How to Make Biochar

Climate change is a problem many people my age are concerned with.  We want to help the environment but it doesn’t feel like there is anything we can do.

 

After researching climate change solutions I discovered Biochar.  Biochar comes from slowly burning biomass.  What makes it great is that the char produced can capture carbon for more than 100 years or more and it turns out to be easy to make.

 

Unlike a regular fire where you want lots of oxygen, to make biochar you want very little oxygen.  In very rural locations some people make biochar by simply piling wood in a pit, lighting it on fire and then covering it up almost all the way.  

 

In my case I used 2 small metal garbage cans to make a simple kiln.   One has to be small enough to fit inside the other.  

The first step is to put 3-4 small screws in the bottom of the bigger can. These are to hold the smaller can up in the air so that what air there is can circulate evenly.

 

The next step is to put 6-10 small holes in the bottom of the small can to let air in.  I used a nail and just hit them through the bottom with a hammer.

 

The third step is to optionally take the top of the larger can and put a small chimney on it.  I decided to do this because I thought it would burn better.

 

That’s it.  The kiln is done.

 

To make biochar you fill the smaller can with any dry biomass.  I grew some sunflowers (because they are big and grow quickly) that I use  and  those with some dry twigs I found in the yard.  Put that in the smaller can, put the small can inside the big can and then light it on fire.  Once the fire catches, put the top on and let it burn for 2 or 3 hours.  If you want you can prop the top open a bit to let some air in. 

 

Because there is very little air the fire turns the biomass into something that looks kind of like charcoal.  You can bury this to capture the carbon.  A lot of people say this is very good to use in gardens.