Natural gas and hydrogen are both gaseous fuels. Natural gas has the highest hydrogen-to-carbon ratio of any energy source as it is made up of four hydrogen atoms and one carbon atom (CH4). Hydrogen is considered to be an energy carrier rather than an energy source. Hydrogen can be produced from natural gas or from renewable energy sources such as water.
Natural gas can be blended with hydrogen to reduce smog-related emissions from vehicles. Vancouver’s regional transit authority, TransLink, is one of several North American transit operations that have demonstrated the use of natural gas-hydrogen fuel blends in transit buses. Typically, the fuel consists of 20% hydrogen and 80% natural gas. Specialized materials are needed for fuel blends with a concentration of more than 20% hydrogen.
Lessons learned from natural gas vehicles and stations can help develop hydrogen as a transportation fuel. For example, the vehicle systems used for pressure regulation and delivery of a gaseous fuel to an internal combustion natural gas engine have been successfully applied to hydrogen internal combustion engines.
Bus garages and vehicle storage facilities that are built to handle lighter-than-air fuels can be safely used for natural gas or hydrogen vehicles. Designing facilities that can be used to handle gaseous or liquid fuels is a cost-effective way to plan for alternative fuel use.