Introduction
It is an article about Hydrogen fuel is a zero-carbon fuel burned with oxygen. As hydrogen fuel cell vehicles switch from the demonstration to commercialization, the users expect safe, comfortable, and customer-friendly fueling. It can be used in fuel cells or internal combustion engines. It has begun to be used in commercial fuel cell vehicles, such as passenger cars, and has been used in gasoline cell buses for many years. It is also used as a fuel for spacecraft propulsion

Hydrogen fuel
Hydrogen quality affects fuel cell stack performance and service life, and other considerations such as valve operation. In this paper, previous researcher’s development on hydrogen as a possible main fuel of the future has been studied thoroughly. Hydrogen is one of the energy carriers which can replace fossil fuel and can be used as fuel in an internal combustion engine and as a fuel cell in vehicles.

To use hydrogen as a fuel of internal combustion engine, engine design should be considered to avoid abnormal combustion. As a result, it can improve engine efficiency, power output, and decrease the NOx emissions. The emission of fuel cell is low as compared to conventional vehicles but as penalty, fuel cell vehicles need additional space and weight to install the battery and storage tank, thus increases it production cost. The production of hydrogen can be ‘carbon free’ only if it will be generated by employing genuinely carbon-free renewable energy sources. The acceptability of hydrogen technology is dependent on the knowledge and awareness of the hydrogen are the advantages towards environment and human life. Recent study shows that people still do not have the sufficient information of hydrogen. Hydrogen fuel cells are relatively expensive to produce, as their designs require rare substances the new technology uses durable nanowires instead of the nanoparticles. “The next step for the researchers is to scale up their results so that the technology can be implemented in hydrogen vehicles.”

THE HYDROGEN CHALLENGE:
Fuel cell Source This device converts hydrogen to electric power. The challenge is to make it light, cheap, robust, and
durable — yet powerful enough to run the engine, lights, and air conditioning. The future of hydrogen fuel-cell vehicles depends on advances in four key areas: the hydrogen source, the distribution infrastructure, the on-board fuel tank, and the on-board fuel cell.

Fuel tank:
Fuel-cell vehicles must store enough hydrogen to go several hundred kilometers between refueling stops. Liquid hydrogen requires insulated tanks at −253 °C. So, most companies have chosen to compress the hydrogen inside high strength carbon-fiber tanks. Source Hydrogen must be derived from carbon-free renewable sources before fuel-cell vehicles can make a dent in the climate problem. One idea is to make the hydrogen by splitting water using electricity from wind farms, solar panels, or nuclear plants.
Fuel cell:
Source This device converts hydrogen to electric power. The challenge is to make it light, cheap, robust, and durable — yet powerful enough to run the engine, lights, and air conditioning.
Future
A seamless transition from a petroleum-driven transportation system to clean-burning automobiles with the efficiency and range of today’s gasoline cars is plausible using high efficiency hydrogen-fueled hybrid electric vehicles. The introduction of hydrogen vehicles will reduce U.S. Dependence on oil imports, virtually eliminate automotive urban air pollution, accelerate the development of cost-effective energy from renewable sources, and help stabilize greenhouse gas emissions.

Based on an economic and technical analysis, H2 vehicles, when presented for the first time, can be cost-competitive with battery-powered electric vehicles. As market penetration increases, H2-vehicle fueling costs would
become competitive with the fueling costs of today’s gasoline vehicles. Hydrogen production at filling stations, vehicle fleets, and homes would circumvent many start-up issues and would use existing natural gas and/or electricity energy infrastructures to begin the transition towards a clean, flexible, sustainable, and secure transportation fuel.
Disadvantages:
Expensive to manufacture due the high cost of catalysts (platinum), Lack of infrastructure to support the distribution of hydrogen, A lot of the currently available fuel cell technology is in the prototype stage and not yet validated and Hydrogen is expensive to produce and not widely available.