2013 Annual Report
As confidence in the silage model is established, this component will be incorporated in the Integrated Farm System Model. This whole farm model will be used in the simulation of farming systems to determine baseline, whole farm emission data. Mitigation techniques such as alternative silage facilities, feeding frequency, covers, and wind breaks will be evaluated to determine their potential to reduce farm level emissions and the ozone forming potential of those emissions.
The silage emission model will also be incorporated in an educational software tool called the Dairy Gas Emission Model or DairyGEM. This will provide a simpler tool with more graphical output for broader use in education and training of producers and others interested in silage production and feeding.
Cooperator spent time in California working with staff of the University of California in Davis designing and conducting experiments to measure silage emissions. An extensive literature review of work related to silage VOC production and emission was also completed. Data on VOC concentrations, volatility and reactivity in the atmosphere were summarized and used to refine and simplify our silage VOC emission model.
The revised silage VOC component was incorporated in our farm simulation model (Integrated Farm System Model) to enable farm scale estimation of silage VOC emissions along with other environmental impacts and farm economics. The silage VOC component was also incorporated in our DairyGEM software tool. DairyGEM (Dairy Gas Emission Model) is an educational aid for estimating ammonia, hydrogen sulfide, greenhouse gas, and now VOC emissions from dairy farms. Both software tools are now fully functioning and verified to predict reasonable VOC emissions as influenced by silage storage and management procedures. Further evaluation with measured farm data is underway to test the accuracy in predicting farm emissions.