Greenhouse Gas Emissions from Covered or Uncovered Earthen Manure Storage
Average season and annual emissions were calculated for different earthen manure storage technology. Nitrous oxide and surface emissions were negligible. As ambient temperature increased, so did emissions as promotion of more biological activity occured. Straw-covered systems reduced carbon dioxide and methane by 57 and 85% each when compared to the uncovered system. Negative air pressure cover reduced carbon dioxide and methane by 62 and 60% respectively compared to uncovered systems. Straw covered systems costs are associated with manual labour, bales, equipment for application and size of storage which changes the coverage needed. The negative air pressure system costs include the system itself, annual cost to run the fans and early maintenance. Over its 10 year life expectancy it has an annual cost of $5,845 compared to $10,151 for the straw covered system.