Evaluation of Greenhouse Heating Potential using Compost Heat Recovery

The Na-Cho Nyàk Dun First Nation had recently reacquired an agricultural property within their traditional territory roughly 1 hour south of Dawson City. The farm had been developed with livestock and vegetable production in mind, and came with an abattoir and greenhouses.

BCE was commissioned to take a close look at whether it would be possible to use heat recovered from on-farm composting of slaughter waste and crop residues to supplement greenhouse heating requirements, particularly in the fall, early winter and early spring. Working with farm management we developed projections for crop and livestock production to estimate future potential compost production and timing. Various compost heat recovery systems and methods were researched and assessed for practicality and efficiency, with an air-to-water system being identified as the most practical and efficient. Potential compost heat production was modelled using high and low yield estimates based on the most recent research available.
Climate data for the area was modelled to determine potential greenhouse heat loss. Finally, the greenhouse heat loss and compost heat gain were temporally compared to determine the overall feasibility of the concept.

It was found that the concept had excellent potential to complement the farm enterprise through the efficient use of heat that would normally be lost, whilst boosting food security and energy independence. Financially, compared to fossil fuel heating systems, the compost heat recovery system could potentially pay for itself in a matter of a few years.