Their firms are hobbled by the costs of building their own infrastructure: backup generators, water-treatment plants and fleets of buses to ferry staff to work.

ECONOMIST: India's economy

To compensate for deficient public utilities, the company operates its own fleet of buses and has its own satellite links, power generators and water recycling plants.

FORBES: Passage To India

It also develops its own PEM (proton exchange membrane) fuel cell generators and has a growing business in China, where it will power the buses for the 2008 Beijing Olympics.

FORBES: Fueling Speculation

As well as two fuel-cell systems for vehicles (one for cars, another for buses and lorries), there are separate systems for large and small generators fridge-sized units running on natural gas to provide electricity for a building that is not attached to the grid.

ECONOMIST: Fuel cells: Intel on wheels | The