Emissies van ammoniak en methaan uit melkveestallen in het netwerk praktijkbedrijven : Tussenresultaten van praktijkmetingen op 15 onderzoeksbedrijven

At 15 dairy farms, the barn emissions of ammonia (NH3) and methane (CH4) were continuously measured using sensors from March 2021 to March 2024. Additionally, spot measurements using reference methods were conducted. The average ammonia emission was 9.8 kg per animal place per year based on the spot measurements and 9.0 kg based on the continuous measurements. The average methane emission was 160 kg per animal place per year based on the reference measurements and 153 kg based on the continuous measurements. An relation between ammonia emission and ventilation rate was found with an interaction with outside temperature and windspeed. Grazing is influencing the validity of the methods for emission measurements. During the hours of grazing no emissions were measured. Therefore, inside in the effect of grazing on emissions is limited. Farms without in-house manure storage have an average methane emission of 128 kg per animal place per year, which is 14% lower compared to farms with a standard slatted floor. Benchmarking offers opportunities to improve management and reduce emissions within a group of comparable farms.