator Games are held to find the best way to send a robotic platform into space while still tethered to the Earth.

Each competitor uses a strong laser - or "power beam" - to send energy to a solar panel on the elevator platform, giving it enough juice to climb a 1km cable.

And the challenge is for the platform to climb the cable, stretched between the ground and a helicopter in the sky, at a rate of 5m per second, reports News.com.au.

While no one has completed this challenge for the past three years, experts are seriously considering the concept of space elevator-which was once a realm of science fiction.

It doesn't rely on rocket power, which is mostly used to leave the Earth's atmosphere, and could help transport cargo.

NASA has even reportedly considered the ocean off Western Australia as a launch site for a space elevator.

According to experts, space elevators pose an engineering problem, as the theoretical model relies on a tethering cable that needs to be 150 times stronger than steel.

NASA has backed the 2 million dollars competition, run by the non-profit Spaceward Foundation, since 2004. (ANI)