The 21st century gave birth to a race all humankind takes part to. Like it or not, the reign of fossil fuel is about to end with a large bang. Engineers, scientists and pioneers of technology developed viable alternatives with two goals in mind:
- Provide a virtually non-depletable source of energy
- Make sure said-energy is clean, or at least cleaner than fossil fuel
Still, what’s wrong with fossil fuel, as long as there’s still some left? In short words, greenhouse emissions. On a worldwide scale, humanity is getting around 80% of the energy it requires by burning fuel, according to World Bank stats. While the percentage may have dropped since the 60s, the quantity of fuel burnt increased dramatically, thus raising the level of greenhouse emissions. Carbon Dioxide (CO2) is the main element of the heat blocking blanket our Earth has been covered with and vehicles produce tons of it every single day. A study done by EPA shows 6,780 metric tons of CO2 have been released in the air in 2014.
How does hydrogen come into play?
Unlike conventional heat engines, eco-friendly machines can electrochemically transform hydrogen in usable electric energy. The energy resulted is used to power electric motors, for example in consumer vehicles.
The entire process is possible thanks to one or more fuel cells. A fuel cell uses a polymer electrolyte membrane (PEM) to harness electric power. The system is composed of a cathode and an anode sunk in an electrolyte, all covered on both ends by energy harnessing bipolar plates. In the anode, the hydrogen is separated into protons and electrons, while a membrane allows only protons to move further. In the meantime, electrons travel on a separate route towards the cathode, creating electricity through their movement. Once they return from the trip, hydrogen electrons react with oxygen and hydrogen protons, generating heat that can be further used by other systems.
Hydrogen cell efficiency in transportation
For the moment, hydrogen cells are not being used on a full scale in the automotive industry. The first ever commercial vehicle to run solely on hydrogen is the 2015 Toyota Mirai. It runs solely using hydrogen cells and exhausts drinkable water.
Of course, all hydrogen based cars use electric motors to generate thrust. There are various advantages of an electric engine compared to a standard fossil fuel unit:
- Higher efficiency (60% electric vs 35% gasoline/diesel)
- Instant torque over a wide RPM range
- Removes the need for a geared transmission
- Low maintenance costs (fewer elements requiring replacement)
- Less noise
Hybridization – path to cleaner air and cheaper transportation?
It is pretty obvious that hydrogen fuel cell vehicles are better from almost any point when compared to traditional fossil fuel cars. They indeed allow for a cleaner air especially within cities where the exhaust fog is a serious issue in the last decade. Exhausting just water is a main plus when working in this direction.
It also needs to be mentioned that current fuel cell vehicles can achieve ranges of around 400 miles before needing to be recharged. And, compared to electric vehicles that rely on batteries to work, filling a tank of hydrogen takes just as much as it takes to fill one with gasoline. However, Tesla CEO Elon Musk considers hydrogen cars as being silly. What could be the reason?
First of all, it is true that creating electricity from hydrogen takes a lot more in account than simply delivering it to a set of batteries. With hydrogen, atoms must be separated in protons and electrons, then reunited and then finally exhaust the resulting water. Even more, it is a known fact that fuel cells heat up more than you’d want to. It’s a prime reason why Toyota Mirai is using large air intakes on the front fascia, to dissipate the heat.
Furthermore, when compared to fully electric vehicles, hydrogen cars aren’t all that cheap in terms of fuel. It costs around $40 to fill a tank with hydrogen, lasting for around 350 miles, in case of Honda Clarity. On the other hand, according to Tesla’s calculator, it costs just around $16 to charge your vehicle for 400 miles. Of course, it will take 90 minutes to do that.
Conclusion – Do Hybrid Vehicles present a Viable Future?
Someone has to admit it: Elon Musk’s statement on hydrogen vehicles only last as long as the current hydrogen infrastructure and technology does not advance. However, given the amount of research and development done in the field, hydrogen vehicles may very well become a popular choice along consumers, ensuring breathable air and lower costs.