A test run of India’s first bus powered by liquid hydrogen was recently completed in the south Indian city of Tirunelveli, Times of India reported on Monday.

The 5km test run was partly overseen by Tata Motors Limited (BOM:500570), which spent five years researching and building the vehicle.

Compressed liquid hydrogen is stored in cylinders on the bus roof and converted into electricity by hydrogen fuel cells.

“This is basically an electric operation using hydrogen fuel. As the by-product is water, absolutely there is no emission at all,” said researcher V Gnana Gandhi to the Times of India.

Testing the vehicle for stretches of 1,000 to 2,000 kilometers is the next step, likely via several daily runs of 100km to 200km. Tata Motors will continue to work to make the bus more roadworthy, said Gandhi.

The safety and logistics of using hydrogen fuel are key issues involved in the vehicle's development, Gandhi said.