OpenTube

I Heated All My Water With a Pile of Woodchips (Building a Compost Water Heater)

John Connor

143,033 views

I heated all my hot water last summer using a pile of woodchips. No electricity. No propane. Just microbial activity!

In this video, I build and test two compost-powered water heaters (biomeilers), inspired by the work of Jean Pain, to see if microbes can provide enough heat for my everyday hot water needs.

Along the way, I share the challenges, failures, and lessons I learned - from exploding pipes and temperature monitoring to understanding the biology behind aerobic decomposition and why moisture, airflow, and the right carbon-to-nitrogen ratio make all the difference.

System 1:
10 Cubic Yards
Additional Nitrogen Source: Weeds and Grass Clippings
Max Water Temp: 58°C (136°F)

System 2:
30 Cubic Yards
Additional Nitrogen Source: Chicken Manure
Max Water Temp: 77.5°C (171.5°F)

Recommended Resources:
The Compost-Powered Water Heater by Gaelan Brown
The Methods of Jean Pain by Ida and Jean Pain
Teaming with Microbes by Jeff Lowenfels
The Humanure Handbook by Joseph Jenkins

Follow more of the build:

Instagram → @john7connor
TikTok → @john7connor

#OffGrid #TinyHome #Biomeiler #CompostWaterHeater #CompostHeating #compost #AerobicDecomposition #microbial #microbes #RegenerativeDesign #RenewableEnergy #SoilBiology #DIY #permaculture #soilhealth #soilfoodweb #sustainableliving
Follow more of the build:

Instagram → @john7connor
TikTok → @john7connor

00:00 Can Woodchips Heat Water?
01:16 Why I Didn't Choose Solar
02:05 How Microbes Generate Heat
02:44 My First Compost Water Heater (System 1)
04:05 Jean Pain & the Biomeiler
05:00 Building a Bigger Biomeiler (System 2)
10:11 Temperature Monitoring
10:40 My Biggest Mistake
13:16 Did It Actually Work?
14:15 More Than Just Hot Water

20 Comments

@elainaricci1501 3 weeks ago Pinned

We built one in 2022 and heated our house and water by connecting to our hot water baseboard boiler. We used 2,000 feet of pex and had a heat exchanger added to our furnace. We reached 150F in a week. We used it for a year and a half...2 winters in NE PA. The 2nd year it wasn't as efficient but still helped keep cost down. We have a 3,000 sq ft home and spend $6,000/ year for oil. So this was a huge savings. Life got busy, and we just couldn't get it built again. We are rebuilding this year. I like how you zip tied the piping to the hog panel. We just coiled it in piles and kept layering it. It was 20' in diameter and 10 ' high. Ratio was 60% fresh wood chips, 30% fresh saw dust, and 10% horse manure. We surrounded it like you did but with hay. We had a perforated black pipe at the bottom for air flow. We never got to put a solar fan on the pipe or adding the heat and moisture sensors. We will do both this time. What sensors did you use?

@annebarr9314 13 days ago

Well you needed the showers after that work.

@TimStevens-t6o 4 days ago

Hats off to you!, after all the work the first time, you doubled down and got it right ! Ive been researching these and thanks to you I now have answers . Appreciate you posting

@tdx110 13 days ago

You can build (or buy) a heat pump using a refrigerator compressor—you’d just need to change the refrigerant. This would allow you to extract heat from your compost pile, helping it last longer.
You could store the excess hot water in a boiler.

As for the excess heat, you could also build (or buy) a low-temperature turbine; from what I know, commercial versions operate at around 60°C. I also know it’s possible to build one yourself for lower temperatures without too much trouble. I wanted to build something like that myself, but... money.

@luvnotvideos 8 days ago

Thank you for showing failure as well as success. It really helps to understand the thought process behind your work. I look forward to future videos. 😀

@1voluntaryist 2 weeks ago

1982, I lived in the forest in Hawaii (big island), no electricity, on phone, in a tree house I had to reach by latter. I had shower water pumped up from two 50 gallon barrels that were filled when it rained. I hung a clear 2.5 gallon bag that got sunlight to warm up the water. I used 1 gal. to get wet, soap. 1.5 gal. to rinse. The water was lukewarm.

@AlterKater 10 days ago

I will have to scale it down a little for my balcony.

@m.j.v.4463 13 days ago

JOHNY BUILT THIS IN THE FOREST

WITH A BUNCH OF WOODCHIPS

@DavidEinax 2 weeks ago

You build the world to a better place. So thanksfull for the video/clip. God bless you. Have a long live ! Warm regards from germany

@Raadhuis1983 2 weeks ago

It’s all about the heat generated by the crop decomposition that provides your hot water—if I’m not mistaken.

@koningbolo4700 8 days ago (edited)

Well done man, what a great idea and what a great execution.

@sharperminds8509 1 month ago

Nicely done. Thank you for sharing your experience and design. I love the idea of being independent from the grid/system. We've gone whole house solar which of course provides our hot water heating. But we come up a bit short in the winter time when our consumption goes much higher. I love the idea of heating using other sources of heat generation. I remember growing up and tossing our lawn scraps over the hill into a ever growing pile. I was surprised to see the amount of heat coming off that pile, steam in the winter time. Great use of microbes. Thank you again and good luck with your project.

@john7connor.design Creator 2 months ago

If you've built a compost heater (or are even thinking about it), I'd love to hear your ideas or what worked for you!

@PIXELFLIP 1 month ago

Great inspiration! Nice edit as well

@daves4026 2 weeks ago

Totally worth the subscription

@LuSolutions 2 days ago

This is awesome! For winter i would do the same, just make it 3 times bigger (or three in parallel) then insulate and extra airflow (on a timer to conserve heat)