What Will Be the Fuel for Future Vehicles?

Recall childhood imaginations of a car that can fly, float on water, or dive underwater. Have we come close to these imaginations? While vehicles capable of flying or moving on water have been developed, it is unlikely that such vehicles will become commonplace in the next fifty years due to more pressing issues. Currently, the biggest issue is fuel. Greenhouse gas emissions are increasing daily, and the Earth is warming, so instead of focusing on flying cars or floating vehicles, automakers should address this problem. Electric vehicles are one solution, but there are significant challenges in their development, primarily high costs and limited range. Currently, Tesla has been successful and is a leader in electric vehicle production. The Tesla Model S can travel 370 kilometers on a single charge, but charging the battery with the most advanced technology typically takes over an hour. This model costs $65,000. The issues of limited range, storage, charging, and high prices have made electric vehicles less attractive options, which is why hydrogen vehicles are more prominent for the future. Hydrogen is one of the most abundant elements in nature, and burning hydrogen produces only water; theoretically, everything seems perfect, but in practice, there are still many problems. The most significant discussions revolve around hydrogen production and storage. The most common methods for obtaining hydrogen involve extracting it from water or fossil fuels like natural gas. However, the challenge lies in hydrogen storage. Hydrogen boils at negative 252 degrees Celsius at sea level pressure, making liquefying hydrogen very complex and costly; compression also requires very sophisticated technology. One practical method is storing hydrogen using hydrides, which offers great hope for future vehicle use. But let's assume the storage issue is resolved; how can hydrogen be used in vehicles? One way is to use hydrogen in internal combustion engines instead of gasoline or diesel. BMW has conducted research on this with a prototype vehicle. In 2007, this German company introduced the BMW H7, which, similar to the gasoline-powered 7 Series, used a 12-cylinder 6-liter engine. This model consumed 14 liters of gasoline per 100 kilometers, while for hydrogen, this number reached 50 liters per 100 kilometers! But why? The energy produced by each liter of gasoline is 34 megajoules, while for hydrogen, it is 10 megajoules. This BMW research vehicle shows that the efficiency of a hydrogen vehicle with an internal combustion engine is very low, which is why many companies, including Toyota, are pursuing another method called fuel cells. Toyota has recently launched the world's first commercial fuel cell vehicle. This vehicle can travel 502 kilometers on a full hydrogen tank. Its electric motor has a power of 152 horsepower. In this vehicle, hydrogen stored in tanks at 70 megapascals (700 times atmospheric pressure) moves to the fuel cell unit, where it mixes with oxygen from the air, resulting in the production of water and electricity. The electricity is used by the electric motor to move the vehicle, and water is expelled from the vehicle's exhaust. If you hold a cup in front of the exhaust while the vehicle is idling and you press the gas pedal, the cup will fill with water after a while. This vehicle currently costs $75,000. Jackie Birdsall, an engineer in Toyota's fuel cell vehicle department, explains to Al Jazeera English that this vehicle has passed various safety tests, including fire tests, and there will be no issues with the high-pressure hydrogen tanks installed under the vehicle. The bottom of the vehicle is fully covered to protect sensitive components like the fuel cell and hydrogen tank. But what distinguishes fuel cell vehicles from electric vehicles, leading to a greater inclination towards fuel cells for future vehicles? Both methods ultimately power the vehicle with an electric motor. The important point is the faster refueling or charging time for fuel cell vehicles. With current technology, these vehicles can be refueled in 5 minutes, while this time is significantly longer for electric vehicles. Another very important point is that fuel cell vehicles are cleaner. The electricity supplied to electric vehicles may come from fossil fuel sources, ultimately causing greenhouse gas emissions similar to current vehicles, while the electricity for fuel cell vehicles is generated from the reaction of hydrogen and oxygen. Although Toyota is currently the leader in commercializing fuel cell vehicles worldwide, General Motors with the Chevrolet Equinox Fuel Cell, Honda with the FCX Clarity, Hyundai with the ix35 FCEV, and Mercedes-Benz with the B-Class F-Cell are following closely behind.