Opinion: Hydrogen Economy Or Electricity Economy?
The nuclear energy industry
should not overlook its primary mission of generating
carbon-free electricity cheaply in an attempt to embrace
a hydrogen-led future, writes Professor David Barber, who
holds degrees in physics, radioecology and chemical
engineering, and is a member of the Fuel Cycle Division
at the US Idaho National Laboratory. Mr Barber can be
contacted directly by e-mail at firstname.lastname@example.org.
There are two conclusions of relevance to the US nuclear
energy community. First, hydrogen has a critical
inefficiency problem that is rooted in thermodynamics.
This is essentially unsolvable and renders hydrogen
impractical as either an energy carrier or an energy
storage tool. Second, economics, technical practicality
and the urgency of strengthened national security through
energy independence, all mean electricity is the
overwhelming favourite as the energy carrier that will be
carrying stationary-source energy to the transportation
sector in the 21st century.
Long before hydrogen becomes feasible, the less-expensive
energy carrier – electricity – will have already
captured much of the US transportation market. Therefore,
the US nuclear energy community would be well advised to
sidestep hydrogen and focus, over the next several
critical decades of nuclear renewal, on its fundamental
issues: passive safety, proliferation resistance and
closing the fuel cycle. This would ensure that nuclear
energy continues to be available, viable and sustainable
as the lowest-cost provider of grid-distributed
It should be noted that the hydrogen industry accounts
for a relatively trivial sliver of the overall national
US energy budget. Capturing the present hydrogen market
is certainly not the big hydrogen opportunity that would
justify the investment to develop dedicated nuclear heat-based
hydrogen production plants. As long as transportation
continues to be based on petroleum, there is no big
hydrogen opportunity worthy of a dedicated plant level of
Nearly all hydrogen in use today is itself being “produced”
by stripping hydrogen from natural gas through steam
reformation of methane. There is no technical advantage
to reforming methane in preference to electrolysis of
water; there is only a price advantage of about a factor
of two. Today, natural gas is trading with a floor price
of about five US dollars (USD) per MBtu. That price will
need to rise permanently above USD 9 per MBtu before
methane reformation will quantitatively yield the
hydrogen supply market to electrolysis using electricity
costing four US cents per kilowatt hour (kWh) (all
figures based on 2004 valuations).
The truth about whether hydrogen best serves national
security and energy independence goals depends upon how
its burden of application weighs on the national economy
in comparison to other options. A hydrogen vehicle using
hydrogen derived from coal-fired electricity is actually
several times more polluting than a gasoline-powered
vehicle. Surprisingly, many conversations with attendees
at the 2004 meeting of the National Hydrogen Association
and much of the present literature reveal that many
hydrogen enthusiasts don’t make the distinction between
energy carriers versus energy source.
Basic conversion and handling losses waste most of the
energy. The result is that for every four power plants
making electricity, only one plant’s electrical output
actually ends up being productively used. Three power
plants’ output is lost simply because hydrogen is part
of the process. That level of waste is unacceptable in
any situation, particularly at a time of global energy-related
Long before petroleum is depleted and future generations
are considering a replacement “fuel”, electricity
will have already captured a vast portion of the
transportation market through a very simple and
predictable maturation of today’s hybrid technology.
Why will this happen? Because electricity is cheaper.
If you think people might resist a change from quick
fuelling at the petrol station to overnight charging,
think again. A 2001 study by the US Electric Power
Research Institute found that most people surveyed
preferred plugging in a vehicle to filling up at a petrol
station. Overnight charging perfectly fits our present
grid functioning, which tends to be electricity rich
during night-time off-peak hours.
After being attacked at every turn through our history,
the US nuclear energy community might have trouble
believing that something may actually go well for us.
Nevertheless, we are perfectly poised for the only
legitimate opportunity to extend stationary-source energy
to the transportation sector this century. Rather than
speculation on a revolution in transportation based on a
thermodynamically inefficient fuel and an altogether new
infrastructure, perhaps we should notice that the
transportation evolution – based on a familiar energy
carrier and existing technology – has already begun.
The strength of the relationship between the hydrogen
economy and renewables cannot be overstated. The wind
doesn’t always blow and sunlight isn’t always
striking every solar panel. Renewable energy desperately
needs a very big battery, a load leveller. Without some
form of energy storage, renewables are physically limited
to less than a 20% share of the grid. At 20%, renewables
are more of a headache than a resource for a grid manager.
The hydrogen economy is not really about energy security
or clean air. The hydrogen economy is a backdoor attempt
to integrate renewable energy’s desperately needed load
leveller into general commerce.
My advice to fellow greens in the renewable energy
community is as follows: recognise that the 25% loop
efficiency problem with hydrogen is essentially
unsolvable because it is rooted in thermodynamics –
hydrogen is a lousy load-leveller. Instead, work to
minimise the weather-dependent grid limitation problem of
renewables by focusing on improvement of the North
American grid infrastructure and encouraging utilisation
of more efficient electricity storage tools.
However, reducing greenhouse gas (GHG) emissions in
transportation with hydrogen or methanol would be much
more expensive per unit of GHG reduction. Consumers would
need convincing to pay for all of the additional plants
and all that new infrastructure, in addition to buying
the much more expensive, fuel cell-based vehicles – all
for the pleasure of using a fuel that is several times
more expensive than electricity.
There are two messages here for the US nuclear energy
community. First, for GHG emission reduction, coal-fired
plants are the low-hanging fruit. Coal’s own estimates
are two to three additional cents per kWh to separate
carbon dioxide and inject it into subsurface geologic
formations. Coal simply doesn’t have that price margin
relative to nuclear – regardless of the fact that
utilities are planning more than 100 gigawatts of
electricity generating capacity from new coal plants.
When coal’s long-enjoyed externalities finally come
home to roost, the coal industry will not be able to hide
the facts that coal is both the dirtiest and the most
easily replaced form of fuel. That’s 50% of the US grid
up for replacement. That most certainly is not a trivial
sliver of the overall national energy budget.
The second message is that the most economical and
probably only economically viable way to reduce GHG
emissions (and oil imports) in transportation is to
support and encourage the hybrid evolution by providing
clean, economical electricity.
Electricity is mankind’s cleanest, most-efficient
energy carrier. Nuclear energy is mankind’s only non-greenhouse
gas emitting energy source that is available around the
clock, regardless of the weather.
There is no conceivable future energy scenario in which
nuclear energy will be more heavily used than to make
electricity for the grid.
There are significant challenges to a hydrogen energy
carrying scheme. These include materials development,
tremendous cost barriers, infrastructure inadequacies and
the very low conversion efficiency. While many of
hydrogen’s problems could be reduced with enough time
and effort, the fact remains that the 25% efficiency
problem of the electricity to hydrogen to electricity
loop is unsolvable. Societies worldwide will be
struggling this century and beyond just to afford to
replace their existing GHG-belching stationary sources
with clean, non-GHG sources like nuclear, wind, low-heat
hydro and solar. There certainly will not be an
overabundance of clean energy to squander on an
inefficient hydrogen loop, particularly when the same
tasks can be accomplished directly with the original
electricity. Not this century, anyway.
Not even nuclear energy can turn hydrogen into a winner.
To be sure, direct heat nuclear can easily beat that –
our hydrogen would be only twice as expensive as our
electricity. Nuclear easily wins the hydrogen game.
However, that victory in making hydrogen is moot. The
hydrogen car costs much more than the PHEV (pneumatic
hybrid electric vehicle). The new hydrogen distribution
infrastructure costs much more than the grid. The
cheapest hydrogen still costs more than electricity and
always will. Nuclear can easily win the hydrogen game,
but hydrogen itself is a loser.
Most of the needed grid growth and coal replacement will
go to nuclear if critical mistakes – like seeing our
reactors closed because there is no path for large
volumes of low-power density, once-through spent fuel –
Nuclear growth is inevitable. The US nuclear energy
community should ignore the hydrogen red herring and
concentrate on our fundamental issues, particularly
reversing the mistake of the 1970s by redeveloping core
skills in waste volume and proliferation risk
minimisation through closing the fuel cycle. This would
ensure that nuclear energy continues to be available,
viable and sustainable as the lowest-cost provider of
Electricity will always be nuclear energy’s primary
Zdroj: NucNet, David Barber
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