|What follows is not meant to bash EVs, plug-ins or biofuels. And yes, hydrogen faces substantial challenges, chief among them vehicle cost and fueling infrastructure. But we need to be honest about all the options, or risk falling down the rabbit hole with Alice.|
|Hydrogen - Because we need it!|
By Robert Rose, Fuelcells.org
Folks, it’s time to stop bashing hydrogen, not because we love it but because we need it. Practically speaking, we simply cannot achieve the goals of energy security and climate stability without a transition to hydrogen and fuel cells.
I think most of us can agree that we need to move away from fossil fuel consumption for transportation energy to achieve energy security, clean up smog and reduce human-generated climate change emissions. I think most of us can agree that the car of the future will be an electric-drive car. The questions center on what will drive the wheels of the EV and on what part combustion will play.
Dedicated EV’s, plug-ins, and biofuels will all need to do their part, but they won’t get us across the goal line without hydrogen. The good news is that with successful interim steps, by moving to hydrogen we can virtually eliminate demand for motor gasoline, and cut CO2 emissions by 80 percent. http://www.nap.edu/catalog.php?record_id=12222.
What follows is not meant to bash EVs, plug-ins or biofuels. And yes, hydrogen faces substantial challenges, chief among them vehicle cost and fueling infrastructure. But we need to be honest about all the options, or risk falling down the rabbit hole with Alice.
Hydrogen advocates argue that fuel cells and hydrogen will provide the greatest overall benefits, and indeed are essential to achieving our social goals while preserving consumer choice. (Dr. Sandy Thomas did a study entitled “Comparison of Transportation Options in a Carbon-Constrained World: Hydrogen, Plug-in Hybrids and Biofuels” http://www.fuelcells.org/info/thomasstudy.pdf) Those who disagree tend to argue that a combination of plug-in hybrids and advanced “Gen 2” biofuels will be sufficient.
But the biofuels pathway is very challenging and expensive, and preserves a system that relies on fuel combustion, with all its pollution and efficiency consequences. The estimated cost of providing sufficient biofuels (see below) suggests to me that the hydrogen pathway may actually be cheaper and will yield greater benefits.
Plug-ins are still in development; -- as someone pointed out, there are more OEM fuel cell vehicles on the road than OEM plug-ins -- and we still have much to learn. Costs are high, the batteries must be imported. (Even GM will assemble packs using Korean cells.)
Mileage depends on the duty cycle; the vehicles are “flex fuel” and not everyone will plug in every day. To avoid burdening the grid with new demand at peak afternoon times (right after work, for most people), vehicles or infrastructure will need to be designed to allow charging only at non-peak times; this could affect consumer satisfaction and/or the choice of whether or not to plug in.
CO2 and air pollution benefits depend on the electricity generation mix and the duty cycle, since the combustion engine will still be producing those nasty smog precursors as well as CO2. There are questions about how marketable plug-ins will be given their cost, uncertain resale value and small size.
As for dedicated EV’s they are a niche technology at present – a great niche, but a niche. While high-tech marvels like the two-seat Tesla can claim about 200 miles per charge, a more realistic estimate for a family sedan is 100 miles or so. It ought to be enough for a lot of drivers but experience has proved dedicated EV’s are tough to sell.
Even if we assume that these pathways are so successful they shift two-thirds of vehicle energy demand to the electric grid, that still leaves one third that must come from gasoline or something else. That “something else” is usually identified as advanced biofuels. A revealing new analysis by Sandia National Laboratory concludes it may be possible to generate that much, but only if we overcome daunting technical and cost challenges. http://hitectransportation.org/news/
Given all these technical, cost and marketplace uncertainties, I am led to the conclusion that the prudent approach is to keep the door open for another pathway, hydrogen and fuel cells.
Among other things, it will take 90 billion gallons of biofuel annually to achieve 33% petroleum displacement in 2030. Just producing 60 billion gallons by 2030 was estimated to cost $250 billion. Achieving that level of production would also require substantial improvements in technology, to achieve an average of 95 gallons of fuel per dry ton of feedstock -- more than the theoretical yield of some feedstocks, such as forest cuttings. http://www1.eere.energy.gov/biomass/ethanol_yield_calculator.html
Sandia estimates that this pathway would reduce CO2 emissions by 250 million tons – assuming no impact from land use changes (a highly questionable assumption). That’s a little more than 10 percent of current transportation sector emissions – at best.
Fuel cells and hydrogen face substantial challenges just as do the alternatives. But fuel cell vehicles have made dramatic technical progress in the past three years, and those who last looked seriously at fuel cells and hydrogen in 2006 should look again. The combination of benefits includes high efficiency and therefore low CO2 emissions even using hydrocarbon fuels, no combustion aboard the vehicle and therefore no smog causing emissions, performance and consumer satisfaction, scalability to allow production of a full range of vehicles, and portability of the fuel. It is this combination that I believe makes the crucial difference.
The best vehicles have achieved more than 400 mile range; the new Honda is comparable or superior to other vehicles in its class in every important consumer category. (http://www.fuelcells.org/FCX_Clarity_competitors_comparison.pdf ) The scalability of fuel cells and portability of hydrogen make it possible to envision a green transportation future that preserves consumer choice. The benefits have been estimated and re-estimated. Despite the Sturm und Drang on the blogs, nearly all hydrogen pathways produce benefits compared to conventional pathways, even the Prius, and the best hydrogen pathways are the most benign known motor fuel pathways. (www.its.ucdavis.edu/education/classes/pathwaysclass/9-LCA(Delucchi).pdf, among many others.)
There are significant challenges ahead. Durability is improving but still short of commercial acceptability. Vehicle cost must come down dramatically, though the path to affordability is no longer a mystery – the engineers know what to do to get costs down and they are working on it.
Fuel cost is no longer a barrier – even today hydrogen is cost competitive with gasoline per mile driven, due to the exceptional conversion efficiency of the fuel cell vehicle (Honda estimates 60% efficiency, compared to perhaps 15% for a conventional combustion engine).
Deploying the infrastructure to deliver hydrogen to consumers is also a challenge, but the National Academy of Sciences (see above for cite) estimates that for $16 billion – that’s right, $16 billion, just $8 billion from federal sources – we can deploy sufficient infrastructure to support five million vehicles, and reach profitable volumes in both fuel and vehicles. The National Academy identified vehicle cost as the largest component requiring incentives. But the study estimated that covering the entire difference in price between a base vehicle and fuel cell vehicle over 15 years would cost just $40 billion. (NAS 2008, p. S-11) At that point, the transition to a combustion-free, fully capable, consumer friendly and commercial fuel cell electric vehicle would be fully taken up and completed by the marketplace.
This is not pie in the sky. It is a sound option, supported by spectacular engineering accomplishments and by analysis as unbiased as we can find in today’s world. The auto industry has concluded that smog, global warming regulations and volatile energy prices and/or fuel scarcity will limit their markets in coming decades. They have set out to develop a highly efficient vehicle with low environmental impact. And they chose to invest so many billions of dollars of their own money in fuel cells only after a serious analysis of the other pathways.
I don’t expect everyone to jump on the band wagon, but let’s have a serious discussion based on what these technologies really offer today, and tomorrow, their costs and economic viability, today and tomorrow, and their ability to contribute to the national goals of energy security and climate stability.
I have thought long and hard about what it is that invites such enmity toward hydrogen from otherwise civil and thoughtful people. This animus seems exceptional to me even in the blogosphere. There are still probably some people who believe hydrogen is part of a plot to avoid stronger motor vehicle mileage regulation. There are some who believe (wrongly) that hydrogen research siphons excessive dollars from other advanced and renewable energy research. But I think there is also a collective anxiety about the cost and supply of motor fuel created by $4.50 a gallon gas. We seek the reassurance of simple and simply understood “solutions.”
The idea that by simply putting a little bigger battery in our cars and charging up overnight we can get 150 or even 300 miles per gallon and solve our energy problems is beguiling, but false. But the simple fact is that all the pathways present cost, technology, infrastructure and consumer acceptance challenges. All the pathways will take years to bear fruit. And all the pathways – including hydrogen - will need to make a contribution if we are to achieve our energy security and environmental goals.