[UPDATE 10/21/2021 -After 2018 I started posting my updates on my Patreon page, and so I'm filling in the back-logs for this project retroactively so the whole story is in both places. You can also read all of these posts with their original photo formatting here]

September 30th, 2020-

Hello dear patrons! To be honest, this month has been a rough one. Nothing instills a sense of impending doom quite like a week of breathing poison air. The wildfire smoke that choked the west coast made it hard to do much of anything for a while there, and I spent a lot of time this month thinking about the incredible power of biomass.

At the beginning of September, a small group of friends went out camping in the Alvord Desert in South-eastern Oregon, over the week that Burning Man usually happens. For those of you who are unfamiliar with Burning Man culture, there is a tradition to build a giant wooden structure called the temple, where people write their hopes, and fears, and grief, and loss, and whatever else in sharpie on the wood, and then watch that structure burn on Sunday night. It is a powerful and cathartic experience that is difficult to describe. 

This year, with Burning Man cancelled and an extreme burn ban in place for all of Oregon, we opted instead to make a mini temple out of wood scraps, and to not burn it. Instead, I packed all the bits back to Portland, and loaded them into my Biochar Reactor, to make into charcoal and energy, which seemed fitting.

Someone asked me while we were in the desert why I was "so into biochar" and the question gave me a chance to articulate something that I hadn't previously been able articulate. Biochar is all that remains when all of the volatile organic compounds have been driven off from any formerly-living matter in the absence of oxygen. Biochar is pure carbon, embodied sunshine, proof that something has both lived, and died. 

It is the ultimate symbol of death and rebirth. The pores in charcoal hold onto essential nutrients, like phosphorus, potassium, and nitrogen, that plants need to grow, and it keeps those nutrients from washing away with the rain. The char itself is not actually consumed by plants, but it provides the perfect physical substrate for nutrient retention and bacterial and fungal growth, so that new plants can sequester more atmospheric carbon, and generate new biomass, which in turn can be made into to new biochar.

One of the big problems that I've been trying to solve with this project has been how to utilize biomass energy effectively and efficiently. I've been able to run my little harbor freight generator using the syngas produced from making biochar for over 2 years now, but the process is impractical- I have to pull-start the generator every time, and the electrical power is only available while the engine is running. Also, I have gotten the generator to run on the direct output of the reactor, but it doesn't run fast enough to kick into "output" mode, which means that I need to store and pressurize the gas first, which complicates things significantly.

In order to be really useful, and not just a proof of concept, the process needs to be significantly streamlined, so that the engine could just start itself whenever the battery gets low, and efficiently charge a DC battery bank, just like a solar panel does, so that the energy produced can be stored for when it's needed in a fully off-grid system.

So naturally, I took my generator apart to see if I could find a  better way to get power out of. It turns out that the generator I have (and all "inverter" style generators) uses essentially the same kind of brushless DC motor that electric bike wheels do - because brushless motors make very efficient motors AND generators. 

On a hunch, I bought an open source electric motor controller called a VESC (A FSESC6.6 to be exact) and hacked it into the actual generator part of the generator, to see if I could spin it using just battery power without using the pull-start at all.

It's kind of a crazy idea, but turns out it actually works! I was able to crank the engine just by giving signal to the motor controller, instead of using the pull-start, effectively turning it into a remote-start generator, which is neat!

But what I'm really interested in is that the FSESC controller also has a 60 amp regenerative braking feature, designed to let an electric bike recharge the battery by using the motor as a generator. Since I already know the generator can be used as a generator, I'm hoping that this means that with the VESC I'll be able to electric start the generator, and then efficiently charge the battery with the regenerative braking feature once the engine kicks on under biomass power, which would be a lot more efficient and less dependent on engine speed than using the onboard electronics.

Unfortunately I haven't been able to try that part just yet, but I'm hoping to in the next few days.

This approach still needs a lot more testing, but the initial results are really intriguing. If it works, an approach like this could make biomass energy a lot easier to integrate into an existing off-grid solar power system, and allow people to generate power while reducing their wastes to biochar!

Thank you all so much for your support, and a big thanks to James, for helping answer all my questions as I got the VESC set up. Stay tuned for more updates!

Onward!

Sam