Saturday, 15 February 2014

I say Eh-lectric, you say Eee-lectric

The big debate raging in the auto world today is whether the future will belong to what are referred to as "electric vehicles" by the lay person, or hydrogen powered fuel cell vehicles. Already there are two camps emerging - Toyota and Honda appear to have rejected the view that electric vehicles like the Tesla or Nissan Leaf will emerge as the winner, while the makers of those cars are obviously fighting back with their own version of the story yet to unfold. GM, VW, Fiat, Daimler, BMW are all somewhere in the middle - GM of course has the hybrid Volt and BMW has the all electric i3, as does VW with their hybrid Jetta - but BMW at one time also was testing hydrogen burning internal combustion engines.

What everyone seems to be overlooking is the fact that a fight between hydrogen fuel cell and electric vehicles makes no sense - simply because both are, at the end of the day, cars that move using electric motors. That's right - a hydrogen fuel cell vehicle is an electric vehicle. And what the media refers to as electric vehicles is, more accurately, a battery powered electric vehicle. The electrons that are generated by a fuel cell cannot be distinguished from those that are generated from a lithium ion battery. If you sat inside either vehicle, they would be equally silent, deliver full torque at zero speed and most likely be linked to your smartphone!

So there you have it - the debate is over - because whether we end up with fuel cell vehicles or battery electric vehicles, what they will NOT be is an internal combustion vehicle fueled by gasoline or diesel. The sooner people realize this, and the less time the auto factions spend fighting one another but trying to compete in the free market to deliver a superior product, the more likely we are to have a future where a mix of vehicles is a reality.

But before environmentalists start rejoicing at the huge emissions reduction that is going to take place when the CO2 coming out of the tailpipe is replaced by "pure" water vapor, we have to consider how these new vehicles will be fueled. Here there is a difference, albeit slight - while the battery electric vehicle will be charged using electricity, the way we charge all our other electronic gadgets, the hydrogen fuel cell vehicle will need to refilled with hydrogen at a location similar to a gas station. So the battery electric vehicle merely stores electricity and releases it, a fuel cell vehicle involves a chemical reaction that results in the generation of electrons.

Both a lithium ion battery (or for that matter, any battery) and a fuel cell are incredibly complex systems of materials that are designed to either store or generate energy. They have to compete with a fossil fuel like gasoline that has an enormous energy density and, as a liquid, can be transported long distances easily, thus resulting in a global infrastructure that has been built up over a hundred years.While R&D at both the private and government level is on-going, it will be several years or decades before either of these can compete with an internal combustion engine for power, reliability and cost.

Getting back to the fuel that will drive both battery and hydrogen vehicles - as the economy moves towards cleaner sources of energy, natural gas will be the preferred fuel for electricity generation. So a natural gas fired power plant will send the electricity over to your house or to a public charging station where you charge your battery driven car. But what about the hydrogen? Where does that come from?

Almost every report on hydrogen cars will reinforce the cliche that it is the "most abundant element in the universe". And while that is true, all of the free hydrogen that can be theoretically used to power fuel cells exists in outer space. On earth, hydrogen is bound with other elements, most notably oxygen to give the molecule without which life could not exist - water. So if we wanted to extract hydrogen to power fuel cells, you would need to take water and split it apart, which is highly energy intensive.

Luckily for us, another abundant hydrogen containing molecule that can be used is - natural gas. A very well established reaction called steam methane reforming is used to generate hydrogen which can then be used for fuelling cars. And since natural gas pipelines exist in many locations (and infrastructure next only to oil pipelines), the hydrogen would presumably be generated at specific locations, much like a transformer steps down the high voltage in transmission lines to the 110/220v for domestic use, and then used for filling cars.

But wait - isn't natural gas also being converted to electricity that is used to charge a battery electric vehicle? Yes it is! So there you go - another reason that the "hydrogen vs electric" debate is less competition and more cooperation - because they share the same start fuel, one that has the ability to drastically reduce carbon emissions and realize all kinds of global targets for climate change. The time is ripe for a natural gas producer/distributor to take the leap and start the transition to a gas driven economy.

And what about when the natural gas runs out one day, as it surely will? Well, in that case, the hydrogen in outer space will surely come in handy - sunlight, which is the direct product of hydrogen fusion to helium, will create electricity from solar panels which will then charge our cars. So in the reeeeallly long run, battery electric vehicles will win out - but by then, who knows what the world will be like?





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