[extropy-chat] Hydrogen a "bad Idea"
Thomas at thomasoliver.net
Thu Apr 12 08:12:16 UTC 2007
Keith Henson wrote:
>I must say that several threads have become more noise than signal.
I hope this help, Keith:
[...] 'Save the planet' technologies.
01. Make Oil from Just about Anything.
02. Desalination, removing the salt and minerals out of seawater.
03. Hydrogen fuel cells.
04. Solar power developments.
05. Ocean Thermal Energy Conversion.
06. Harness Waves and Tides.
07. Plant Your Roof. Roof gardens are a good thing.
08. Let Plants and Microbes Clean Up After Us.
09. Bury The Bad Stuff. Put CO2 in the ground.
10. Make Paper Obsolete. Re-usable electronic paper.
03. Hydrogen fuel cells.
This is a *bad* idea. It has been shown that
running on hydrogen is much less efficient than running on "electricity".
You lose too much energy in the production, transport and/or storage
of the hydrogen. Methanol or ethanol fuel cells would be far better
so long as the methanol or ethanol are being produced from carbon
extracted from the atmosphere. All hydrogen now used comes from
methane and the only way you can produce it relatively cheaply is to
oxidize the carbon in the methane and release the CO2 into the atmosphere.
The only other common source of hydrogen is water and until someone
comes up with a catalyst that uses solar energy to cheaply split water that is too expensive as well.
If you *really* want this it should be:
03. Hydrogen fuel cells + Catalyst to produce H2
from H2O+sunlight + Lightweight H2 storage system.
If you want to store CO2 produced by power plants
underground and use the electricity to charge batteries for transport
you have a much more efficient system. Better still if you can take
the plants (or bacteria) on your roof to convert your solar energy directly into either ethanol or electrons to feed to your means of transport.
So alternatively you might want:
03. Lightweight nanotechnology high capacity based
capacitors that can rapidly and efficiently charged.
We are *much* closer to that than we are to having
a hydrogen solution.
I ran this by Paul Torgerson of Worldwide Energy, an emerging hydrogen fuel cell/electrolyzer company. He had this to say:
These are all very noble claims being made by people with litlle
concept of the challenges faced today.
The Bureau of Transportation Statistics estimates that there are
234 million light duty vehicles, cars, and motorcycles registered
in the United States in 2004. These vehicles consumed 138.8 billion
gallons of gasoline and diesel fuel annually. Do we honestly think
we can replace that with solar panels?
Solar panels are by far the most expensive means of energy
production around. To power just US housing would take an
estimated area the size of Arizona, and we build about 15
million new homes a year. The sun only shines part time.
Puttting a solar panel on your roof is not enough to solve
the energy crisis.
The hydrogen economy has already been implemented.
Very high temperature nuclear electrolysis looks like the
cheapest means of hydrogen production. This will use
electricity and heat to crack water molecules. The new
GEN IV light water reactors being developed by DOE won't
be ready until 2030.
[Paul clarified with the following:)
Current US annual hydrogen production is the equivalent of 71.8 Gigawatts
Thermal ("GWth") of nuclear or fossil power. This equates to 118 nuclear (or
fossil) plants to supply the hydrogen using the projected system
configuration of 600 Megawatts Thermal ("MWth") nuclear to 50 MWth for
Hydrogen Production. More than 500 nuclear reactors (or fossil plants, with
carbon sequestration, will be needed by 2050 to achieve the DOE's goal of
substituting 25% of liquid transportation fuel with hydrogen.
If the Company captures five to ten percent market share of this potential
market, Worldwide's metal-tubular solid oxide electrolyzer cell ("MTSOEC")
stack production would grow to thousands of WET multi-megawatt MTSOEC stacks
containing from 468,750 to 937,000 linear feet of WET produced electrodes,
from commissioning of the first commercial reactor (in 2025) through 2050.
Worldwide estimates that each nuclear hydrogen plant using its MTSOEC stacks
will require four to five complete stack change outs over the 60 year life
of the reactor.
This estimate is based on typical 94.5 % reactor availability, typical
baseload operation and maintenance practices, and industry standard run
times between shutdowns.
A 600 MW Gen IV nuclear plant, utilizing high temperature electrolysis, has
the potential to produce 200,000 gallons of gasoline hydrogen equivalent
("gge H2") for less than $2.00/kg . This potential daily production level is
based on 50 MW of thermal energy producing the required amount of hydrogen.
The cost estimate is based on 50% electrolysis efficiency. The estimated
active electrode area is approximately 200 square meters per site.
[end of clarification message]
They estimate that it will take
thermal nuclear hydrogen plants putting out 600 MW to
produce 25% of the energy used in the US in 2050. That's 25%.
Try getting that much energy from bacteria or plants.
Currently, 9 million tons of hydrogen is produced annually
in the United States for non-transportation uses including
petrochemical applications,fertilizer, metals treating,
electronics, and glass manufacturing. Nine million tons of
hydrogen is projected to be able to fuel 20 - 30 million cars
& light duty vehicles (8.5% - 13% of the current vehicle population)
or 5 - 8 million homes.
Five percent of the natural gas in the United States is used to
produce hydrogen. More than 95% of the hydrogen currently
produced is by a process known as steam reforming from natural
gas. This process is well established, near its theoretical limits,
and is currently several times more expensive than gasoline. In
addition, the future commodity prices for hydrogen produced by
this process will be closely linked to the commodity cost of
natural gas. Making the process cleaner would add to the cost.
Nuclear hydrogen has an estimated cost of $2/gal of gas
equivalent (GGE). Plus nuclear electrolysis doesn't produce
CO2. Burning methane produces CO2, so does burning ethanol.
People riding the bio fuels wagon think a bunch of ethanol plants
can suddenly solve the world's energy needs. In fact, ethanol costs
more to make than its worth. It creates the next big problem of
having to use our food supply to make it in volume.
The DOE is spending big bucks working on carbon sequestration. One of
the most novel uses I've seen is pumping it down dry oil wells. It actually
fills the voids and makes the wells produce more oil.
There are no easy answers to the worlds energy crisis. We'll never have
the magic power to crack enough water into hydrogen with solar energy
to produce 138 billion GGEs a year. DOE is investing billions in the future,
but the ideas below don't merit the energy spent to send the message.
Who can provide a solution with verifiable facts and figures, that supplies
138 billion GGEs a year for 330 million US vehicles, using solar, bio-fuels or
plants on their roofs? Then try fueling 700 million vehicles worldwide, Then
work on heating the couple of billion homes. Once you solve these issues,
work on energy to drive the world's industries which increases at about 5%
And once you solve the US energy needs try taking on China where we expect
the majority of the world's oil production this century to be consumed.
Small scale ideas look foolish when we confront the big picture and become
better informed people.
Paul suggested checking out the Energy Information Agency site <http://www.eia.doe.gov/>.
I bet he'd like your space elevator. --Thomas
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