1. A plug-flow digester was observed and recorded data and compared to a covered lagoon and complete mix digester.
2. Capital costs range from $150,000-$300,000 for a plug-flow digester while electricity sales per year are $15,000-$30,000.
3. The major determining factor is the amount of available feedstock which relates to the amount of animals present on site. Larger farms can utilize larger biodigesters to produce more electricity on site.