Carbon Sequestration by Leaves - Part 2

Note: If you have not read Part 1 it is strongly advised to read that first.

There are a few misunderstandings about this method I would like to clarify: why, how, cost efficiency, feasibility, etc. I have a tendency to forget to explain things, assuming that people know them already or that my previous writing is self explanatory.

So, let’s break things down. This method is complex and very simple at the same time. Levels are graded from the perspective of carbon locking stability, not profitability.

Level 0: Simplest Carbon Sequestration by Leaves

What is the simplest variation of this method that would sequester large amounts of carbon while avoiding usage of Geoengineering techniques?

Collecting leaves and fallen branches, cutting grown especially dry grass (from hills, savannas, and prairies), additionally drying all biomass to remove as much water as possible, and then just pressing them into briquettes.

Although those briquettes have good caloric value, they should not be burned for heat or energy, as they would release CO2 back again. That means we would need to store them in some dry place where they won’t start decomposing and giving away CO2 on their own (for at least 20 to 50 years), until we switch to clean energy sources.

That’s it! That is the simplest method.

Switching to clean energy sources is critically important. If we don’t, this method or any other won’t help us, and we will face catastrophically more destructive events.

Let’s make a quick cost analysis of preventing the devastating effects of global warming, so let’s calculate how much money we need to do this.

Just the collecting, drying, compressing, and storing part wouldn’t cost more than the method of “Carbon sequestration via wood burial” described by Ning Zeng. He calculated $14/tCO2 ($7–27) (while power plant CO2 capture with geological storage costs $20–270/tCO2) or, in total, $250 billion per year at a 5 GtC y-1 sequestration rate.

Except for building networks of access roads, collecting leaves does not require future tree cutting — bearing in mind that those additional roads would prevent the spreading of wildfires.

Unlike Zeng’s method, the collecting leaves method should be less energy- and cost -demanding, so, in all fairness, it should be cheaper than other CO2 sequestration techniques. The energy needed to dry leaves could be provided efficiently by the sun; compressing leaves by means of a hydraulic press would not take a significant amount of power.

Now, is the $250 billion price tag too big for the entire world to pay?
Again, if we consider the price of damage from Irma and Harvey exceeds $300 billion just in the USA, and add to that price 7 million acres of lost forests, clearly the incentive to fix climate change is already there.
Damage will just continue rising, especially if we take into account that I have not mentioned damage in other places like Puerto Rico, Cuba, or Dominica.

On the other hand, there are geoengineering techniques that are far more dangerous; they come at a higher cost than this technique, and most of them are completely unpredictable.

Imagine if we do not develop any kind of useful products from this point on. At an expense of $250 billion each year, we would fix it. Is it worth it? Of course it is.
That money is not lost; half of it will be spent on machines and the other half on people’s salaries, opening a huge number of jobs. Money spent on this endeavour will find its way back to the economy, increasing GDP.

If we would split the bill (although, in all fairness, fossil fuel companies should pick up the bill) to governments around the world, each of the 195 of them (193 in the UN and 2 non-members) would need to pay ~$1.28 billion each. I am simplifying the calculation by saying that each country needs to make an equal contribution, regardless of its GDP or population size.

Between 2009 and 2012, the United Kingdom released a program called Quantities Easing, in order to boost the economy and reduce poverty and unemployment. The government gave £375 billion ($550bn) to rich people, theorising that the money will somehow trickle down to poor people. They, of course, failed flawlessly—at least from the perspective of the poor and middle class. Money never trickled down; it just stayed in the pockets of rich people who got additional money for gambling on the stock market. Policy makers have not considered a simple truth: the middle class is the motor and foundation of the economy, not the rich people, so this made the economy for the rest of population even more difficult to bare.

Basically, what I am trying to say is this: giving $250 billion around the world through this “leaves collection schema” to the working class would improve those economies. Yes, just by collecting leaves—storing them for the next 20 to 50 years at least, effectively making something that won’t be used by anyone, not even bacteria—would be far more effective for the economies of those countries than Quantities Easing.

Now, let’s make this schema profitable.

Level 1: Making simple products

I hope that by now I have succeeded in convincing you that we could make good just by removing CO2. The climate would stabilise, we would reduce global warming damage, and, additionally, there will be positive economic gain through a schema far better than Quantities Easing. Money would not go to the pockets of rich shareholders but to poor people who would, in return, actually do some good work.

But, we all know we humans are greedy, and we always think about ways to earn more and create more profit. So, let’s do that. Let’s play with few ideas.

What if we create products like paper, cardboard, MDF (Medium Density Fiberboard), or plywood out those leaves?

Leaves have high fiber content, but the properties of similar products may be significantly different from the original; also, the idea is to not ending up with those products on landfills or burning them.
So, whatever we do, we have to keep in mind CARBON LOCKING.
Why? Because carbon was previously locked for million years in the form of coal and oil before we released it back to the atmosphere. Now, we have to find equal amounts of material that will lock that carbon for the next X amount of years.

Someone may ask what tensile strength is or how well it will perform or whether the paper will be equally good. From the perspective of carbon sequestration, it does not really matter, so long as we can keep carbon locked in that form for a very long time. At this point, we can just assume that there is no reason why all those products we make out of leaves should not be comparably good; even if slightly worse, we could still use them as replacements.

Please remember: creating any of these simple products would save a significant number of trees from being cut for the same purpose each year.
As deforestation is one of the major causes of global warming, this would be a significant improvement.

So, there you go: level 1, we already have profitability: instead of paying woodcutters, we would pay leaf collectors, and everything works as before. The economy continues to work just with a few modifications.

At this stage, adjusting policies, working processes, technologies, and machines, and the economy of the usual wood cutting industry would just switch to leaf collection. Therefore, the entire “leaves collection schema” could possibly run with significantly less subsidy money than the previously-mentioned $250 billion. It would be a switch of mindset and using different raw materials.

Using the level 1 schema, we reduced natural emission by 5GtC, saved trees that can continue eating CO2, reduced deforestation that is increasing CO2 and crippling nature’s ability to sequester CO2, and, lastly, we have not used as much money to repair damage.

Level 2: Making something more stable

So, paper, briquettes, cardboard, MDF...they can all end up in dumpsters and landfills, again with the help of bacteria they could start decomposing, releasing CO2 into the atmosphere. It would be beneficial if we recycle those products, so they would still keep carbon (C) locked.
However, the question is, “Could we make something even more stable that will not require later management?”

Biochar is the name for the charcoal that is specifically used for burial (carbon sequestering purpose) and to enrich the soil. The potential issue with biochar was discovered in a 10-year study, revealing that charcoal left on the surface shrunk by nearly 25%, losing a significant portion of its carbon within the first two years of the 10 year period — especially when covered with the litter of decomposing tree leaves.

There are many solutions for this.

First, we need to understand that charcoal is active, especially in oxygen-rich atmospheres, and, when caught in fire, burns really fast, releasing CO2. Most people have used charcoal in barbeques and some people know that charcoal is often used for smelting in foundries, as it can reach very high temperatures.

A simple solution to prevent decomposition would be like with any other fuel: to remove oxygen and microbes from the equation. So, if we would, for instance, bury charcoal and cover it with clay, not allowing it to breathe, charcoal would decompose at a much slower rate.

It would be helpful if we would use techniques that would make the carbonisation process much more efficient. There are different techniques that can be used to carbonise biomaterial: hydrothermal carbonisation, catalytic carbonisation, slow pyrolysis, etc. Each method has different pros and cons, but, recently, microwaves have found their usage with significant success locking in more carbon than is usually achieved by slow-burning pyrolysis.

Also, it is worth mentioning that, depending on pressure, air content (oxygen, vacuum, inert gas), and temperature, carbon from biomaterial will be carbonised in different allotropic forms. Instead of charcoal, just by using different temperatures and pressures, it is possible to convert bio material into graphite and graphene and, in some cases, even in nano tubes that are quite stable and do not react with oxygen and, in addition, have multiple other commercial uses.

Graphite has a huge number of other possible uses outside of the normal use in pencils and brushes for electric motors.

Each of the methods used will require certain amounts of energy to convert raw biomaterial into the desired form; if we use the Sun, methane, or wind energy in the process, the price of carbonisation could be decreased significantly. Again, usage of any of the above-mentioned products for commercial purposes would dramatically decrease the overall cost of this “leaves carbon sequestration schema”, providing cost-effective alternatives against other geoengineering techniques.

Now, at this point, we have to consider that large amounts of charcoal are already made on a daily basis, and, instead of leaves, we use wood (cutting down forests, in order to create it).
Switching to using leaves should prevent future deforestation for that purpose, and it would sequester the mentioned amounts of CO2. Using this method would just mean a change of industrial behaviour. Instead of using one material that is scarce and needs a long time to grow (trees), they would switch to another (leaves) that is abundant, rarely used, and is a byproduct of seasonal change.

Level 3: Making activated carbon and batteries

Activated carbon is nothing but a further step in the process; basically, it is charcoal processed in such a way it would have small pores that increase the surface area available for absorption or chemical reactions.

The process of activation gives many more uses than charcoal would otherwise have: medical uses, spill cleanup, groundwater remediation, drinking water filtration, air purification, fuel storage, and many others.

But, the most important usage we would like to consider is usage in super-capacitor batteries, due to increased surface of carbon flakes because of activation, which gives it a higher W/kg energy storage ratio.

The battery storage, due to a long cycle life, would lock carbon inside super-caps for a very long time.

Typical Li-Ion residential energy storage currently has a typical life of 1500-2000 cycles; if we divide that by 365 days in a year, taking one charge every day, we could approximate a life of 5 years.

All-carbon batteries have a life that is measured typically in 100,000 cycles (100 thousand); charging them once a day would give it a life of more than 250 years (if we survive, by then I hope civilisation will have those fusion reactors). There is also one other aspect of super-caps: they charge in seconds to minutes, unlike Li-Ion that needs hours.

Why is that important?

Although I am envisioning all carbon batteries predominantly for residential usage, as they have poor energy to weight storage ratio in comparison to Li-Ion batteries, their fast charging ability still makes them viable for usage in vehicles like trains, trams, buses, and even cars.

A Tesla car with an 85kW battery currently needs about one hour to charge the battery to full, giving it range of 272 miles (438 km). Super-cap batteries can recharge in 5 min, but we will approximate that it has 3 times shorter of a range than Li-Ion battery packs, so 90 miles (144km). To travel the same distance, the driver would charge the super capacitor only for 15 minutes, but he would need to stop more frequently.
Now, you could say that it could be quite cumbersome to stop every 90 miles, especially for very long trips. Instead, if each stop sign would have a charging station, every time a driver stops at a red light, it would charge his car. But, what if we could charge while driving? There is an Israely company already working on that idea.

Continuous charging would be an absolutely viable solution for any vehicles that already have rails, and most rails already have that facility. It would be viable even if we would charge vehicles only in segments or just when they are waiting to pick up passengers at stations.

All-carbon batteries have already been developed; what the scientific community is currently working on is to try to perfect the technology even more, trying out different configurations. Depending on the chemistry used, this type of battery can be absolutely harmless and could even act as a fire retardant, unlike Li-Ion batteries that can catch on fire or, in some cases, even explode.

If super-caps end up in landfills, they will behave as charcoal, helping plants to grow.

Currently, activated carbon is obtained from cutting wood and graphite, which is obtained by mining. Instead, in order to “kill two birds with one stone”, I am proposing switching to leaves, as it would prevent decomposition and CO2 emission back into the atmosphere, and, additionally, it would lock carbon in electricity storages.

Additionally, wide usage of residential energy storage will reduce the need for gas and coal power plants (running on idle, wasting huge amounts of energy: currently, rejected energy is 60%, which means that we needlessly emit 6 out of 10 molecules of carbon. If we could optimise that and just reduce waste to 0, instead of 9.795 GtC [giga tonnes of carbon], we would emit only 3.918 GtC per annum).

It is important to understand that current Li-Ion batteries also need significant amounts of activated carbon, and it is quite possible that this could be obtained from leaves.

All-carbon batteries for personal gain

Let’s imagine you are the type of human being that does not care about some coal power plant running on idle, needlessly producing CO2, and that, at this point, you do not feel in danger, like Puerto Rico’s citizens—not being bothered by the idea that, in a few years, something similar could happen to you. And that is ok; we will put all that aside and we will imagine you are type that asks the question, “What do I get out of it?”

So, what do I personally get out of it?
Currently, in the United Kingdom, in a majority of households, there is a 2 tariff electricity system. During the day hours, the electricity cost is around £0.16 ($0.22), and, during night hours, that price is around £0.06 ($0.08). Currently, the US average electricity consumption is 11,700 kWh each year, and, in the UK, 4,600 kWh. Respectively, they will spend (having in mind UK prices) $2574 and $1012 if they use mostly electricity charged at the higher tariff, and usually everyone does.

If you had an energy storage like the 14kW Tesla power wall, costing $5900, in the UK, it would save you $644 ($1012-$368), paying for itself after 9 years, without any solar system, and then continue perpetually saving that amount of money for you. Please have in mind that, if you were in the UK, consuming so much electricity, probably, you would not take a power wall that is that powerful.
In America, on the other hand, it is a much different story: you would save $1630 ($2574 - $944 (11700*0.08)) a year, paying off your power wall after only ~3.6 years, afterwards continuing to save that amount of money for a lifetime. As all-carbon super-cap batteries have 100,000 (100 thousands) cycles per life, the battery storage would last for 273 years (100K / 365 (one charge each day)). Probably, many other things will fail before that happens.

What other benefits are there to having your own energy storage?

When the grid fails and lights are out, you can still have energy for some time (depending on when was the last charge). The storage would signal the grid power failure, giving you a choice to reduce electricity consumption, leaving turned on only what is needed the most. Turning off water heaters, washing machines, dish washers, and the oven could give you at least a few days of backup for the fridge, necessary lights, TV, radio, and other crucial appliances.

How much carbon is needed for batteries?

In a previous article, we approximated that 14 kW of energy storage has approximately 1170 cells, and, in the case of super-caps, we would need 3 times that, or around 35 kg of carbon.

If we take into account that converting 1 kg of dry biomass (leaves) only returns 30% (low estimate) of carbon, that would mean 300 g of charcoal.

There are around 7.5 billion people in the world, with an average household of 4 people. To satisfy the planet’s needs for residential energy storage, we would need 65.6 billion kg.
As we aim to sequester 5GtC or 5,000,000,000 tons (1000 kg) of carbon each year, just after the first year, we would have more than enough for all the batteries in the world.

So, what do to with all that remaining carbon? First, we would need extra batteries for the grid and industry, but still we could satisfy all that after one year. Remaining carbon can be used for carbon fibres to create stronger concrete blocks, to reinforce polymers, to filter polluted rivers and air...
It could be used for a range of electronics and potentially further converted into graphene, were we could use it for lighting, solar energy, energy transmission, heat transfer, space industry, and many other uses.

Why “attacking” nature’s carbon?

It is illusory to believe that people will change their habits overnight, becoming compassionate and considerate about the planet. Maybe, some people will reduce meat consumption, maybe a small percent will start to recycle, but, in the grand scheme of things, that is a negligibly small effort. The same people who make all those efforts will continue driving cars or using intercontinental flights, nullifying the positive effects and efforts to reduce their CO2 footprint.

So, from that perspective, all those behavioural climate change efforts and funds are just one big needless waste of money. Yes, it is good to raise awareness, but, at some point, there is not much you can do about global population behaviour. Simply put, people as a sum do not change their habits that easily, because the system has already trained them to have those habits and encourages them on daily basis to continue with those consumer habits.

Have in mind that this “leaves collection method” is just a transition method; it is obvious that we are still moving very slowly and that electric car production has not moved significantly, as of yet. Also, artificial meat production has not caught on. Therefore, this is just a temporary measure, which should help all those technologies to pick up speed and make the transition easier.

Because of all that, the entire idea is to create an imbalance between sequestering and emission. Currently, land mass is sequestering 60GtC per year, but also it emits the same amount, because of decomposition, back to the atmosphere. The idea is to allow nature to continue pulling the same amount of 60 GtC but to prevent emission by lowering released CO2 by at least 5GtC. That can be done if we starve part of the microbes and fungi for a short period of time.

Some people say that carbon is good for nature, and that increased amounts will make green things grow larger, but that is only partially true. Millions of years ago, plants ruled the planet, but, now, most of the plants (trees and shrubs) are cut down, creating naked land for agricultural purposes, slowly degrading top soil.

This time, there are too many people addicted to fossil fuels, and consumerism is causing the extinction of other species in the process. There aren’t enough plants anymore to handle the increased CO2.

At the present time, oceans are already failing, and some scientists say they could fail completely, losing the ability to pull in more CO2, thus releasing toxic gases back to the atmosphere, so, whatever we decide to do, we have to do it very fast.


1. This is a temporary schema. That means it should be used just for a limited amount of time, until we get to the point that we are using all clean energy sources that do not emit CO2. Running this for a very long time could damage the biosphere and topsoil even more.
2. This method must be used in conjunction with switching to 100% clean energy %, drastically cutting meat consumption (e.g. switching to artificial meat) and stabilising / possibly reducing human population numbers (reducing poverty, empowering women...).

A worse scenario would be the usage of Level 1, piling huge amounts of briquettes without storing them properly, while continuing population growth, continuing to deplete fossil fuels, all while continuing to consume meat. At one point, a huge pile of leaves would start decomposing; this, combined with CO2 emission from continual consumption of meat and fossil fuels, would mean instant death for everyone and everything on this planet.

A few ideas, instead of a conclusion

At the end, I will just hint at two more ideas for the next time:

1. To reduce further charcoal CO2 emission and allow for faster recovery of areas affected by wildfires, burned forests should be managed in certain ways, performing road construction and reforestation.
Collecting charcoal left from millions of acres of burned woods is already one step away from activated carbon.
Processing it further and keeping it dry (away from microbes), so it would not release CO2, would be hugely beneficial.

2. There is between 1.3 and 1.5 billion cattle in the world; one cow produces about 250 litters of methane each day. All cattle together produce a significant amount of methane (a greenhouse gas 25-75 times more dangerous than CO2). That methane can be used to convert leaves into charcoal at a very low price.

Lastly, as people express their wishes to see this happen, in order to speed things up, I would appreciate your help. There are multiple ways you can help, but, for now, just sending an email to grisanik[AT] with your name and a bit about yourself would suffice.
Soon, I will write more about the ways you could help.