What is a Hydrogen Car?
Hydrogen Fuel Cell is an alternative method of storing energy in the form of hydrogen molecules, the highly pressurized hydrogen mixes with oxygen performing an electrochemical reaction which produces electricity to power the electric motor. The Hydrogen Car can be characterized of both electric cars and conventional cars, where it has a tank to store the Hydrogen as conventional cars and the way of producing the power as in electric cars.
Using the hydrogen is a smart idea to power the cars since it is one of the most common elements in our planet, but it is rarely found in a pure form, usually it can be found in combination with some other materials such as in Water (H2O) or in the Natural Gas (CH4). The specific energy for the hydrogen is about 40,000 Wh/kg comparing to the Lithium-Ion battery of just 278 Wh/kg since it has less density. Moreover, the time it takes to charge the car takes about 5 minutes where electric cars need around 30 minutes for a full tank charge.
Why haven’t we start using it?
Hydrogen seems to be a clear winner in this comparison, but the true challenge is laying behind the scenes. First the cost/km for the hydrogen fuel is 17.7 cents compared to electricity with only 2 cents, and that is because the hydrogen requires more energy to produce.
Since hydrogen is not available in a readily form, the process of extracting the hydrogen from the water requires a high amount of energy. The most efficient technology to extract hydrogen is the Proton Exchange Membrane (PEM) and the electrolysis. Experts say by 2030 the PEM will reach an efficiency of 86% but it is still not comparable to the battery’s efficiency where it reaches 99%, and that’s only the efficiency of producing the electricity, not to mention the charger, compression, fuel cell and transportation inefficiencies. All in all, combining all the inefficiencies from the very first beginning to the end use, the hydrogen car in best case scenario has a total efficiency of around 25% where the electric cars around 75% even when they have a renewable source of energy as an input.
So, while the hydrogen car seems to travel farther distance with a one tank over a battery powered car, the cost of that fuel is extremely higher due to all the losses and the inefficiencies. Unless we can find a way to increase the efficiency and reducing the cost of hydrogen production, the electric vehicle still a better option for both the climate and the customer. Better technologies may develop to increase the efficiency and reduce the cost in the future such as PEM, or maybe other approaches could be studied for a better performance, could it be hybrid car of both electric and hydrogen?