UK PIG producers are now able to provide evidence of their efforts to reduce ammonia emissions, saving producers an estimated £15.3 million.

The results from AHDB’s accelerated ammonia monitoring trial enable the pig industry to firmly demonstrate compliance and best practice, removing the need for environmental mitigation costs. Pig producers must meet the Best Available Technique (BAT) Associated Emission Levels (AELs). If they cannot prove they are doing so, they must pay these mitigation costs.

The AHDB trial provides that proof and allows for updates in regulating the sector through accurate annual pollution inventory reporting and future habitat risk assessments.

The trial has provided a comprehensive and valuable study of ammonia emissions from different pig production systems, improved the industry’s understanding of emissions from the pork sector and demonstrated the reduction in emissions.

The Environment Agency has used the results, along with previous monitoring trials and older National Atmospheric Emissions Inventory (NAEI) data, to inform draft emission factors which will be published later this year. Importantly, these new emission factors demonstrate that UK pig housing is fully compliant with the BAT AELs and shows a decrease in the quantity of ammonia emitted from English commercial pig housing.

AHDB knowledge transfer manager, Zanita Markham, commented: “We are delighted to be able to present the most comprehensive and recent study of its kind. It demonstrates compliance on all housing types, which is to the industry’s credit. Importantly, it also sets a benchmark against which we can measure further reductions in emissions in the future.”

The aim of this trial was to establish eight new ammonia emission factors for a specific and representative range of pig housing types. The results not only provide these, but also demonstrate that farmers have decreased ammonia emissions since the historic data was first published.

Until this trial, the EA used emission factors based on NAEI data. However, not all these figures met the BAT AELs for pig housing. Natural England also uses the emission factors as part of planning applications. The report and findings are available for Defra to use for annual reporting for international air quality obligations.

An EA spokesperson said: “We are really pleased to have worked with AHDB to provide evidence that will continue to support permitting decisions for the industry for many years to come."

Highlighting the benefits of stakeholder collaboration, AHDB senior environment scientist, Harley Stoddart, added: “Through working with an excellent contractor and group of producers, as well as the Environment Agency and Defra, this project has demonstrated the benefits of collaboration by providing robust evidence of ammonia emissions from a wide range of modern pig production systems.”