I've been thinking of this idea for a while and I'm glad someone got around to actually designing and building it. No reason to build a fire to get biochar when we have power sources that can do it without using all that valuable wood that could instead be biochar. This way even prevents you from using grid power so you can be out in the woods and create your biochar on site!!
Many people can get their hands on used commercial or residential PV panels for cheap or free. The Living Energy Farm in VA (USA) has done tremendous work with direct DC power using repurposed PV panels, as one example. Low Tech Magazine also runs their whole website off of a few PV panels on an apartment balcony in Barcelona, Spain. Solar/PV and "renewables" can't power modern techno-industrial civilization, but there's lot's that "little guys" like us can do with PV panels and other detritus of modernism.
Josh, thanks so much for sharing this CC, you’re a legend.
Ok I’m really excited by this since the original kiln with the open flame really means the drums need replacing after about 5 years, and they’re a bit ridiculously priced here. I’ve been putting off my yearly batch of biochar (used for our composts/soil building) because my drums got so many holes now and very rusted.
I’m going to see if I can source the parts here but firstly I’m curious if you measured the power/current whilst the element was on? I’m gonna have to adapt this to our solar’s 220VAC.
Also, how do you know when the charcoal is done? How long does it generally take on a day of your good sun?
I’m thinking I might set up the chimney with a bend in order to collect wood vinegar (great for organic gardeners here).
Also I was gonna ask about what temperature you set it at, it looks like 500C from the graph (typo on the y-axis by the way but I forgive you as you’re American and working in your non-native units ;-)), I’ve managed to find most of these components but considering the source I’m buying it from (one of the Asian equivalents to a shittier than shitty Amazon) let’s keep fingers crossed that I a) don’t burn the garage down, b) don’t destroy my inverter, c) electrocute myself. Thanks once again Josh!
Also, I do apologise that I’m not using this yet for water filtration (I need something that will work on a pressurised system), but I’m sure you will agree that the use of biochar activated in compost is a great way for getting carbon back into the soil.
Sorry I am so slow to get back to you, Leon. I will try to answer a few things. One is that my observations have been that voltage output from my panels is pretty constant, even with indirect sun during time-of-day and low angle by season. But the amps are what vary. I bought a data-logging ammeter so I could track amps as these seem to be the sensitive factor for power output. Secondly, I have found that it's really important to have a good passage for the smoke to rise out of the system. If there are bends or occlusions in the chimney this could hind smoke egress and cause it to infiltrate inside the oven - where it causes all kinds of problems with the insulation and the wiring, etc. So at the moment I do not have a good answer for how to collect wood vinegar. I have been more focused on getting all the smoke associated chemicals out of the oven and burning them.
I've been thinking of this idea for a while and I'm glad someone got around to actually designing and building it. No reason to build a fire to get biochar when we have power sources that can do it without using all that valuable wood that could instead be biochar. This way even prevents you from using grid power so you can be out in the woods and create your biochar on site!!
Thanks for sharing!!
Thanks for the encouragement!
Great work!
Josh, who needs or can afford solar?
Many people can get their hands on used commercial or residential PV panels for cheap or free. The Living Energy Farm in VA (USA) has done tremendous work with direct DC power using repurposed PV panels, as one example. Low Tech Magazine also runs their whole website off of a few PV panels on an apartment balcony in Barcelona, Spain. Solar/PV and "renewables" can't power modern techno-industrial civilization, but there's lot's that "little guys" like us can do with PV panels and other detritus of modernism.
Josh, thanks so much for sharing this CC, you’re a legend.
Ok I’m really excited by this since the original kiln with the open flame really means the drums need replacing after about 5 years, and they’re a bit ridiculously priced here. I’ve been putting off my yearly batch of biochar (used for our composts/soil building) because my drums got so many holes now and very rusted.
I’m going to see if I can source the parts here but firstly I’m curious if you measured the power/current whilst the element was on? I’m gonna have to adapt this to our solar’s 220VAC.
Also, how do you know when the charcoal is done? How long does it generally take on a day of your good sun?
I’m thinking I might set up the chimney with a bend in order to collect wood vinegar (great for organic gardeners here).
Cheers!
Also I was gonna ask about what temperature you set it at, it looks like 500C from the graph (typo on the y-axis by the way but I forgive you as you’re American and working in your non-native units ;-)), I’ve managed to find most of these components but considering the source I’m buying it from (one of the Asian equivalents to a shittier than shitty Amazon) let’s keep fingers crossed that I a) don’t burn the garage down, b) don’t destroy my inverter, c) electrocute myself. Thanks once again Josh!
Also, I do apologise that I’m not using this yet for water filtration (I need something that will work on a pressurised system), but I’m sure you will agree that the use of biochar activated in compost is a great way for getting carbon back into the soil.
Sorry I am so slow to get back to you, Leon. I will try to answer a few things. One is that my observations have been that voltage output from my panels is pretty constant, even with indirect sun during time-of-day and low angle by season. But the amps are what vary. I bought a data-logging ammeter so I could track amps as these seem to be the sensitive factor for power output. Secondly, I have found that it's really important to have a good passage for the smoke to rise out of the system. If there are bends or occlusions in the chimney this could hind smoke egress and cause it to infiltrate inside the oven - where it causes all kinds of problems with the insulation and the wiring, etc. So at the moment I do not have a good answer for how to collect wood vinegar. I have been more focused on getting all the smoke associated chemicals out of the oven and burning them.
Thanks so much Josh, still in my to-do list but will get to it one day