People are being put through their paces at the Royal London Hospital this-afternoon to show how much energy it takes to power domestic gadgets.

They are being invited to step into a rowing machine or mount a bike wired up to generate electricity being fed into iPads and domestic appliances.

It is all part of today’s NHS Sustainable Day of Action which staff at the new hospital complex are taking part in, including planting 10 saplings.

The national campaign is being launched by actor and TV presenter Stephen Fry, Health Minister Simon Burns and NHS Chief Sir David Nicholson to promote a sustainable health services.

The Royal London’s NHS trust has recently reduced its water usage by nearly a third to help shrink the hospital’s carbon footprint.