[deepnet]

A hot heap captures more carbon, releases less methane and makes much compost, much faster, from same amount of base material ( less evaporates ).

Ideally takes 6 weeks to compost a whole heap - using hot methods.

Also kills fungi & pathogen and all weed seeds and readily ‘eats’ ( dissolves ) carcasses and meat and other nature that should be avoided in cold heaps.

Takes a bit more management and monitoring but is easily automated.

[franktankbank]

> is easily automated.

At scale, in the backyard not so much. I'm open to being wrong though... got any sources of low scale automation?

[deepnet]

Yes !

tl;dr air pump saves turning the heap, insulation keeps heat in, currently Raspi sensing methane, moisture and temp controlling water & air inputs has improved my home hot heap yields 80% and completely automated it - 100% labor free.

The 4 key factors for a hot heap are moisture, temperature and oxygen and green ( high nitrogen ) to brown ( high carbon ) ratio ( approx 2 green to 1 brown by weight ).

I have a 1 cubic metre heap ( the minimum to generate the necessary heat ) and I have an specialised product, a double wall insulated ‘hot’ bin which keeps it working even in winter.

A hot heap steams so water input is necessary.

Hot heaps need oxygen, which is the hard part - manually turning the heap.

The temperature rises to 70 degrees C after a week, which kills all but the extremophile hot heap bacteria which are aerobic rather than the cold heap anaerobic bacteria.

I added an air pump input to the bottom and I have a water hose and sprinkler the top.

I run the air every day for 10 minutes. And the water for when it feels dry.

Now it never smells and composts in 7 weeks instead of 12.

I have now bought a methane, moisture and temperature sensors, electric valve for water and so a RaspberryPi is graphing the sensor inputs and recording the heap water and oxygen timings.

Very importantly, I have a pile to collect greens ( veg and grass ) and a pile for browns ( leaves and cardboard ) so I can fill the hot bin in one go.

Once I get some time I’ll write it up.

[oooyay]

Please link back when you do, this is really cool.