Compost Aeration and Heat Recovery 

Compost Heat FAQs

• What is compost heat?  (heat produced by microbes as they break down organic matter, primarily carbon but supported by ideal composting conditions including C:N ratio, moisture, and feedstock degradability)
• What temperature is compost heat?  (compost must first heat itself up to a high enough temperature to be useful, and then produce excess heat we can harvest for our own use.  This typically occurs with relatively large or well-sheltered compost piles, at temperatures from 140 to 160 F)
• What is compost heat good to use for?  (160 is hot enough to burn you, but much cooler than combustion of wood or fossil fuels which can be 500 to 3000 degrees.  Heat is also released more or less continuously by a hot compost system, whereas many heating systems cycle on and off frequently.  Because of this, compost heat works best in a relatively low-temperature heating system with thermal mass - such as a radiant slab, aquaculture system, or heated seed beds.)
• How can I capture heat from compost in a useful form?  (Compost heat can be captured directly (by putting compost inside a structure you want to heat, or blowing compost exhaust into your heated structure), or by using a heat transfer loop.  Direct use is simple but also introduces odor, moisture, and potentially corrosive gases into your structure (these can be somewhat mitigated by a biofilter).  You can capture heat by coiling a long pipe or tube in a compost pile, which has been shown to work but has issues of efficiency and the waste of broken pipes.  Agrilab systems simultaneously manage your compost and capture heat continuously with our specialized heat exchanger system, which is then tied into heat loads with insulated pipes.
  
  

CAHR is how Agrilab Technologies provides efficient composting while harvesting the largest portion of thermal energy available.