Thursday, August 7, 2008
The mass media, who have a pretty good record of getting any important news wrong, have been talking up the ‘Hydrogen Economy’ quite a bit. They are mostly referring to the notion of putting powercells in cars, which split water into component hydrogen (and oxygen), then using the hydrogen as a pollution-free fuel to run vehicles.
This is a very sexy idea. It will require a gigantic investment in new infrastructure throughout the world (hydrogen manufacture, refill stations, ubiquitous fuel-cell automobiles), but this gigantic investment is small change compared to really big investments like the Iraq war. (Actually, building a hydrogen-owered world would cost slightly more than the Iraq war.)
It is also a wrong idea. It cannot ever work. This is explained nicely in an interview with Dr. Ulf Bossel, organizer of the Lucerne Fuel Cell Forum, in an interview on The Watt website dating back to 2006. Here is an illuminating excerpt:
With the same amount of electricity, original electricity, be it from wind solar energy, with the same amount of electricity you can drive an electric car three times farther than a hydrogen car. On 100 kWh of electricity you can drive an electric car 120 kilometers while a hydrogen fuel cell car of similar size can do only about 40 km. If we want to have mobility and a sustainable future, we have to go for electric cars and not for hydrogen cars because we electric cars are less costly to operate. It is not the vehicle technology, but a question of energy cost of the fuel. Hydrogen must always be much more expensive than electricity needed to split water by electrolysis etc. That is a very clear picture. I have analyzed the situation to illustrate how much water and electricity is needed for certain hydrogen jobs. If you take the Frankfurt Airport and Frankfurt Airport is perhaps comparable to the airport at Montreal. About 50 jumbo jets leave Frankfurt every day, each charged with 130 tons of kerosene. If you replace kerosene by hydrogen on a one-to-one energy base, each plane needs 50 tons of hydrogen. As a side remark: 50 tons of liquid hydrogen occupy 720 cubic meters of space, while 130 tons of kerosene take only 160 cubic meters. We need totally different airplanes for hydrogen. But that is another story. To fill the 50 jumbo jets one needs 2,500 tons of liquid hydrogen every day. 22,500 cubic meters of water, the water consumption of a city of 100,000, must be split by electrolysis. For this one the continuous electricity output of about eight nuclear power plants is needed. Now, if the entire traffic at Frankfurt Airport was all done with hydrogen, one would need the water consumption of the City of Frankfurt plus about 25 nuclear power plants. Using hydrogen for all public air and road transport in Germany, it would take the power output of about 400 nuclear power plants plus enormous amounts of water. You need nine kilograms of water to make one kilogram of hydrogen. The Rhine river and all other rivers would be dry in the summer because the water is used to make hydrogen. So, we are really approaching limits and we have to talk about these limits before we talk about a hydrogen economy.