United Kingdom, March 4 -- Lenovo's new laptop charges up using energy from the Sun.

The Chinese tech giant's new device has solar panels built into the casing, which allows the battery to fill back up when the user is outdoors.

Lenovo believes that people will get an hour of video playback from only 20 minutes of solar charging.

The firm's new Lenovo Yoga Solar PC was revealed at the Mobile World Congress event in Barcelona.

The "ultra-slim" laptop measures just 15mm in thickness and is light at 1.22 kilos, the equivalent of about five iPhones.

The device is only a concept for now but could end up on sale one day.

Lenovo say that the idea is that users will be able to "turn any space - indoors or outdoors - into a productive worksp...