Make Your Own BioChar and Terra Preta

Introduction: Make Your Own BioChar and Terra Preta

A simple way to make BioChar in a 55 gallon drum. Hoping to promote simple, scalable, environmentally sound methods for making biochar for improving the soil on small farms and in backyard gardens. And improving the air as well.

When you bury the carbon you are sequestering it out of the atmosphere for hundreds of years. A pound of carbon buried this way takes quite a bit of CO2 gas out of what's overhead.

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Step 1: Overview

Cartoon of the process. I would like to sketch some more designs and have people test them.

Step 2: Prep & Materials

55 Gallon Drum, with Lid
Drum sealing ring
Dry Biomass - usually wood & wood chips, or dung

Hoe, rake, shovel
Dust mask, ear protection, eye protection
Heavy gloves, boots
Hose & nozzle
Metal cutting circ saw or hammer & chisel

Step 3: Make the Charcoal

Seal up the lid and roll the drum onto the fire. You want the vent holes pointing down into the fire so that methane gases get flared off before they escape into the atmosphere, causing atmos damage.
The drum has to sit on the fire for several hours. First steam comes out for 2 to 4 hours, as the water boils off. Then, volatile gases (VOC's) such as methane and hydrogen start blazing out of the slots like blowtorches, for 1 to 2 hours. When the gases have all flared off, there will be little or no smoke. The carbon will start to burn, sucking oxygen into the barrel. That's when you want to stop the process by rolling the drum off the fire and covering the slots with sand to starve the oxygen. Water helps too, since you're happy with wet charcoal.

Step 4: Remove From Fire and Cool

Watch out for hot ground, hot sand!

Step 5: Making Biochar Into Terra Preta

Crush the charcoal with your grape smashers (boots). Add fungal wood chips, household compost, (especially milk, fish, and bones) leafy compost, chicken gickem, urine, grey water, worm tea, fish tank water, you name it! Try to get the charcoal juiced up with calcium, nitrogen, bacteria and fungus before you put it into your garden. Enjoy it for hundreds of years! The ancients added pottery shards, which may absorb toxins, but I like to use my hands in the soil, so I don't add that. Do add crushed clamshells and eggshells.

You just sequestered some carbon!

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Find out everything - International Biochar Initiative,
Hat Tip to Gunther Folke & his retort method:
Join the Biochar group here at
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25 Discussions


10 years ago on Step 5

 This is very helpful!  Thanks for making this Instructable.  

However, please note that THIS method of charcoal production is NOT climate-friendly.  Any combustion process that releases un-burned gases will actually exacerbate the greenhouse-effect.  The simple pyrolysis/gasification effect created in this steel drum will release gases called "volatile organic compounds" or VOCs, including methane.  This looks like smoke or fumes, and may be gray or yellowish in color.  

Methane is a gas that is 20 to 25 times more potent than CO2 in trapping heat in the atmosphere.  In other words, the effect of the gases you create while making biochar could exceed the carbon-capture benefit of biochar in soils. 

To fix this, you have two options: 
1) make certain that any gases you create (i.e., "smoke" or "fumes") are burned or flared, thus reducing the VOCs to CO and CO2 (less potent GHGs than methane).
2) even better, engineer a system to make use of these gases for thermal energy.  Waste-not-want-not!



Reply 4 months ago

Sugar plum, honey bunch, we are entering a grand solar minimum and a mini-ice age. We have 90% crop failures in the USA and pretty much worldwide. The USDA, bless their little souls, are doing their best to sweep the problem under the rug because they can't find their heinies with both hands.
Red China has come out and said their scientists have come out and said northern China has had crop failures due to cold 7-8 years in a row. They said the ice age may last 250 years.
I sincerely hope they are wrong. At any rate, every human on earth needs to start growing their own food and teaching others how to do so.
As a biologist/biochemist I agree about toxic compound creation with you, but we do not have global warming. We have a natural earth cycle that is warm period followed by instability followed by ice age.
Geologic records show it was hotter when the dinosaurs were around and humans didn't exist.


Reply 9 years ago on Introduction

This is one of the least efficient method of making charcoal and does not even guarantee that you will have any bio-char when you finish. FYI Bio-char is characterized by the presents of cations on the carbon molecules and is created between the temp. of 700C and 800C in the presence of some water. I agree with you about the climate friendliness of this method. It could be if his production process offered more control and if the biomass was destined to rot or be burned anyway. Look for this on facebook it is a good working group for bio-char production in a responsible way.

Dear Sir,
I am a research dietitian/biologist/biochemist and Texas master gardener. I have been doing organic gardening since 1972, organic companion planting since 1973, and organic farming/ranching with my hubby since 1992.
I am using an Android type phone. Your sketches, text and photos cannot be enlarged on this website. In other words, I can't see a darn thing.
You need a website that is cell phone friendly.

Arthur Young
Arthur Young

Question 11 months ago

I always have pieces of charred wood when I clean out my wood heaters. Can I grind these into powder and use them as biochar? Do they have the same fertilize value?.


Question 1 year ago on Step 3

Thanks for sharing this. Is it possible to make the holes on the bottom of the barrel and burn it upright with the holes at the bottom? thanks.


9 years ago on Introduction

Correct wikipedia link is:


Reply 9 years ago on Introduction

Thank you for your link. I found it to be both accurate and encouraging. FYI the article on wiki about bio-char is not correct on a couple of important points namely it's def. of bio-char. Here a link to a good working group on Facebook.

I first meet the founders at an international symposium on bio-char in Richland, Washington. Later I attended their workshop in Seattle, Washington, where I learned to make T-LUD stoves that had been optimized for bio-char production.


9 years ago on Introduction

If you are burning a fire to make the biochar its releasing CO2. Does the amount of biochar you make offset this release? Would be good to figure out a simple way of capturing the syngas and re-using it to make biochar.


Reply 9 years ago on Introduction

Thanks fyc. The carbon that is collected as charcoal is highly recalcitrant - it doesn't evaporate to the atmosphere for many years, as it otherwise would if the wood was decomposing. So there is a net capture of CO2. The syngases are directed downward into the external fire and burned to help generate heat, so they are being used to make biochar. The efficiency of the system could be improved by building an external housing that would conserve heat from the external fire and direct it around the barrel, perhaps towards a cooking platform or water jacket, and up a high chimney, perhaps with an afterburner. I hope you can improve the design and participate in biochar online forums.

Update - I added llama poop and compost to the charcoal, let it stew for a couple of weeks an worked it into my soil last fall. This year my gardens seem really happy, my friends say my stuff is bigger and greener than theirs. That's as scientific as I got right now. It's a lot of work, & it's not super friendly to the atmosphere in this lo-tech method, so I'm not recommending it for everybody.


9 years ago on Step 1

This is very helpful!  Thanks for making this Instructable. 

However, please note that THIS method of charcoal production is NOT climate-friendly.  Any combustion process that releases un-burned gases will actually exacerbate the greenhouse-effect.  The simple pyrolysis/gasification effect created in this steel drum will release gases called "volatile organic compounds" or VOCs, including methane.  This looks like smoke or fumes, and may be gray or yellowish in color. 

Methane is a gas that is 20 to 25 times more potent than CO2 in trapping heat in the atmosphere.  In other words, the effect of the gases you create while making biochar could exceed the carbon-capture benefit of biochar in soils.

To fix this, you have two options:
1) make certain that any gases you create (i.e., "smoke" or "fumes") are burned or flared, thus reducing the VOCs to CO and CO2 (less potent GHGs than methane).
2) even better, engineer a system to make use of these gases for thermal energy.  Waste-not-want-not!



Reply 9 years ago on Introduction

Then you better put a cork in that ***** as sources of methane are not the best for smell... You wil find that all organic material that breaks down by bacteria (rotting) including the 75,000 people that pass away each day in the world, would fil a super jumbo jet hanger a day with methane... Let's be CONSTRUCTIVE, not, BUREACRATIC....


Reply 9 years ago on Introduction

 It looks like the author addressed the first option you mention in step 3.


9 years ago on Step 1

I had a similar idea, that I've not yet tried.  We have a great deal of waste sawdust available from a local sawmill. 

I'd thought of taking an open metal drum and building a roaring fire in it, then dumping sawdust in the drum until mostly filled, then capping it with soil. 

I think if the sawdust was dry, it would likely char.  

Maybe I'll get around to it this summer.


9 years ago on Step 2

Using a painted drum over a fire will give off some gases, and depending on the type of paint, could be toxic. Use a power drill with a wire brush attachment to clear any paint before heating


10 years ago on Step 5

I thought these update on developments of biochar soils may interest
you, I'm a biochar advocate, and would like to share my efforts in research, policy and industry.(bellow)

Biochar systems for Biofuels and soil carbon sequestration are so basically conservative in nature it is a shame that republicans have not seized it as a central environmental policy plank as the conservatives in Australia have.

Hope to see you at ISU for the 2010 US Biochar Conference

Dr. Robert Brown <>, andthe team in Ames Iowa are  planing  the next national biochar conference. The Conference will be June 27-30 in Ames Iowa Hosted by Iowa State University. The Call for papers;

The Biochar Fund  deserves your attention and support.
Exceptional results from biochar experiment in Cameroon

Mark my words;
Given the potential for Laurens Rademaker's programs to grow exponentially, only a short time lies between This man's  nomination for a Noble Prize.

He recently received the Manchester prize.

Thanks for your efforts.

Erich J. Knight
Eco Technologies Group Technical Adviser
Shenandoah Gardens (Owner)
1047 Dave Barry Rd.
McGaheysville, VA. 22840
540 289 9750
Co-Administrator, Biochar Data base & Discussion list  TP-REPP

Biochar Soils.....Husbandry of whole new orders & Kingdoms of life

Biotic Carbon, the carbon transformed by life, should never be combusted, oxidized and destroyed. It deserves more respect, reverence even, and understanding to use it back to the soil where 2/3 of excess atmospheric carbon originally came from.

We all know we are carbon-centered life, we seldom think about the complex web of recycled bio-carbon which is the true center of life. A cradle to cradle, mutually co-evolved biosphere reaching into every crack and crevice on Earth.

It's hard for most to revere microbes and fungus, but from our toes to our gums (onward), their balanced ecology is our health. The greater earth and soils are just as dependent, at much longer time scales. Our farming for over 10,000 years has been responsible for 2/3rds of our excess greenhouse gases. This soil carbon, converted to carbon dioxide, Methane & Nitrous oxide began a slow stable warming that now accelerates with burning of fossil fuel. Agriculture allowed our cultural accent and Agriculture will now prevent our descent.

Wise Land management; Organic farming and afforestation can build back our soil carbon,

Biochar allows the soil food web to build much more recalcitrant organic carbon, ( living biomass & Glomalins) in addition to the carbon in the biochar.

Biochar, the modern version of an ancient Amazonian agricultural practice called Terra Preta (black earth, TP), is gaining widespread credibility as a way to address world hunger, climate change, rural poverty, deforestation, and energy shortages… SIMULTANEOUSLY!
Modern Pyrolysis of biomass is a process for Carbon Negative Bio fuels, massive Carbon sequestration, 80%-90% Lower Methane & N2O soil emissions, and 2X Fertility Too.
Every 1 ton of Biomass yields 1/3 ton Charcoal for soil Sequestration (= to 1 Ton CO2e) + Bio-Gas & Bio-oil fuels = to 1MWh exported electricity, so is a totally virtuous, carbon negative energy cycle.

Biochar viewed as soil Infrastructure; The old saw;
"Feed the Soil Not the Plants" becomes;
"Feed, Cloth and House the Soil, utilities included !".
Free Carbon Condominiums with carboxyl group fats in the pantry and hydroxyl alcohol in the mini bar.
Build it and the Wee-Beasties will come.
Microbes like to sit down when they eat.
By setting this table we expand husbandry to whole new orders & Kingdoms of life.

This is what I try to get across to Farmers, as to how I feel about the act of returning carbon to the soil. An act of penitence and thankfulness for the civilization we have created. Farmers are the Soil Sink Bankers, once carbon has a price, they will be laughing all the way to it.
Unlike CCS which only reduces emissions, biochar systems draw down CO2 every energy cycle, closing a circle back to support the soil food web.  The photosynthetic  "capture" collectors are up and running, the "storage" sink is in operation just under our feet.  Pyrolysis conversion plants are the only infrastructure  we need to build out.

Senator Baucus is co-sponsoring  a bill along with Senator Tester (D-MT) called WE CHAR.  Water Efficiency via Carbon Harvesting and Restoration Act!  It focuses on promoting biochar technology to address invasive species and forest biomass.  It includes grants and loans for biochar market research and development, biochar characterization and environmental analyses.  It directs USDI and USDA to provide loan guarantees for biochar technologies and on-the-ground production with an emphasis on biomass from public lands.   And the USGS is to do biomas availability assessments. - S. 1713, The Water Efficiency via Carbon Harvesting and Restoration (WECHAR) Act of 2009

Individual and groups can show support for WECHAR by signing online at:

The Clean Energy Partnerships Act of 2009
 The bill is designed to ensure that any US domestic cap-and-trade bill provides maximum incentives and opportunities for the US agricultural and forestry sectors to provide high-quality offsets and GHG emissions reductions for credit or financial incentives. Carbon offsets play a critical role in keeping the costs of a cap-and-trade program low for society as well as for capped sectors and entities, while providing valuable emissions reductions and income generation opportunities for the agricultural sector. The bill specifically identifies biochar production and use as eligible for offset credits, and identifies biochar as a high priority for USDA R&D, with funding authorized by the bill.
To read the full text of the bill, go to:

Major Endorsements:

Senator / Secretary of Interior Ken Salazar has done the most to nurse this biofuels system in his Biochar provisions in the 07 & 08 farm bill,

NASA's Dr. James Hansen Global warming solutions paper places Biochar / Land management the central technology for carbon negative energy systems.

Dr. James Lovelock (Gaia hypothesis) says  Biochar is  "The only hope for mankind"

Charles Mann ("1491") in the Sept. National Geographic has a wonderful soils article which places Terra Preta / Biochar soils center stage.

Al Gore got the CO2 absorption thing wrong, ( at NABC Vilsack did same), but his focus on Soil Carbon is right on;

Tony Blair & Richard Branson in the UK and conservative party opposition leader  John Turnbull in Oz.


The Ozzie's for 5 years now in field studies
The future of biochar - Project Rainbow Bee Eater

The Japanese have been at it dacades:
Japan Biochar Association ;

UK Biochar Research Centre

 Virginia Tech is in their 4 th year with the Carbon Char Group's "CharGrow" formulated bagged product.  An idea whose time has come | Carbon Char Group
He said the 2008 trials at Virginia Tech showed a 46% increase in yield of tomato transplants grown with just 2 - 5 cups (2 - 5%) "CharGrow" per cubic foot of growing medium.

Dr. Rory Maguire,  

In  first year with Poultry litter char

USDA in their 2 nd year;  "Novak, Jeff" <>, &  "david laird" <>,
There are dozens soil researchers on the subject now at USDA-ARS.
and many studies at The up coming  ASA-CSSA-SSSA joint meeting;

Nikolaus has been at it 4 years. Nikolaus Foidl,
 His current work with aspirin is Amazing in Maize, 250% yield gains, 15 cobs per plant;

My 09 field trials with the Rodale Institute & JMU ;
Alterna Biocarbon and Cowboy Charcoal Virginia field trials '09

 Most recent studies out;

Imperial College test,
  This work in temperate soils gives data from which one can calculate savings on fertilizer use, which is expected to be ongoing with no additional soil amending.

BlueLeaf Inc./ Dynamotive study are exciting results given how far north the site is,and the low application rates. I suspect, as we saw with the Imperial College test, the yield benefits seem to decrease the cooler the climate.
The study showed infiltration rates for moisture are almost double. The lower leaf temperatures puzzles me however, I thought around 21C was optimum for photosynthesis.

BlueLeaf Inc. and Dynamotive Announce Biochar Test Results CQuest(TM) Biochar Enriched Plots Yield Crop Increase Ranging From Six to Seventeen Percent vs. Control Plots

The full study at Dynomotives site;


This PNAS report (by a Nobel lariat) should cause the Royal Society to rethink their report that criticized Biochar systems sequestration potential;
Proceedings of the National Academy of Sciences

Reducing abrupt climate change risk using
the Montreal Protocol and other regulatory
actions to complement cuts in CO2 emissions

United Nations Environment Programme, Climate Change Science Compendium 2009

  Congressional Research Service report (by analyst Kelsi Bracmort) is the best short summary I have seen so far - both technical and policy oriented. .

This is the single most comprehensive report to date, covering more of the Asian and Australian work;

Dr. Scherr's report includes biochar.

I think we will be seeing much greater media attention for land management & biochar as reports like her's come out linking the roll of agriculture and climate.

Biochar data base;

Disscusion Groups;
The group home page location, General orientation:
Biochar (
Biochar POLICY;
Biochar Soils;
Biochar Production;

Earth Science Terra Preta Forum, Great for students;
Terra Preta - Science Forums

Given the current "Crisis" atmosphere concerning energy, soil sustainability, food vs. Biofuels, and Climate Change what other subject addresses them all?

This is a Nano technology for the soil, a fractal vision of Life's relation to surface area that represents the most comprehensive, low cost, and productive approach to long term stewardship and sustainability.

Carbon to the Soil, the only ubiquitous and economic place to put it.

Erich J. Knight
Eco Technologies Group Technical Adviser
Shenandoah Gardens (Owner)
1047 Dave Barry Rd.
McGaheysville, VA. 22840
540 289 9750
Co-Administrator, Biochar Data base & Discussion list  TP-REPP

  The first North American Biochar Conference,  at CU  in Boulder ,
Keynote speakers were  Secretary Tom Vilsack & Dr. Susan Solomon (NOAA's head atmospheric scientist)

 My attendance is thanks to the folks at EcoTechnologies Group . ,  they have also fully funded my field trials with the Rodale Institute & JMU)

There is real magic coming out of the Asian Biochar conference.
15 ear per stalk corn with 250% yield increase,
Sacred Trees and chickens raised from near death
Multiple confirmations of 80% - 90% reduction of soil GHG emissions
The abstracts of the conference are at

Biochar Studies at the 08 ACS Huston meeting;

Most all this work corroborates char soil dynamics we have seen so far . The soil GHG emissions work showing increased CO2 , also speculates that this CO2 has to get through the hungry plants above before becoming a GHG.
The SOM, MYC& Microbes, N2O (soil structure), CH4 , nutrient holding , Nitrogen shock, humic compound conditioning, absorbing of herbicides all pretty much what we expected to hear.



665 - III.


Company News & EU Certification

Below is an important hurtle that 3R AGROCARBON has overcome in certification in the EU. Given that their standards are set much higher than even organic certification in the US, this work should smooth any bureaucratic hurtles we may face.

EU Permit Authority - 4 years tests
Subject: Fwd: [biochar] Re: GOOD NEWS: EU Permit Authority - 4 years tests successfully completed

Doses: 400 kg / ha – 1000 kg / ha at different horticultural cultivars

Plant height Increase 141 % versus control
Picking yield Increase 630 % versus control
Picking fruit Increase 650 % versus control
Total yield Increase 202 % versus control
Total piece of fruit Increase 171 % versus control
Fruit weight Increase 118 % versus control


Low Tech Clean Biochar;