1. Assessing the Commercial Feasibility of Manure to Energy Systems
Kraig Westerbeek
AVP, EHS
Murphy-Brown LLC

2. Current Manure Management Systems in the USA1. 2. 3.
Evaporation pond Sludge Land, Landfill

3. Manure to Energy? Manure from animal operations does have energy value
Swine manure = app BTU / pound
Animals are not 100% efficient in converting feed energy into body mass
Relative measure of efficiency is feed conversion (swine 3 : 1)

4. Manure to Energy?
Energy not used by animal can be recycled to other forms of useful energy
While gasification and or combustion are options for some dry manures, anaerobic digestion seems to have the most potential for deriving energy from animal manure

5. Potential for Anaerobic Digester Energy in the United States.
Turkey: 3,100,000 tpy*
Others (veal, lamb, mutton): 158,500 tpy*
Swine: 11,650,000 tpy*
Chicken: 18,750,000 tpy*
*tpy: tons per year
Source: AMI, 2011
Cattle: 13,300,000 tpy*
Manure energy: 10,000 – 20,000 MW power equivalence

6. “Anaerobic digesters, commonly in the form of covered lagoons or tanks, are designed to stabilize manure and optimize the production of methane.”
EPA AgStar – AD101

7. Number of Operating Anaerobic Digester Projects (US, July 2010)
Dairy
126
Swine 24
Poultry 5
Beef 2

8. Biogas Use for Operational Projects
Cogeneration 78
Electricity 48
Boiler / Furnace Fuel 20
Flared Full Time 15
Unknown Use 7
Pipeline Gas 4
Vehicle Fuel 1
Methanol

9. Energy Production by Anaerobic Digester Systems: 2001-2010 (EPA AgStar)

10. Concept schematics Generator Digesters Buffer tank Surge tank
Swine
barn
Develop: Dewatering system to produce dry organic fertilizer
Swine manure is scraped and collected in the surge tank.
Develop: Solids are further dried with waste heat and processed into organic fertilizer or used as fuel for combustion at a biomass plant
Wastewater is pumped to existing lagoon and irrigated with existing irrigation equipment
Biogas
Electricity
distribution
grid
Digesters
Buffer tank
Generator
Surge tank
Combination of above-ground and in-ground fermentation leverages the cost and engineering advantages of both design.

11. Manure to Energy – Commercial Feasibility
Fact: The technical feasibility of creating energy from manure has been proven
Question: Can energy be created at a cost that makes manure to energy commercially feasible on a large scale?

12. Commercial Feasibilty
To be attractive, manure to energy projects must create value for:
Investor (long term, stable return)
Farmer (avoided costs / increased revenue, improved manure management system)
Energy User (reasonably priced renewable energy)

13. Cost of Manure to Energy Systems
High capital investment typically required (example – swine manure $5-10M per MW electricity)
Various state and federal renewable energy credits help reduce initial investment
Operating costs vary depending upon system used, but are significant, particularly if transportation of manure is involved

14. Revenue from Manure to Energy Systems
Direct payment for energy based on current market value
Renewable energy credits – vary from state to state depending upon legislative requirements
Tax benefits (state, federal)
Carbon credit value (destruction of methane)

15. Benefits to Manure Management Systems
Significant destruction of volatile solids / reduced organic loading on existing system (increased treatment capacity)
Reduction of total solids leaving a more nutrient dense solids stream
Potential reduction of odor and emissions
Reduction of pathogen loads

16. Commercial Feasibility
Investments in manure to energy projects are risky due to the constant variability of manure characteristics
Advances in technology (anaerobic digestion, etc.) have reduced the risks substantially
State level renewable energy mandates have created a market for manure to energy projects by making returns more attractive
Depressed carbon market has been a negative

17. Circle 4 Farms Project
In the late 1990’s and early 2000’s, our company invested a significant amount of money in an anaerobic digester project at Circle 4 Farms in Utah
The goal of the project was to capture methane generated from the anaerobic digestion of swine manure and convert it into biodiesel

18. Anaerobic digestion Plant at Cirle 4: Utah

19. Methanol Production from Biogas, Circle 4, Utah

20. Circle 4 Project
The project failed due to problems associated with manure transport and lower than expected manure energy value
While technically feasible, the economics of the project did not work
The digesters built for this project are no longer in use
This project may have worked with today’s renewable energy incentives

21. Murphy-Brown Strategy
Instead of investing internal capital in manure to energy projects, MB has sought out partnerships with project developers and investors
Current projects
Alpental Energy – Utah
Pacolet/Millikan – North Carolina
Ag Power – North Carolina
Roeslein - Missouri

22. Summary
The technology is available today to support manure to energy projects – continues to improve with experience
Economic drivers have been added to provide the necessary revenue to support projects
The number of manure to energy projects continues to increase

23. Summary
I believe manure can compete well in the renewable energy marketplace based on both its price relative to other renewable energy sources, and its reliability in delivering continuous energy
I expect a continued increase in the number of manure to energy projects