Astronauts have ventured out on a spacewalk to fit the International Space Station (ISS) with powerful new solar panels to handle the growing electrical demands from upcoming visitors.

It is the first of a series of spacewalks to equip the aging orbital outpost with smaller but stronger solar wings. The electrical boost is needed to accommodate the paying passengers expected to drop by, beginning with a Russian film crew this autumn.

Nasa put extra safety precautions in place as French astronaut Thomas Pesquet and US astronaut Shane Kimbrough worked on the station’s primary power grid, to avoid an electrical shock.

The pair had to conduct the most hazardous parts of the spacewalk on the night-time side of Earth, to prevent the station’s old solar panels from soaking up sunlight and generating power. Metal surfaces on their spacesuits were covered to avoid any contact.

The astronauts during their spacewalk
The astronauts had to lug the folded-up solar wing to the work site (NASA via AP)

Launched by SpaceX earlier this month, the first of these new solar panels was going to be installed alongside the station’s oldest electricity-producing wings, in continuous operation for more than 20 years.

The astronauts had to lug the folded-up solar wing, which is 10-feet long, by four-feet wide and two-and-a-half-feet thick — to the work site on the far left end of the station.

Once anchored in place, the solar panel was designed to roll out like a red carpet. It was expected to take six minutes to extend to its full 63-feet in length.

Mr Pesquet and Mr Kimbrough will go back out again on Sunday to install a second solar panel.

Four more will be launched to re-energise the space station.

Nasa wants to keep the space station churning out science research through this decade, and space tourists will further tax the power system.

A Russian film director and actress are due to visit in October for filming, followed by wealthy entrepreneurs launching from
Kazakhstan and Cape Canaveral as part of a push to open up the private space market.

Nasa’s space station programme manager Joel Montalbano said these visitors would undergo rigorous training before lift-off.