If I said the word hemp to you, I wonder what image it would conjure up in your mind.
I guess it could mean many different things depending on your own life experiences.
As you probably know, hemp is a variety of the cannabis sativa plant. It grows pretty rampantly,
very much like a weed. Which is probably why some people call it weed! But to associate it only with
that particular recreational activity is to do it a severe disservice. Hemp is in fact an extremely
useful and versatile plant. It can grow in all sorts of soils and climates with little or no need
for pesticides or fertilizers. We humans have been using it to make fabrics for thousands of years.
It's six times as strong as cotton and much much less environmentally impactful to grow.
Our English King Henry VIII actually made hemp cultivation mandatory during his reign in the
16th century - not because he was particularly partial to a nice long evening chill-out session,
he was more of a chicken drumsticks and mead kind of a guy, but because the fibres in hemp
made extremely good quality ropes. And that was very handy for the rigging on all his ships.
During the latter half of the 20th century the whole 'it's made of cannabis'
thing convinced successive governments to look less favourably on the humble hemp plant
even though the variety grown for non-drug applications contains low or even negligible
levels of the psychoactive THC component that seems to terrify some legislators so much.
Now though, hemp is staging a bit of a comeback. Along with bamboo it's one
of the fastest growing plants on the planet. And that makes it an extremely good candidate
for rapidly capturing carbon back out of our atmosphere. The challenge is where to grow
it without destroying already existing ecosystems and biodiversity. And that's a lesson the world's
learnt through bitter experience with crops like corn soybeans and sugarcane to name just a few.
So how about this for a concept... build a big hydroponic crop growing warehouse on an industrial
estate somewhere, a bit like the vertical farms we've all seen in the news recently,
only instead of lettuce and kale grow hundreds of tons of hemp and then use it to make useful things
that capture the carbon content permanently. Sounds like a plan doesn't it? And that's
exactly the mission currently being pursued by a Florida-based company called Carbotura. So the
question is... can hemp become a trailblazer for the 21st century carbon capture program
that'll be essential to keeping our global atmospheric temperature below 1.5 degrees Celsius?
Hello and welcome to just have a think. Regular viewers will know that we've talked about carbon
capture and sequestration or CCS several times on this channel. Pulling carbon dioxide back
out of the atmosphere is, according to the IPCC, and most other climate scientists,
the only way we stand any chance of stopping our global atmospheric temperature reaching
existentially dangerous levels. But exactly how we achieve that goal has become a very contentious
issue. Carbon capture from the exhaust stacks of factories and coal and gas-fired power stations
adds about 20% to the cost of operating those plants, so it really hasn't been widely adopted.
Bioenergy and carbon capture or BECCS, is disputed by many environmental groups as
a true carbon capture method, at least in its current form, because when the fuels are burnt
they release CO2 straight back into the atmosphere faster than the replacement crops can
pull it back out again. And the change in land use required to grow those crops impacts heavily on
indigenous plants and animals. Direct air capture, which uses mechanical fans to suck air across a
chemical concoction that reacts with the CO2 to remove it, is also looking somewhat fanciful. It's
pretty expensive and we'd need literally millions of facilities all over the planet to get anywhere
close to offsetting the 40 gigatonnes of CO2 that modern human activity currently spews out. So the
concept of hydroponically growing hemp in huge closed loop systems on brownfield sites looks like
it really could play a genuinely important role in contributing towards the carbon capture challenge.
Carbotura is an environmentally focused company operating within a group called
Gravitas Infinitum. The fundamental basis of the operation is something that Carbotura refer to
as a direct carbon sequestration system or DCS. And those big warehouse style units that'll
house the production facilities are called High Density Biofactories or HDBFs. The HDBFs will
vary in size from 30 000 to 100 000 square feet depending on the location, and in basic terms the
process works like this... just like a vertical farm, thousands of hydroponic growing trays will
be populated with seeds (in this case hemp seeds) and stacked up in warehouse style racking systems.
Carbon dioxide will be pulled out of the atmosphere by the plants during photosynthesis.
A pumped irrigation system will deliver about 400 litres of water to each pallet location
every three hours, which in the largest facilities equates to nearly 60 million litres per day.
Sounds like a terrible drain on precious water supplies doesn't it? But here's the first of
many benefits of the system - that water is continuously recycled as part of the closed
loop cycle, so the overall usage is very low relative to the production throughput quantities.
And the system has the potential to contribute towards cleaning up the contents of wastewater
ponds called stacks which are currently a very problematic by-product of the phosphate mining
industry in Florida and many other locations throughout the United States and wider world.
Phosphate is a component of agricultural fertilizers so it's mined in vast industrial
quantities. If those phosphate ponds are not carefully managed they can contaminate local
water systems with disastrous consequences, as was so graphically demonstrated by the evacuation of
hundreds of residents in Manatee county, Florida over the Easter weekend in 2021 when water levels
in phosphogypsum waste stacks threatened to overwhelm their containment walls
and send a tidal wave of contaminated water into people's homes. But to the hemp plants
in the biofactories that waste water represents a rich source of nutrients that can be used by
the plant's root systems to accelerate growth. The hemp effectively acts like a bio filter
and after about 40 or 50 circulation cycles over a four or five day period the water coming out of
the process will be clean enough to be assessed by local environmental agencies for potential return
back into local lakes and river systems. A large HDBF facility will house up to 38 million hemp
plants with about 600 000 plants being harvested every day. That enormous volume of carbon rich
biomass will then be fed into something called a microwave plasma pyrolysis system.
This is an existing technology normally used for the conversion of solid waste materials
into usable fuels. Essentially it's a very sophisticated industrial scale oven arranged
in a tall stack with the capacity to process a thousand kilograms of biomass every hour.
The system produces different outputs at different points in the combustion process.
At the top of the stack synthetic gas is drawn off, cleaned, condensed and stored.
Then at the next level down heavier oils come out which again are condensed and stored.
But those fuels will be used to drive a turbine providing all the power for the factory's
working systems. And the exhaust gases can even be diverted back into the initial combustion process
to ensure the maximum amount of CO2 is captured. The product coming out of the bottom of the stack
is biochar. That's a commercial product in its own right that's rapidly gaining popularity in
many applications, not least as a soil additive to help deliver large quantities of carbon
back into the earth. But it also provides the feedstock for two other far more commercially
valuable commodities - graphene and industrial diamonds. The biochar is fed into a second chamber
where oxygen has been replaced by argon gas, and that prevents the carbon in the biochar
from oxidizing. Inside the chamber is a 200 kilowatt pulsed plasma reactor - again an
existing technology used in various industrial processes. The reactor converts the biochar into
a product that Carbotura have now trademarked as bio-graphine, which according to them is the
highest purity and lowest cost graphene available on the market. The same plasma equipment can also
make industrial diamonds using another existing process called carbon vacuum deposition or CVD.
Essentially a copper or steel plate is seeded with microscopic fragments of an existing diamond.
The plates are then flooded with high carbon atom atmospheres, again in a deoxygenated
environment. So instead of oxidizing, the carbon atoms crystallize around the diamond seeds,
taking on the same shape and form, growing the diamond layer by layer. That gives you a product
worth something like a hundred thousand dollars per ton that can be used for things like drill
tips and tunnel boring machines. Further down the line the plan is to diversify the
initial raw material feedstocks by setting up separate microwave plasma pyrolysis systems for
solid waste materials and waste plastics. The pyrolysis process dismantles the materials
right down to the molecular level, potentially producing a vast array of end products including
bioplastics, each of which has its own commercial value. But graphene is the focal point for the
first phase of the business. That's where the economics stack up most favourably for Carbotura.
And of course graphene is predicted to become a pretty ubiquitous material for all sorts of
industries in the future. Unlike the fossil fuel industry, this carbon capture process has none of
the upfront costs for discovery and exploration or extraction of materials. In fact once waste
materials and plastics are introduced alongside hemp production as feed stocks, Carbotura will
actually be getting paid a tippage fee of between $35 and $65 a ton to take the waste away.
Both the main hemp biomass and the supply of waste materials are effectively unlimited as
well. Because it's grown inside a closed loop system in an industrial facility there's no
negative impact from the hemp production on existing ecosystems or biodiversity. And as
for the solid waste and plastic - well the more that that gets used in processes like these the
less of it is available for landfill, which can only be a good thing. According to Carbotura, each
large HDBF facility will be capable of capturing about 44 000 tonnes of carbon dioxide every year,
which is not only a net benefit to our warming atmosphere but also yet another revenue stream
thanks to current US incentives for CO2 capture, including carbon sequestration credits of about
twenty dollars a ton and a federal tax credit called 45Q worth 32 dollars for every tonne of CO2
sequestered. And of course the price of carbon and carbon credits is only going to increase over the
coming years as efforts to reduce atmospheric CO2 levels accelerate all over the world. The direct
carbon sequestration system has won selected project status with the U.S department of energy
and Carbotura are in the final stages of securing funding for the first round of construction
which is scheduled to start in southwest Florida later this year. There's no doubt this is a very
ambitious and groundbreaking initiative. You could also argue it's yet to become a proven technology,
and that might feel a little intimidating to some investors. But projects like this,
and others that are in development elsewhere in the world, are precisely the kind of thing that
will be required on a massive global scale if the challenge of removing billions of tonnes of carbon
dioxide from our atmosphere stands any chance of succeeding. And I know I'm starting to sound like
a bit of a broken record here but it's always worth reminding ourselves that these pioneering
companies also represent the future employment opportunities for our kids and grandkids. This is
quite a complex concept at first glance, it certainly took me some time to properly understand
all the elements at work here. And no doubt it'll provoke some strong reactions one way or another
from you folks out there. So, if you do have constructive and objective feedback that you'd
like to share then jump down to the comment section below and leave your thoughts there.
That's it for this week though. We're taking a short break next week, so there'll be no video
on Sunday the 27th. But I'll be back in my regular slot on Sunday the 4th of July, which I'm given
to believe is a date of some significance to our friends in America! As always my thanks go
to the Patreon supporters who allow me to remain completely independent and help me keep all these
videos ad free, and I must just give a quick shout out to the folks who've joined since last time
with pledges of $10 or more a month. They are Javier Dominguez, Alfred Berkeley, Lark Cyphron,
Peter Ross, Matthew Hunt, Jeff Rink, Lemmie B, Mark Geis, Ranjeev Sandhu, Jessica Feinleib,
and Rogelio Blanco. And of course a big thank you to everyone else who's joined since last time too.
You can check out the Patreon page by visiting www.patreon.com/justhaveathink.com and you can
really support the channel by subscribing and hitting that like button and notification bell.
It's dead easy to do all that, you just need to click down there
or on that icon there. As always thanks very much for watching, have a great couple of weeks,
and remember to just have a think. See in a couple of weeks time