To start with, Hydrogen will be blended with CNG to reduce Nitrogen Oxide and Particulate Matter emission from vehicles by almost half. "Hydrogen is the cleanest among all available fuels including bio-fuels. It's burning emits no carbon and the final result is water," said Dr SK Chopra, Special Secretary in the Ministry of Non-Conventional Energy.

For CNG blended with Hydrogen till 10 per cent, only a few improvements in vehicle with no engine modification is required. If the blending is more than 10 per cent, engines modifications are mandatory. Seven vehicles models --- Tata Indica, Tata bus, Bajaj three wheeler, Ashok Leyland mini bus, Eicher mini bus, Mahindra three wheeler and Mahindra Utility --- are expected to be ready by early next year with modifications to run on up to 30 per cent Hydrogen blend. 

Duleep Chenoy, Director-General of Society of Indian Automobile Manufacturers (SIAM), said, "Engine optimisation of these seven types of in-use CNG engines have already begun. By early next year these vehicles will be ready for field trials". Before SIAM, Banaras Hindu University has developed modified two-wheeler and three-wheeler engines compatible for CNG-Hydrogen mix and rights have been bought by Hosiarpur based International Cars and Motors Limited to manufacturer three wheelers. 
 
With the already successful CNG model and tests on in-use CNG vehicles being carried out in the Capital, Chopra said, the government opted for the city with an "eye on huge potential for an alternative fuel." In addition, the new blended fuel is expected to reduce Nitrogen Oxide (NOX) and Particular Matter (PM) emission by almost half -- a boom for the city grappling with high levels of NOX and PM. 

Despite the advantages, the competition between Hydrogen and CNG would be stiff. Hydrogen as a fuel is four times as costly as CNG, even though it has three times more energy than CNG. "The initial manufacturing cost of Hydrogen is high because of the cost of technology involved. We are confident that the prices will fall once the market for Hydrogen gathers momentum," Malhotra explained.  
 
The first filling station, having Hydrogen manufacturing and storing facility, will cost about Rs five crore, to be equally shared by IOC and the ministry. The station will have generation capacity to meet demand of over 1,000 vehicles in a day. Officials said the vehicles manufacturers would also come up with facilities to modify existing CNG vehicles for the Hydrogen blend.