Calculating piggery ammonia emissions

Piggeries are required to report to the National Pollutant Inventory (NPI) when they exceed one or more thresholds for reporting. Ammonia (NH3) must be reported when piggeries have more than 1,137 SPU. This project aimed to develop a method to more reliably calculate ammonia emissions from piggeries, taking into account different manure management systems.

Value for producers:

• Over-prediction of emissions may result in an increased regulatory burden and higher reporting costs for producers

Recommendations:

• Ammonia emission factors differ substantially depending on the type of manure management system.
• Revised ammonia emission rates are recommended for adoption in the NPI:

1. Conventional piggery (shed, uncovered pond - long HRT, land application on-farm) - 0.68
2. Conventional piggery (shed, short HRT, land application on-farm) - 0.46
3. Conventional piggery (shed, covered pond, no secondary ponds, land application on-farm) - 0.28
4. Deep litter (storage, land application on-farm) - no change
5. Deep litter (litter removal) - no change