[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]

May 31st, 2021

Hello dear Patrons! 

This has been an exciting month! At the end of last month, I finally got the generator running reliably on biomass gas, and was able to generate 250-350 watts at idle, with a peak of 700-800 watts when I put the gas under higher pressure. This month, I was able to run a few more experiments, and was finally able to run the generator continuously for over 20 minutes until I turned it off.

This generator produces 24 volts DC instead of 120 volts AC like most generators, which means it integrates really easily with existing systems already designed for solar panels. Here I've got the generator charging up my 2.4kWh lithium battery bank, and I can use that battery bank to power the reactor (700W), or the shredder (600W) or the trash printer (200W).

The limiting factor now is my ability to store the gas that the reactor produces. I can only store about 40L of gas in my gasometer, which can run the generator for about 5 minutes. So I started experimenting with pumping air into the reactor once it was started, in order to generate additional heat and gas, like stoking a fire by blowing on the hot coals. 

I got this special remote control valve so that I could pump air into the reactor without letting the gas escape when the pump wasn't running. This way, I can give the pump and valve 12 volts and the pump will start and the valve will open, and then when I turn off the power, the pump turns off and the valve closes.  

I was able to run the generator for about 20 minutes that way. I also tried recirculating the exhaust from the generator, and that worked surprisingly well, but not great. 

The problem is that doing that dilutes the gas with nitrogen and CO2, which makes the gas less calorific, and throws off the air-fuel mixture in the generator, leading to less power, and less reliable starting. The gas remains flammable and can still be burned in the flame tube, but it doesn't have the energy density the generator needs to really get going.

So, with your support from last month, I ordered this giant gas bag, designed for storing biogas, which just arrived today. These bags are cheaper to buy and easier to use than the gasometer I have been using, and don't require any water to work, which makes them a considerably lighter and more portable option. 

This bag is 0.5 cubic meters, or 500L, or roughly 130 gallons. That should be able to hold roughly 5000 watt-hours of chemical energy, which the generator should be able to convert into roughly 500-600 watt-hours of electrical power.

This coming month, I plan to use my Patreon budget to buy a decent battery monitor and a 24V battery bank, so that I can more accurately measure the energy consumed and produced by the system, and start running the system completely off the grid, using exclusively solar power and power produced from biomass.

Stay tuned!