In spite of enthusiastic politicians, hydrogen is a carrier, not a source of energy. Read on...
Fuel Cells in Wikipedia
"The round-trip efficiency (electricity to hydrogen and back to electricity) of such plants is between 30 and 40%"
Our Transportation Energy Future F. David Doty – [2004 March]
"[T]he 'Hydrogen Economy' will never materialize and our only viable, long-term option is renewables. ... [H]ydrogen has order-of-magnitude disadvantages in fuel costs, engine costs, and CO2 release that will not be solved in the next five decades."
Is Hydrogen the Solution? Hydrogen fuels have long-term promise, but we need to act now to relieve dependence on foreign oil and reduce global warming pollution. NRDC [2004 April]
"Hydrogen fuel cells and fuel sources, however, face significant technology, cost, and deployment barriers. A practical assessment of these barriers reveals that it will take at least two decades before hydrogen and fuel cells can begin to make a significant contribution to our energy security, cleaner air, and a safer climate."
A better way to get from here to there: A commentary on the hydrogen economy and a proposal for an alternative strategy, David Morris, Institute for Local Self-Reliance [2003 December]
"The idea of a hydrogen economy has burst like a supernova over the energy policy landscape, mesmerizing us with its possibilities while blinding us to its weaknesses. Such a fierce spotlight on hydrogen is pushing more promising strategies into the shadows.
The hydrogen economy is offered as an all-purpose idea, a universal solution. However, in the short and medium term a crash program to build a hydrogen infrastructure can have unwanted and even damaging consequences. This is especially true for the transportation sector, the transformation of which is the primary focus of hydrogen advocates and the highest priority of federal efforts. "
The Hydrogen Hallucination The “Freedom Fuel” Leaves Us in Chains, Mark Sardella, PE [2003 June 17]
It’s being called the “freedom fuel”, capable of releasing us at last from the grip of the oil barons. The “hydrogen economy” is even the buzz of the bestseller list. But don’t break out the party balloons yet, because hydrogen hasn’t even the slightest chance of solving our energy problems. A bold assertion, perhaps, but the proof is contained in the simplest of facts: Hydrogen is not a source of energy.
The Future of the Hydrogen Economy: Bright or Bleak? Ulf Bossel, Baldur Eliasson, Gordon Taylor [2003 April 15]
"In this study, the energy consumed by each stage is related to the true energy content - the higher heating value (HHV) - of the delivered hydrogen. The analysis reveals that much more energy is needed to operate a hydrogen economy than is required for fossil energy supply and distribution today. In fact, the input of electrical energy to make, package, transport, store and transfer hydrogen may easily exceed the hydrogen energy delivered to the end user - implying a well-to-tank efficiency of less than 50 per cent. However, precious energy can be saved by packaging hydrogen chemically in a synthetic liquid hydrocarbon like methanol or ethanol. To de-couple energy use from global warming, the use of "geo-carbons" from fossil sources should be avoided. However, carbon atoms from biomass, organic waste materials or recycled carbon dioxide could become the carriers for hydrogen atoms. Furthermore, energy intensive electrolysis may be partially replaced by the less energy intensive chemical transformation of water and carbon to natural and synthetic hydrocarbons, including bio-methanol and bio-ethanol. Hence, the closed natural hydrogen (water) cycle and the closed natural carbon (CO2) cycle may be used to produce synthetic hydrocarbons for a post-fossil fuel energy economy. As long as the carbon comes from the biosphere ("bio-carbon"), the synthetic hydrocarbon economy would be far better than the elemental hydrogen economy - both energetically and thus environmentally...
"... We have examined the key stages by physical and chemical reasoning and conclude that the future energy economy is unlikely to be based on elemental hydrogen...
"The analysis shows that an elemental "Hydrogen Economy" for road transport would have a low well-to-tank efficiency and hence a low environmental quality. In particular, if the electrical energy were generated in coal-fired power plants, the well-to-tank efficiency might fall below 20%. Even if the hydrogen were used in fuel cells, the overall energy efficiency would be comparable to that of steam engines in the early half of the 20th century, while the CO2 emissions would have significantly increased due to the growth of overall energy consumption.
"The time has come to shift the focus of energy strategy planning, research and development from an elemental “Hydrogen Economy” to a “Synthetic Liquid Hydrocarbon Economy”. This means directing the limited human, material, and financial resources to providing technical solutions for a sustainable energy future built on the two closed clean natural cycles of water (for hydrogen) and CO2 (for carbon). Fortunately, much of the technology exists already – e.g. for growing biomass, and for fermentation and distillation to produce ethanol. Both methanol and ethanol could be synthesized from water and carbon. Provided that the carbon is taken not from fossil resources ("geo-carbon"), but from the biosphere or recycled from power plants ("bio-carbon"), the "Synthetic Liquid Hydrocarbon Economy" would be far superior to an elemental "Hydrogen Economy", both energetically and environmentally."
We hear a response to this: A Few Basics About Hydrogen. This is part of an article entitled 20 Hydrogen Myths, by Amory Lovins [2003 June 23]
"[Myth] Delivering hydrogen to users would consume most of the energy it contains.
"Wrong. Two Swiss scientists recently analyzed the energy needed to compress or liquefy, store, pipe, and truck hydrogen. Their net-energy figures are basically sound—but their widely quoted conclusion that because hydrogen is so light, "its physical properties are incompatible with the requirements of the energy market" is not. In fact, their paper, published by the competing Methanol Institute, simply catalogues certain hydrogen processes that most in the industry have already rejected, except in special niche markets, because they're too costly, including pipelines many thousands of kilometers long, liquid-hydrogen systems (except for rockets and aircraft), and delivery in steel trucks weighing more than one hundred times as much as the hydrogen carried.
"The authors also focus almost exclusively on the costliest production method—electrolysis. They admit that reforming fossil fuel is much cheaper, but reject it because, they claim, it releases more CO2 than simply burning the original hydrocarbon. That ignores the hydrogen's more efficient use: even under conservative assumptions about car design, a good natural-gas reformer making hydrogen for a fuel-cell car releases between forty and sixty-seven percent less CO2 per mile than burning hydrocarbon fuel in an otherwise identical gasoline-engine car, because the fuel cell is 2–3 times more efficient than the engine.
"Even more fundamentally, the Swiss authors analyzed only costly centralized ways to make hydrogen. Most industry strategists suggest—at least for the next couple of decades—decentralized production at or near the customer, using the excess off-peak capacity of existing gas and electricity distribution systems instead of building the new hydrogen distribution infrastructure whose costs the Swiss analysis finds so excessive.
In turn, this entire article is challenged in “Twenty Hydrogen Myths”: A physicist’s review by Dominic Crea.
"This article is being written in response to a recent paper by Amory Lovins —“Twenty Hydrogen Myths”—and wishes to identify what this author believes are a series of errors and misleading statements contained in that document. Doubtless, this paper will find itself questioned in turn; this is encouraged since an active and healthy debate amongst concerned scientists, engineers and the general public will ultimately clarify rather than confuse the issues surrounding the Hydrogen Economy."
Perspectives on Fuel Cell and Battery Electric Vehicles Alec N. Brooks, AC Propulsion, Presented at the CARB ZEV Workshop [2002 December 5]
"But are fuel cell vehicles really the holy grail – the end game for providing clean personal mobility? The popular and accepted view is that they are. The thinking goes along the lines of: fuel cells far more efficient than an IC engines because they are based on an electrochemical process rather than combustion; they are quiet, there are no moving parts, no greenhouse gas emissions, only pure water for emissions, and will have far more range than battery electric vehicles. It sounds great.
"But today I want to share with you some perspectives on fuel cell and battery electric vehicles that differ from the conventional wisdom..."
The debate continues...