A hydrogen fuel cell car seems to be a step in the right direction in the battle against greenhouse gases. What sounds most appealing is that there is no by-product of CO2 when a hydrogen fuel cell creates energy. The cell releases mainly H2O.
However-
1. Actually producing the hydrogen CAN be a source of CO2 emissions. First of all, hydrogen is an “energy carrier.” It’s produced from other energy sources. Hydrogen is not found in nature by itself, and processes such as electrolysis or to separate the hydrogen do release CO2 into the air. SMR (steam methane reformation) uses high temperatures and pressure to break hydrocarbon into hydrogen and carbon oxides which are then emitted as greenhouse gases.
2. Transportation of hydrogen poses another problem. Hydrogen isn’t as compatible as oil or gas for our pipelines. Creating new methods of transportation means more costs and more fuel used for the production.
3. As mentioned in the class blog, the United States does not the overall infrastructure to support these hydrogen fuel cars. Switching companies over would be a huge project, demanding lots of energy and expenses. (It may cause many to lose their jobs). Besides, not all companies can be expected to make the change. Do we have the resources to support hydrogen and gasoline systems?
4. Production of the actual cars requires separate own costs and energy/fuel demands.
5. A fuel cell’s performance, similar to a battery’s, decreases over time and needs to be replaced. Continually producing the materials for the vehicle which eventually leads to more greenhouse gases in the atmosphere.
6. Processes to obtain hydrogen are not completely efficient. So, more energy is necessary to create the hydrogen than what we’re getting out of it. Again, the efficiency is not 100% when the fuel cell powers the car motor. The buildup of inefficiencies and their effect on our resources has a chain effect to CO2 emissions.
7. Aside from CO2, hydrogen fuel cells release H2O which is a main greenhouse gas. The amount is not hugely significant, but it is a lot higher than the water produced from burning gasoline.
Sources:
http://fuelcellsworks.com/JustthebasicsonHydrogen.html
http://news.bbc.co.uk/1/hi/sci/tech/2840191.stm
http://whyfiles.org/shorties/174fuel_cell/
http://www.popularmechanics.com/technology/industry/4199381.html
Increasing water concentrations in the atmosphere is not a concern because of rain and snow. In other words, there is a maximum level of water in the atmosphere and when it is reached, it rains. That’s an efficient way of removing this greenhouse gas.
Sinks for CO2 and other greenhouse gases are not so efficient.
Comment by mrmc — February 7, 2008 @ 5:44 pm
Somehow i missed the point. Probably lost in translation
Anyway … nice blog to visit.
cheers, Wordlessly!!!
Comment by Wordlessly — June 19, 2008 @ 1:04 pm