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Biogas / Anaerobic Disgesters Energy Self Assessment

The biogas self assessment tool was developed to increase awareness and utilization of anaerobic digestion processes and renewable energy production in agriculture. Biogas is a product of the anaerobic digestion process comprised of methane, carbon dioxide, and trace amounts of other compounds. Biogas can be used for generating electricity, thermal heating or cleaned and sold as renewable natural gas. The biogas self assessment tool will assist farm producers in evaluating their farm’s potential for producing biogas to generate electricity and methane as renewable energies. The tool will assist producers in determining biomass feedstocks that are available on-farm and calculate the biogas production from the different feedstock sources.

This tool does not provide a site-specific renewable energy assessment. It evaluates thermal energy use based on user input.

Digester Basics

What is anaerobic digestion?
What are the common types of anaerobic digester systems?
What is an anaerobic digester feedstock?
What do the terms psychrophilic, mesophilic, and thermophilic mean?
What are the roles of methanogenic and acidogenic bacteria?

Usable Energy From Digesters

What is the difference between methane gas, natural gas, and biogas?
What can biogas be used for?
What is the efficiency of electrical production from biogas?
What is the difference between an engine-generator and a microturbine?
What is combined heat and power (cogeneration)?
What is the difference between a synchronous and an induction generator?

What goes in? What comes out?

What is left after anaerobic digestion is complete?
Can the solids be removed from digested effluent or manure? How?
What can the separated solids be used for?
Does the digestion process kill weed seed or the organisms that cause diseases like Johne’s ?
What happens to the major nutrients during anaerobic digestion (carbon, nitrogen, phosphorous, and potassium)? Can the effluent be applied to crop land?
Do anaerobic digestion systems affect the odor associated with manure storage?

Financial Considerations

How much does an anaerobic digester cost?
What are the labor and monitoring requirements of an anaerobic digester system?
What is the difference between net metering and a power purchase agreement?
What types of incentives or tax credits are available for biogas generation systems?
Can I invest in renewable energy without owning my own equipment?

Installation Information

I am interested in installing an anaerobic digester. How do I get started?
How can I find a reputable installer of anaerobic digester systems?