There has been a lot of hype about Hydrogen, especially about the new Hydrogen concept cars with integrated fuel cells and the hydrogen economy that will supposedly fuel these cars. Now at first, after watching some of these shows on television, I too was hypnotized by the “Hydrogen as a clean alternative fuel” idea that seems to be so prevalent in the auto industry. However after digesting everything I had learned about hydrogen, energy and economics, a few things began to stand out and some of the logistics were just not working out.
After arguing with a few friends of mine about Hydrogen vs. electricity as a fuel source, it seemed to me that most people believe that the energy output from using hydrogen fuel cells is more than the energy input. Now I’m no physicist, but I did take a few Physics classes in college and this idea seems to be breaking a fundamental law of physics; the Law of Conservation of Energy. In short, the law of conservation of energy states that energy can not be created or destroyed; it can only be changed from one form to another, such as when friction generated from kinetic energy changes into thermal energy (heat).
From this law of physics we can conclude that the energy used to split Oxygen and Hydrogen in water will equal the energy received when the Hydrogen and Oxygen are reunited to form water in a fuel cell, minus any energy loss in the form of heat. This led me to research the fundamental properties and efficiencies of hydrogen electrolyzers. This led me to the Hydrogen Association website where they mentioned that there is a 20% to 30% energy loss when you go from electricity to hydrogen and then back to electricity. This doesn’t even take into consideration all of the energy loss further down the line such as the pressurization of hydrogen into liquid and the transportation of the hydrogen to fueling stations across the country. If all of these efficiency losses are taken into consideration, you are looking at a 75% efficiency loss before the hydrogen even gets put into the vehicle.
Now this doesn’t mean that I think Hydrogen fuel cells and hydrogen fuel are bad ideas, on the contrary, I still love the idea of hydrogen as a fuel source, but as it stands now, this “Hydrogen Economy” everyone is talking about will be much worse for the environment than continuing to use gasoline. This is because the way Hydrogen is currently produced is from steam reforming natural gas which is not the most cost effective or environmentally sound technique. The only way that Hydrogen will make sense economically and environmentally is if all Hydrogen refueling stations would use some form of alternative energy to produce the Hydrogen on-site. Norway is a prime example of proper Hydrogen infrastructure with their “Hydrogen highway” peppered with independent solar powered hydrogen fuel stations.
With all of this being said, no matter how you look at it, electric vehicles are more efficient than hydrogen vehicles, simply because you eliminate a process in which efficiency is reduced. Personally I would like to see more research towards electric vehicles and battery system than hydrogen vehicles because they are that much more efficient and better for the environment. Another common misconception is that an electric vehicle using electricity from a dirty electricity plant is worse for the environment than a gasoline vehicle. Although I do not recommend using dirty electricity to recharge an electric car, the fact is, even if an electric vehicle gets all of its energy from a coal burring electrical plant, the net environmental impact for that vehicle will still be far less than an average gas powered vehicle.
The most common argument against electric vehicles is the range. Now in this respect I have to agree that many of the electronic vehicles that I have seen to have pretty short ranges. Recently however, I have seen a few electric vehicles that can go about 200 miles on one charge and be recharged in as little as 10 minutes (from high powered recharge stations). Some people will say that 10 minutes is too long to wait for a refill, but I must disagree. The fact is, the average person can use a typical 110V outlet at their home and recharge their electric vehicle (EV) overnight. This essentially eliminates the need to ever go to a recharge station. In the rare event that someone is driving across country (over 200 miles) then why not just take a 10-15 minute break every 200 miles to recharge, get some coffee or food and relax.
Overall electric vehicles are far superior in many regards to their hydrogen counterparts and as the technology gets better I believe that we will see even further ranges and faster recharge speeds. With the integration of solar panels on the roofs of electric vehicles, those sunny days will no longer just make your car incredibly hot, but you can be recharging your batteries while it is parked at work. Batteries are also getting much more efficient and new discoveries are happening every day which will revolutionize the battery industry. With better batteries and more efficient vehicles, the idea of a sustainable automotive industry is quite possible.