Biochar: How burning stubble could FIGHT air pollution

Summary

Biochar, a product of pyrolysis where organic materials are burned in low-oxygen conditions, is touted as a multifaceted solution to air pollution, energy generation, and carbon sequestration. It locks carbon into the soil for centuries, potentially reducing CO2 emissions. However, critics warn of its potential to drive land conversion and logging, mirroring past biofuel controversies. Despite these concerns, biochar's ability to enhance soil quality and reduce greenhouse gases, particularly when using waste biomass, positions it as a promising tool in the fight against climate change.

Takeaways

• 🔥 Biochar is a product of burning organic material like wood at high temperatures (700-800 degrees) in an oxygen-limited environment, known as pyrolysis.
• ♻️ The process of making biochar generates combustible gases and bio-oil, which can be used for energy production, while the remaining biochar locks in carbon.
• 🌿 Biochar has the potential to sequester up to 80% of the carbon contained in the original biomass, making it a promising tool for carbon capture and storage.
• 🌱 When added to soil, biochar can improve soil quality, increase water retention, and enhance crop yields, especially in nutrient-poor or sandy soils.
• 🌳 The use of biochar can reduce the release of nitrous oxide, a potent greenhouse gas, by up to 80% when used in conjunction with fertilizers.
• 🌍 Critics argue that large-scale biochar production could lead to increased land conversion and deforestation, with negative impacts on ecosystems and biodiversity.
• 🌾 There is a significant opportunity to utilize agricultural waste, such as rice husks, to produce biochar, which could help mitigate air pollution and climate change.
• 💡 Biochar can be used in innovative ways, such as in concrete production, to reduce the carbon footprint of construction industries.
• 💰 The sale of carbon credits associated with biochar production is controversial, as it may not always reflect actual carbon sequestration and can be subject to market manipulation.
• 🌐 While biochar shows promise, it is not a silver bullet for climate change and should be considered as part of a broader suite of solutions that includes waste reduction and circular economy approaches.

Q & A

What is biochar and how is it produced?

Biochar is a stable carbon-rich material produced by heating organic materials, such as wood, in the absence of oxygen at temperatures of 700 to 800 degrees Celsius, a process known as pyrolysis. This process results in the evaporation of substances within the biomass, leaving behind pure, stable carbon.

How does biochar help in carbon sequestration?

Biochar can lock up to 80% of the carbon contained in the original biomass for hundreds of years by preventing it from decomposing or burning and releasing CO2 back into the atmosphere. This carbon sequestration helps in reducing the amount of carbon dioxide in the atmosphere.

What are the potential environmental impacts of biochar production mentioned in the script?

The script discusses concerns that increased demand for biomass for biochar production could lead to more land conversion, deforestation, and negative impacts on nature and biodiversity, similar to the issues faced with biofuels.

How can biochar be used to mitigate air pollution and climate change according to the script?

The script suggests that by converting agricultural waste like rice husks into biochar, significant amounts of CO2 emissions can be reduced, contributing to the mitigation of climate change. Additionally, the combustible gases produced during pyrolysis can be used to generate energy, further reducing reliance on fossil fuels.

What is the role of biochar in enhancing soil quality and crop yields?

Biochar can improve soil quality by increasing water and nutrient retention, especially in nutrient-poor and sandy soils. It provides a large surface area that supports beneficial fungi, bacteria, and microbes, which are essential for plant health, and can also reduce the emissions of nitrous oxide, a potent greenhouse gas.

What is the controversy surrounding the use of biochar in agriculture?

While biochar can enhance soil quality and increase yields, critics argue that its effectiveness is inconsistent and unpredictable. There are also concerns about the potential negative impacts on soil health in some cases, and the overall sustainability of biochar production if it leads to deforestation or increased land use for dedicated biomass crops.

How does the script address the issue of biochar production using waste biomass?

The script highlights the potential of using waste biomass, such as agricultural residues, to produce biochar, which could be a more sustainable approach than clearing forests or converting land for dedicated biomass crops. This approach aligns with circular economy principles.

What are the different ways biochar can be utilized according to the script?

The script mentions several uses for biochar, including as a soil amendment to increase yields, in concrete to reduce the carbon footprint of construction, and as a means to generate energy through the use of combustible gases produced during pyrolysis.

What is the significance of the carbon credits mentioned in the script in relation to biochar?

The script discusses the concept of carbon credits, which can be issued when biochar is used to store carbon in the soil. This can provide a financial incentive for companies to produce and use biochar, but the script also notes that the system of carbon credits is controversial and requires careful consideration.

How does the script evaluate the potential of biochar as a climate change mitigation tool?

The script presents biochar as a promising technology with the potential to address multiple environmental challenges, including soil enrichment, yield increase, CO2 and nitrous oxide reduction, and reduced fertilizer and water use. However, it also emphasizes the need for caution and proper management to ensure that biochar production does not contribute to deforestation or other negative environmental impacts.

Outlines

00:00

🔥 Biochar: The Controversial Carbon Capture Method

Biochar, a product of burning organic materials like wood in low-oxygen conditions (pyrolysis), is touted as a solution for air pollution, energy generation, and carbon dioxide reduction. The process leaves behind pure carbon, which can sequester carbon for centuries. However, critics argue that the method could lead to increased demand for biomass, potentially causing deforestation and harming biodiversity. The video visits a biochar plant, NovoCarbo, which aims to optimize its systems for full operation by 2024. Despite the potential environmental benefits, concerns arise regarding land conversion for biomass production and the historical pitfalls of biofuels.

05:01

🌱 Biochar's Potential in Agriculture and Energy

Biochar's application in agriculture is highlighted, with its ability to enhance soil quality and increase crop yields, especially in nutrient-poor and sandy soils. The video discusses the possibility of using biochar in mobile units to convert agricultural waste into a valuable resource, potentially reducing greenhouse gas emissions. Companies are exploring various uses for biochar, including heating greenhouses and producing carbon-negative energy. The effectiveness of biochar varies, with some studies showing increased yields and others indicating inconsistent results. Biochar's high surface area makes it an excellent medium for beneficial microbes and can help retain nutrients and water, reducing the need for fertilizers and improving water retention in soils.

10:04

🌿 The Promise and Pitfalls of Biochar Carbon Credits

The video concludes with a discussion on the controversial aspect of biochar: carbon credits. By sequestering carbon in the soil, biochar can potentially generate carbon credits, which companies like NovoCarbo can sell. However, the carbon credit system itself is a point of debate. Biochar's potential to reduce CO2 and nitrous oxide emissions, as well as its use in improving soil health and reducing the need for fertilizers, is recognized. Yet, the video cautions against viewing biochar as a one-size-fits-all solution to climate change, emphasizing the importance of using locally available waste biomass and considering the broader implications of its production and use.

Keywords

💡Biochar

Biochar is a form of charcoal made from biomass that has been heated in the absence of oxygen, a process known as pyrolysis. It is considered a potential tool for carbon sequestration, as it can lock carbon into the soil for hundreds of years. In the video, biochar is presented as a means to combat air pollution, generate energy, and reduce atmospheric carbon dioxide. The script discusses how biochar can be produced from waste biomass and how it can be used to enhance soil quality and increase agricultural yields.

💡Pyrolysis

Pyrolysis is the thermal decomposition of organic material at high temperatures in the absence of oxygen. This process is central to the production of biochar, as it transforms wood or other organic materials into a stable, carbon-rich form. The video explains that during pyrolysis, the substances inside the biomass evaporate, leaving behind pure, stable carbon that can be used as biochar.

💡Carbon Sequestration

Carbon sequestration refers to the long-term capture and storage of carbon dioxide to mitigate climate change. The video discusses biochar's potential as a carbon sequestration tool, highlighting that it can lock carbon into the soil, preventing it from being released back into the atmosphere as would occur with decomposition or burning.

💡Greenwashing

Greenwashing is the practice of making an unsubstantiated or misleading claim about the environmental benefits of a product, service, or company. The script mentions that some critics view the hype around biochar as a form of greenwashing, suggesting that its benefits may be exaggerated or oversimplified.

💡Carbon Credits

Carbon credits are a form of tradeable certificate that represent the right to emit a certain amount of carbon dioxide or the equivalent amount of another greenhouse gas. The video touches on the concept of carbon credits in relation to biochar, explaining that storing carbon in the soil through biochar production can potentially generate carbon credits.

💡Biomass

Biomass refers to organic material that can be used as a source of energy, such as wood, agricultural waste, or other plant matter. The video emphasizes the use of biomass in the production of biochar, noting that it can be sourced from waste materials like rice husks or other agricultural residues.

💡Nitrous Oxide

Nitrous oxide is a potent greenhouse gas with a global warming potential significantly higher than that of carbon dioxide. The script discusses how biochar can help reduce nitrous oxide emissions by improving the efficiency of fertilizer use in agriculture, thus mitigating its contribution to climate change.

💡Soil Amendment

A soil amendment is a material added to soil to improve its physical, chemical, or biological properties. Biochar is mentioned in the video as a soil amendment that can enhance soil quality by increasing water and nutrient retention, as well as providing a habitat for beneficial microbes.

💡Circular Economy

A circular economy is an economic system aimed at minimizing waste and making the most of resources. The video suggests that biochar production can be part of a circular economy approach by utilizing waste biomass that would otherwise be discarded or burned.

💡Climate Crisis

The climate crisis refers to the ongoing long-term changes in the Earth's climate system, primarily due to human activities. The video discusses biochar as a potential tool for mitigating the climate crisis by reducing greenhouse gas emissions and enhancing soil health.

💡Yield

In agriculture, yield refers to the amount of crop produced per unit area. The script highlights that biochar can increase yields, particularly in nutrient-poor or sandy soils, by improving water and nutrient retention, which is crucial for sustainable agriculture.

Highlights

Biochar is a form of burnt wood that can combat air pollution, generate energy, and reduce atmospheric carbon dioxide.

Biochar is produced through a process called pyrolysis, where organic material is burned in the absence of oxygen at high temperatures.

Pyrolysis results in combustible gases and bio-oil, which can be harnessed for energy production, leaving behind pure, stable carbon.

Biochar can lock up to half of the carbon from biomass into the soil for hundreds of years, preventing its release back into the atmosphere.

NovoCarbo, a company planning to be operational by 2024, is optimizing systems to produce biochar and utilize all byproducts.

Biochar production has been a part of human activity for thousands of years, with various methods such as mound and clamp kilns.

The key to biochar production is excluding oxygen to prevent complete combustion and maximize carbon capture.

Biochar can sequester up to 80% of the carbon contained in the original biomass, depending on the pyrolysis process.

Critics argue that biochar production could lead to increased land conversion and deforestation, harming ecosystems.

Biochar has the potential to mitigate climate change by reducing CO2 emissions, as demonstrated by its application in India with agricultural waste.

In India, converting agricultural waste to biochar could reduce approximately 10-13% of the country's total greenhouse gas emissions.

Biochar can be used to improve soil quality and increase crop yields, particularly in nutrient-poor and sandy soils.

Biochar's high surface area makes it an excellent medium for beneficial soil microbes and for retaining nutrients and water.

Use of biochar in soil can reduce nitrous oxide emissions, a potent greenhouse gas, by an average of 40-80%.

NovoCarbo sells biochar primarily to horticulture companies for soil amendment, enhancing its carbon sequestration potential.

Biochar's effectiveness varies and is not universally beneficial, with impacts ranging from negative to positive depending on soil conditions.

Biochar's potential as a climate solution is contingent on the availability of local, wasted biomass and circular economy approaches.

Transcripts

This unassuming bit of burnt wood

is supposed to help fight air pollution,

generate energy

and reduce carbon dioxide in the atmosphere.

And It's called biochar.

Sounds incredible, doesn't it?

Well, some say the hype around this char

is just greenwashing.

What is it about biochar that makes it so controversial?

We came to a biochar plant to get some answers.

This is a brand-new biochar plant.

And it produces much more than that.

And we'll come to that in a second.

Biochar is wood

or any other organic material

that is burned up to 700 or 800 degrees

in the absence of oxygen.

And that is called pyrolysis.

The heat evaporates the substances inside the biomass.

They are emitted as combustible gases and bio-oil,

which can be used to generate energy.

And what we are left with at the end of the process

is pure, stable carbon.

Once the biomass starts burning,

most systems can sustain themselves

without using additional energy.

As part of the planet's carbon cycle,

plants absorb CO2 from the atmosphere

and grow as biomass.

But when they die,

they decompose

and most of the CO2 they sucked up

is released back into the atmosphere.

But instead of decomposing or burning,

if we turned them into biochar,

we could lock half of their carbon into the soil

or elsewhere for hundreds of years.

"The people are more and more aware of that.

We need to store more and more carbon."

This is Casper Ziegner, the CEO of NovoCarbo.

They are planning to be fully operational

by the first quarter of 2024.

Until then, they are optimizing their systems.

The experiments with different uses of biochar

kicked off over the last decade.

But actually, from mound kilns to clamp kilns,

we have produced charcoal in many ways

for thousands of years.

There are many ways of making biochar,

but not many of them look like a spaceship.

The key is to keep oxygen out.

If we can't,

the biomass will continue to burn,

turning to ash,

and most of the carbon inside

will go back into the atmosphere,

which is exactly what we want to avoid.

But here the process is much more complex.

Because this plant, while producing biochar,  

it makes sure that it uses all the combustible gases

feeds them back into the system,

keeps the temperatures high

and this way captures as much carbon as possible.

Depending on the biomass and the pyrolysis process,

up to 80% of the carbon it contains

can be sequestered.

That is why biochar is now being presented by the industry

as a good way to store carbon dioxide.

But not everyone is cheering.

"Going down that route in the name of carbon sequestration

and carbon negative emissions,

will create a huge new demand for biomass."

Almuth Ernsting

and her team at British NGO Biofuel Watch

have been following the debate

and scientific data on biochar since 2008.

"It would inevitably mean more land conversion

to growing dedicated crops

and/or more logging of forests,

both of which would have really devastating impacts

on nature."

And sadly, we have already seen that happen elsewhere.

Biofuels were once hailed as an ecofriendly source of energy,

produced mainly from corn or sugarcane.

But many experts say biofuels can often do

more harm than good

because of the way we grow them.

Critics worry that we could be making the same mistake

again with biochar.

Deforest an area,

plant fast-growing biomass,

chop it down

and turn it into biochar,

destroying ecosystems

and biodiversity in the process.

But we don't have to.

Because there is a huge amount of biomass

we are currently wasting.  

"Stubble burning"

"Stubble burning"

"Stubble burning"

"Stubble burning in Northern India..."

According to a recent study,

in India alone, 120 million tons of rice husks

and other agricultural waste

are burned in open pits every year.

And this contributes significantly to air pollution

around the country,

which kills up to two million people per year.

According to Prof. Priyanka Kaushal biochar can help.

"So if we convert these 120 million tons

that we see into biochar,

we see about roughly 350 million tonnes

of CO2 emission production

if that is converted into [biochar].

which is about roughly about 10 to 13%

of the total GHG emission that India does."

That would be a huge contribution

to mitigating the climate crisis!

India is currently the third highest CO2 emitter in the world.

And the farmers producing the biochar

could use it to increase their yields

or sell it for extra income.

"What we are proposing

is to have a mobile unit, small units."

That can produce biochar in the field itself.

Maybe not in every field,

but maybe every district has a centralized location

where you can produce.

You can bring your regular residues there,

convert it into char.

We could replicate this in many other places in the world.

Estimates of how much biochar can reduce

climate-warming gases without harming ecosystems vary.

But it is a technology that has the potential

to address many environmental challenges at once.

The difference between this huge pyrolysis plant

and the smaller ones

is what you can do with the excess energy,

here they heat up water and sell it to the grid.

And this is a very convenient and eco-friendly way

of heating homes.

Other companies like this one in Australia

use excess energy to heat their greenhouses,

and use the biochar for growing plants.

Some people call it carbon negative energy,

as at the end of the process

we will have carbon locked in biochar.

If it is produced with excess local biomass,

it could make it a great way of producing energy.

But ultimately it depends on how we get the biomass,

and what we do with it.

If it was transported from hundreds of kilometers away,

or if the forests had to be cleared.

Or if it is used to replace coal burning,

then it is no longer eco-friendly.

NovoCarbo may sell hot water to the city,

but its main product goes to farmers!

"We mainly sell to horticulture companies,

mainly to Scandinavia at the moment."

More and more agricultural businesses use biochar

to enhance soil quality and increase yields.

"We see that in poor soils

it seems to work better than in very rich soils

and also if you have sandy soils,

you improve the water holding capacity usually."

This is Claudia Kamann.

She has been researching biochar for the last 15 years.

"After more than a decade of biochar research

we know from meta studies

which compile a lot of knowledge

from different scientific studies

that we have on average increases in yields."

But critics say that these "average" biochar results

hide inconsistencies,

and in some cases actually cause harm.

"Impacts on soil can be negative,

can be neutral,

can in some cases be positive,

and nobody can predict

how it will play out at any one time."

Many scientists say they do not fully understand

why biochar does what it does,

but they can measure the results.

In many cases, these are positive,

but scientists struggle to create conditions

where biochar's effects are 100% predictable.

"The critics are not totally incorrect.

It's not a black fairy powder

that works the same kind of miracle everywhere,

but you can normally extract cases

where it works quite well."

And these cases are widely known.

Biochar works wonders in the nutrient-poor soils

of the tropics.

That is because biochar has an incredible surface area.

This will sound crazy:

but one gram of high-quality biochar

can have more surface area than a basketball court.

This makes biochar an amazing host

for all the fungi, bacteria and microbes

that are essential for plant health.

It can also retain the nutrients,

making them available for the plant.

The same goes for water

because biochar can store up to 5 times its own weight.

That is why biochar can help increase yields,

particularly in sandy soils,

that otherwise easily lose water and nutrients.

And...

it also has other surprising effects.

"Nitrous oxide is a very powerful greenhouse gas

that has on average more than

280 times of warming potential

than CO2 has over 100 years.

And nitrous oxide is mostly formed

from the huge amount of fertilizers that we use."

Bacteria in the soil

can break down nitrate-based ammonium fertilisers into N2,

which is not a greenhouse gas.

But we put so much fertiliser on the land

that the microbes can't process it all,

and it goes into the atmosphere

as the climate-killer nitrous oxide.

Up to 75% of the world's nitrous oxide emissions

come from agricultural activities.

"Several meta studies now exist

to show that on average we have a reduction of about 40%

of these nitrate emissions

if you use biochar in soils together with fertilizers.

But in some of the production studies

we did at Geisenham University

we've seen reductions of up to 80%."

A 40 to 80% reduction in this climate killing gas!

That is really promising!

Back on the Baltic coast,

NovoCarbo is looking for a return

on their considerable investment of 8.5 million euros.

That's why they are also selling another product

that is somewhat controversial.

"Producing the biochar, our core product,

we bring this biochar into applications,

for example into soil, a soil amendment

Once having brought the biochar into the soil,

a carbon credit can be issued

because we have stored the carbon,

the biochar, permanently in the soil

and then it's fixed there.

We produce at this site

roughly 1700 tons of biochar per year

and this means roughly 3200 tons of CO2."

That is equivalent to

around what 400 Germans emit on average in a year.

It's not much, but it's a start.

The system of buying carbon credits

to balance out emissions can be controversial,

and we spent a whole episode digging into that.

Definitely check it out

if you want to go down the rabbit hole.

But carbon credits aside,

biochar looks like a very promising way

of tackling many of the climate-related problems

we face today:

From enriching the soil and increasing yields

to reducing CO2 and nitrous oxide in the atmosphere.

It can help us use less fertilizer and water.

We didn't even mention other potential uses of biochar

like in concrete

that could reduce the carbon footprint of construction.

BUT Biochar comes with a big caution:

It's only useful if we have a lot of

otherwise wasted local biomass.

"That's why we focus on waste streams and looking into

all these circular economy approaches we have.

There will be much more

biomass available in the in the future.

But presenting it as a massively scalable global solution

to all our climate problems

is just another way of trying to come up with simple solutions

to our complex problems.

What do you think about biochar?

Could it be a good tool to mitigate the climate crisis?

Would you start using it?

Let us know in the comments.

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