BBC Click's Jen Copestake has been given exclusive access to the test flights of a drone powered by a hydrogen fuel cell.

Intelligent Energy's fuel cell can power a modified drone for up to two hours - about six times longer than the average with a normal battery.

Refuelling with compressed hydrogen takes a few minutes compared to recharging a battery.

The company sees its drones being primarily used in industry for agriculture and oil and gas mapping, before being offered as a consumer product.

Intelligent Energy expects to have the fuel cells ready for commercial use in the next year.

More at BBC.com/Click and @BBCClick.