The manufacturer of a hydrogen car unveiled in London on Tuesday will make its designs available online so the cars can be built and improved locally.

The Riversimple car can go 80km/hr (50mph) and travels 322km (200mi) per re-fuelling, with an efficiency equivalent to 300 miles to the gallon.

The cars will be leased with fuel and repair costs included, at an estimated £200 ($315) per month.

The company hopes to have the vehicles in production by 2013.