We are talking of vast quantities of hydrogen exported, to be used as a
fuel.
Publically sourced objective information is difficult to find,
yet this is a bipartisan government declared / government subsidised major
initiative that will affect all Australians
.
Hydrogen gas is described by colours depending on how it is made
White hydrogen - naturally occuring from rare underground
sources
Brown hydrogen - from conversion of coal
Grey hydrogen – extracted from oil and natural gas producing
greenhouse gases that contribute to global warming.
Blue hydrogen – is as above but the carbon emissions in the
production process are captured, sequestered, or repurposed so that
they do not contribute to global warming.
Turquoise hydrogen - experimental - from natural gas
(methane) at high temperatures producing hydrogen and solid carbon
Pink hydrogen- from nuclear energy
Yellow hydrogen- electrolysis from a mix of renewable and
non-renewable electricity sources.
Green hydrogen – is produced from zero-emission renewable
energy by electrolysis of fresh water
In current thinking, in Australia, there are two economically viable
methods to produce hydrogen. Depending on the type of energy input, both
methods may produce carbon dioxide waste either directly or through using
fossil fuels to provide the electricity.
Hydrogen H2 produced by the electrolosis of clean, fresh
water H2O
--> Green Hydrogen is produced if the
electricity comes from renewables or...
--> Yellow Hydrogen if electrticity is wholly or
partially from non-renewables
Hydrogen H2 produced from Methane CH4
"natural gas"
--> Grey Hydrogen is produced if not all waste CO2
is contained and/or electricity from fossil fuels is used in hydrogen
production or...
--> Blue Hydrogen if CO2 from extraction,
processing, transport and any non-renewable electricity is totally
sequestered.
If fresh water is used, as a dry continent, with
municipal and agricultural acitivities periodically affected by drought,
large scale Hydrogen production sourcing surface and near surface fresh
water appears problematic.
If fossil fuels are used in the short term or long term directly or
indirectly in the production of H2 hydrogen then questions
need to be addressed as to what happens to the resulting CO2
carbon dioxide pollution both in the short term and in perpetuity.
So in addition to hydrogen production itself, questions need to be
addressed regarding CCS Carbon Capture and Sequestration
Our ethical assumption is that this hydrogen
production will not directly or indirectly result in additional
atmospheric pollution now or at any time in the future.Some questions
need to be addressed, the answers made clear to the public before
large scale production begins.
Questions about Hydrogen H2 produced by the
electroloysis of water H2O
What portion of export hydrogen production will derive from the
electrolysis of fresh water?
Australia is one of the driest continents on the planet
historically and frequently subject to prolonged drought. At 100%
efficiency it takes about 9kg of water to produce 1 Kg of hydrogen
gas. So where are we going to obtain the necessary vast volumes of
clean fresh water and will this new use for fresh water affect
domestic / agricultural supply?
Large amounts of electricity are necessary to produce hydrogen H2
via electrolysis from water H2O. From the outset is the
electricity to come from renewable or non-renewable sources.?
If electricity from non-renewable sources contemplated how will
the carbon dioxide pollution be permanently dealt with?
Questions about hydrogen H2 produced from
processing methane CH4 "natural gas"
At a theoretical 100% efficiency 16Kg of methane CH4
will create 44Kg of carbon dioxide CO2 waste and produce
4Kg of hydrogen . So the ratio by mass of waste to product is 10:1,
how is this large mass of waste captured and dealt with?
After processing the Hydrogen retains 15% of the energy from the
source Methane. Where does the other 85% of the energy go?
What is the current efficiency of methane and carbon dioxide
containment at the wellhead and in transport to the conversion
facility?
What is the current industrial scale efficiency of methane to
hydrogen conversion?
What is the current industrial scale efficiency of carbon dioxide
capture from methane to hydrogen conversion?
"Natural gas " at the wellhead may contain about 10% carbon
dioxide plus other atmospheric pollutants such as sulphur dioxide.
How are these waste wellhead gases removed, captured and dealt with?
How are leaked methane and carbon dioxide from joints, faults,
fractures in the geological strata, from around the wellhead, around
old wellheads or in transmission to the conversion facility
captured?
The process of separating the hydrogen from carbon requires
high-pressure steam, presumably heated by burning some of the
mehtane. How is the carbon dioxide from this burning dealt with.
For export the hydrogen is converted and compressed to ammonia NH4.
How is the carbon dioxide produced by large amount of energy
required for conversion ; get captured and dealt with?
What is the current overall industrial scale efficiency of Carbon
Capture Sequestration from all the above sources in the conversion
process?
Minimum conditions necessary for a geological. structure to be
considered for CCS Carbon Capture Sequestration
a suitable geologicallly stable structure must an extensive, flat
lying continuous layer and remain so in perpetuity
the layer of "host rock" must be at a minimum depth of about 2
kilometres so that overlying crustal pressure keeps the carbon
dioxide waste liquiified
free of folds, joints, faults, fractures, deformation (so there can
be no CO2 leakage vertically)
that terminates on all sides by thinning out to zero thickness
essentially "pinching out" (so there can be no CO2 leakage
around the periphery).
the "host rock" should havewith lots of space between the
grains (porosity) and
lots of connectivity between the spaces (permeability)
it must be overlain by at least one extensive continuous
another continuous sealing "cap" rock layer above to keep the heated
(50-60 degree Celsius) pressurised liquid carbon dioxide from
expanding and migrating upwards.
the structure must be able to contain the carbon dioxide waste
forever so it must occur in a perpetual depositional environment and
not an erosional environment
The analogy often given is a bottle of hot carbonated soft drink.
The glass bottle is the"host" rock.
The metal cap the "cap" rock.
The hot soft drink fluid, the contained and pressurised carbon dioxide.
Like in the analogy, if the cap gets ruptured, the pressure is released
and the carbon dioxide rapidly bubbles out
The elephant in the room in all of this is that in order to contain the
vast volumes of pressurised carbon dioxide, the "host" and "cap" rock
layer must remain intact in perpetuity.
longer than the pyramids
longer than it takes high grade nuclear waste to decay to a safe
level
longer than it took Australia to drift at a couple of centimetres
per year from South America
the cost of monitoring and maintaining the pressurised for millions
of years must be factored into the cost of the hydrogen fuel
Run away carbon dioxide leakage post sequestration would have catastrophic
results from local to global scales
for example:
if on land suffocation of all oxygen life -->particular concern,
people, crops and animals
creation a lethal environment in which to affect a repair of the
leak
if in water, acidification of the water resulting in death of
marine life --> of particular concern fish
at scale the potential for run away very rapid greenhouse effect in
a very short time frame, at a rate unprecedented in human history
loss of containing pressure in the rock layer for example from an
earthquake would likely result in explosive expansion of liquid to gas
CO2 leakage up a fault or joint into a populated area,
could have catastrophic results. For example : Lake Nyos is a crater
lake in the Northwest Region of Cameroon that gives off periodic
deadly explosive bursts of CO2 that resulted in the
suffocation of people and animals
Questions about CCS Carbon Capture Sequestration of Carbon Dioxide CO2
Is the cost of sequestered CO2 monitoring in perpetuity
factored into the cost of the export hydrogen?
Has the cost of maintaining the integrity both land based and ocean
based wellheads in perpetuity been facored in to the export price?
What legislation is envisaged to ensure monitoring and oversight,
safety and immediate funds to deal with emergencies are
maintained in perpetuity?
Will this Legislation be retrospective to cover CCS that has already
taken place.
Does the Constitution require changes to prevent future governments
from negating the legislation? - we are looking at thousands of years
Does technology and methodology exist to seal and contain CO2 blowouts
and will fast reaction teams be available on standby in perpetuity?
What procedures are in place to assure that blowouts do not endanger
the public?
Who is liable (in perpetuity) should a catastrophic event occur on
land or in the sea?
Currently sequestration is taking place near methane extraction
points. When that is not feasible how will the carbon dioxide be
transported from the site of production to distant sequestration
sites?
Lots of questions - few answers - page will be updated when public
information of sufficient depth becomes available