Abstract: Modular systems are disclosed for composting organic waste. The systems include a number of modular containers for holding predetermined amounts of the organic waste materials, these amounts being selected such that a relatively uniform temperature profile may be maintained within each of the modular containers. Each of the containers also includes an air inlet and an exhaust so that air may be circulated through the organic waste materials in each of the modular containers, a temperature probe for measuring the temperature in the modular containers, and a fan for circulating air from the exhaust of a first modular container to the air inlet of a second modular container when the temperature in the second modular container is greater than the temperature in the first modular container by a predetermined temperature difference, so as to accelerate the composting of said organic waste material.