Compost Exhaust to Provide Nutrients for Plants in Biofilter and Heat for Greenhouse

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Commodities

• Vegetables: greens (lettuces), tomatoes

Practices

• Animal Production: manure management
• Crop Production: greenhouses, high tunnels or hoop houses, nutrient cycling, season extension
• Education and Training: on-farm/ranch research
• Energy: byproduct utilization, energy conservation/efficiency
• Natural Resources/Environment: carbon sequestration
• Production Systems: agroecosystems
• Soil Management: composting
• Sustainable Communities: food loss and waste recovery/reduction, food loss and waste recovery/reduction, food loss and waste recovery/reduction

We seek to partner with a local farm to demonstrate a system through which properly designed, integrated commercial compost systems and greenhouses can function synergistically, reduce operating costs, increase yields, and improve the profitability and sustainability of local farms while conserving soil and protecting water quality. We will demonstrate this through the capture of heat and gases from a midsize scalable reverse aerated compost system, in coordination with a greenhouse that is fully protected from the winter elements. 

We will use a carefully designed compost facility and greenhouse to study and optimize the correct balance of compost feedstock recipe inputs, aeration, temperature and biofilter plants and media to harness and conserve heat, nitrogen, carbon dioxide, and moisture as valuable inputs in our greenhouse. This will mitigate the release of these greenhouse gases into the atmosphere and reduce the further use of fossil fuels for heat, growth stimulation and fertility.

This project and facility is designed at the smallest functional size, for simple and cost effective establishment and operation by farmers. It is easily duplicated and scalable.

Our team works closely with a broad network of farmers, agricultural partners and compost champions, and has been developing case studies and best practices toolkits for composters for several years. These relationships, experiences and our organizational resources will enable our team to leverage resources to support this project, while sharing results in an effective, comprehensive and systematic manner.

This project seeks to:

1. Monitor and capture heat from the exhaust of active reverse aerated compost piles.
2. Demonstrate that this heat will make it more affordable and sustainable to operate a greenhouse in a cold climate. 
3. Capture carbon dioxide, ammonia, methane and nitrous oxide in a biofilter instead of allowing them to escape into the atmosphere.
4. Record and analyze nutrient data to minimize formation and leakage of CH4 and N2O into the environment.
5. Understand and document the effects of exhaust nutrients on worms and plants.
6. Experiment with different biofilter mediums, plants and lighting arrangements to determine best practice for producing profitable and nutritious crops.

We seek to demonstrate that composting and greenhouse production can be mutually beneficial endeavors, diverting food waste from landfills, increasing nutrient input to farms, decreasing heating costs, and increasing production which will increase profitability and quality of life for farmers.  This scalable and replicable project will make entry more affordable for farmers with financial constraints, enabling opportunity for marginalized populations.  The facility is scaled small enough, and designed to capture the gases and therefore odors, so it can easily be located within close proximity to waste generators.