October 12, 2011
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If petroleum-based fuels are not the future for the transportation industry, what will take their place? Today, biofuels play a significant role, moving a portion of the nation’s energy supply away from traditional gasoline and diesel. But, concerns surrounding the amount of farmland used to produce these biofuels rise, it becomes increasingly unlikely that biofuels will be able to eliminate our reliance on petroleum-based fuels. Some support hydrogen as a source of energy for the transportation sector. But, as Sheril Kirshenbaum explains, when it comes to hydrogen, “we’re not there yet.”
One of the perks of being a Hill staffer is access to cool new technologies when lobbyists visit. And so in 2006, I looped around D and 2nd in a hydrogen car. When I asked the nice man who brought the vehicle about safety and the inherent ‘chicken and egg’ problem (cars and fueling stations – which comes first?), he provided a clearly scripted response intended to brush off public concerns. I was sure he’d repeated it dozens of times that afternoon and–needless to say–I wasn’t convinced.
You see, despite all the hype, hydrogen is unlikely to become a significant source of energy. I’ll explain what makes this energy carrier appealing, followed by outlining its detractors, especially regarding use in personal vehicles.
Hydrogen has superior energy density compared other fuels (a whopping 120 MJ/ kg in the liquid form). You may remember that George W. Bush often brought up the way its combustion yields water avoiding emissions. He committed over $1 billion to the development of a hydrogen car. And it’s true that fuel cells can produce electricity with high efficiency and no moving parts. They are quiet and can also be designed at different scales depending on intended use. So far, so good.
BUT hydrogen is not available in enormous reservoirs in the Earth’s crust and requires energy for production. Although current high cost and unreliability should become less prohibitive as technology improves, the distribution issues that would be required for use in personal cars are more difficult to overcome. On top of that, liquid hydrogen must be maintained below -241 C so storage poses problems. Finally, there’s the enormous elephant in the room: Safety. Hydrogen is highly flammable with an ignition energy 1/10 of gasoline.
So yes, the prospect of using hydrogen has some appeal. It’s most plausible in fleet vehicles like buses which would require fewer filling stations. However, it’s unlikely we’ll all be whizzing around in our own personal hydrogen cars anytime soon.
About the Author:
Sheril Kirshenbaum is a science writer and research associate at the Center for International Energy and Environmental Policy at the University of Texas at Austin. She is the author of two books – “Unscientific America: How Science Illiteracy Threatens our Future” and “The Science of Kissing.” Sheril currently blogs at Culture of Science.
Photo Credit:
1. Photo of gas tank door on hydrogen vehicle © by Zero Emission Resource Organisation and used under this Creative Commons License.
[A version of this post was previously published on June 6, 2010]
About the Author: An engineer and researcher who works at the intersection of energy, environment, technology, and policy. Follow on Twitter @mclott.
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What this really describes is the problem with our government. All these staffers got a fun time in some cool technology from a lobbyist. Now they owe this “nice” guy. Next, when he comes by asking for money for some plausible-sounding boondoggle they are going to have a hard time saying no. Rationalization is easy. It’s only a few hundred million (of taxpayer money, not their money), a drop in the bucket. It will boost the economy… Of course they claim that THEY will not be influenced. All those psychological studies on influence and reciprocation don’t apply to THEM.
One of the things we need to do is cut off the access of these lobbyists and get the decision makers back into their districts so they spend time with the people they are supposed to be working for instead of the ones who can afford to send people like this into Washington to get what they want out of the government.
Link to this@cogitari: It’s simplistic to think that lobbyists are always bad or that it would be good if our policymakers received no input from lobbyists. Lobbyists are neither intrinsically good nor intrinsically bad. They provide input from constituencies. This input is no more or less intrinsically valuable than input from ordinary voters, who are often (usually?) uninformed, especially about technical issues. It is the responsibility of policymakers to weigh input from all relevant sources. It would not be beneficial to insulate them from input from constituencies represented by lobbyists even if that were possible, which it is not.
Link to thisWhat Sheril Kirshenbaum and many fail to consider is that a hydrogen distribution system is not necessarily needed for transportation vehicles especially in the early stages of development. Hydrogen can be easily extracted from water and a home based or regional based converter could be made available. The hobbyist model rocket builder Estes use to make a rocket that used hydrogen fuel made from water using the electricity from “D” cell batteries.
http://www.amazon.com/Estes-Hydrogen-Fuel-Rocket/dp/B0000AOVTZ
There is no reason why units could not be scaled up to power cars and larger vehicles. True, this would probably not be a scalable concept but a business would be much more likely to invest in a hydrogen distribution system if there was a ready made market of home owners, businesses and municipalities that were already operating vehicles with hydrogen produced from their own units. If someone could distribute hydrogen for less than people could make it themselves they would have a viable business. And there would be a built in mechanism too keep prices down. If prices got too high people could go back to making their own.
Just an idea.
Link to thisYouTube is full of videos where someone hooks up their car battery to a jug of water, then pipes the resulting mixed H2 and O2 electrolysis products straight into the gasoline engine. It’s enough to keep a gasoline engine idling, but no more. Sure, it’s not “practical”, but these guys (and BMW with their H2 burning V12 and Honda’s FCX H2 fuel cell electric) are demonstrating that we are not that far from mass produced H2-burning or even H2-fuel-cell-electric cars.
Europe is building an H2 highway corridor now.
http://www.hydrogencarsnow.com/eu-hydrogen-highway.htm
Safety? How many car fires are caused by the fuel are there now? Too many! How many gasoline station fires are there now? Too many! Still we don’t expect to see car fires and gasoline stations burning every day. We will never completely eliminate risk, but H2 storage, distribution, and use can’t pollute the environment the way leaky fuel tanks or burning petroleum have already.
The implication that we can only use cryogenic storage for H2 is ridiculous. High pressure storage is a more likely solution. There are metal-adsorption schemes that lock up H2 on the surface of metal plates, and then use heat to liberate the H2 when needed.
This article is entirely superficial and doesn’t really illuminate any of the issues around H2 fueled transportation.
Link to thisA comment from Google+ to add to this discussion:
Link to thisFrom C.H. – The state of development of FCVs today indicates that they are not near commercialization, to be sure, but I’m not convinced that hydrogen should be abandoned as a possible vehicle fuel as some in the administration do. We’ve yet to find an alternative that has an energy density on a mass and volume basis comparable to hydrocarbon fuels, but if we’re to be honest with ourselves, we should compare the performance (and theoretical limits) between alternatives, not against the incumbent, especially if we’re going to “pick winners” through big investments in R&D.
To some of the specific points raised by Sheril – if we’re going to pursue NGVs (natural gas), FCVs or EVs, the infrastructure issue is similar (though clearly the worst for hydrogen), so infrastructure arguments are, in my mind, a little thin. Further, when we look at the two options I believe we’ve invested the most R&D money into thus far, EVs and FCVs, the staggering weight of batteries means they will likely never be viable (except perhaps if we make dramatic progress on reversible Li-air chemistries) for any heavy-lift or air-based transport applications.
Given the long-term benefits of a move to transport fuels that rely on electricity (that can be generated sustainably and/or with lower emissions), I don’t think we should be too hasty to give up on any reasonably viable “fuel” option. That’s why we should divert all our nuclear fusion research funds to hydrogen for transportation instead…obviously.
A comment from Google+ to add to this discussion:
Link to thisFrom C.B. – This seems relevant:
http://energy.sandia.gov/?page_id=776
I think that liquid hydrocarbon fuels will be around for a long time because they’re so practical. However, I think that we’ll learn to synthesize them without petroleum.
Also, we need to be doing exergy analysis on energy systems. This is a good example of how to do things right:
http://www.amazon.com/Nonlinear-Power-Flow-Control-Design/dp/product-description/0857298224
The science of thermodynamics is able to show that chicken came first than egg. Liquid Hydrogen as an energy storage mean is probably not feasible today and in the near future. Or it is ?
Link to this