Your SlideShare is downloading. ×
Stefan Grimberg: Energy From Cows, Biogas Digesters for Dairy Farms
Upcoming SlideShare
Loading in...5
×

Thanks for flagging this SlideShare!

Oops! An error has occurred.

×
Saving this for later? Get the SlideShare app to save on your phone or tablet. Read anywhere, anytime – even offline.
Text the download link to your phone
Standard text messaging rates apply

Stefan Grimberg: Energy From Cows, Biogas Digesters for Dairy Farms

4,861

Published on

Stefan Grimberg of Clarkson University discusses how to capture energy from Dairy Farms.

Stefan Grimberg of Clarkson University discusses how to capture energy from Dairy Farms.

Published in: Technology, Business
0 Comments
3 Likes
Statistics
Notes
  • Be the first to comment

No Downloads
Views
Total Views
4,861
On Slideshare
0
From Embeds
0
Number of Embeds
1
Actions
Shares
0
Downloads
426
Comments
0
Likes
3
Embeds 0
No embeds

Report content
Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
No notes for slide

Transcript

  • 1. Converting Dairy Manure into Energy. An introduction to anaerobic digestion of farm waste Stefan Grimberg Associate Professor Dept. Civil Environ. Eng Clarkson University
  • 2. Thank you to Floyd Schanbacher
  • 3.  
  • 4. Anaerobic Digester Potential Benefits
    • Odor Control
      • Reduced liability
    • Manure stabilization
      • Help with nutrient management
      • Soil stability
    • Energy generation
      • Offset farm electricity requirements from grid
      • Sale of extra energy
      • Heat generation to reduce fuel required
    • Reuse of bedding solids
      • Offset bedding cost
  • 5.  
  • 6.  
  • 7.  
  • 8.  
  • 9.  
  • 10.  
  • 11.  
  • 12.  
  • 13.  
  • 14.  
  • 15. Plug Flow Digesters
    • Little mixing
    • Few mechanical parts
    • Simple
  • 16. Mixed Digesters Mechanical mixing in tank More gas production Slightly higher capital cost
  • 17. Community Digester Behringen co-fermentation plant in Germany
  • 18. Digester Feed
  • 19. Large-scale Digester Performance
  • 20. Capital Cost of Manure Management Technology Source: AgStar Publication:
  • 21. Digester economics
    • Dr. Fick’s estimated fixed of $660 per cow is a little low for the farms we are looking at.
    • Tinesdale farm (in Minnesota), with1800 cows, invested about $1,000 per head.
    • Good estimate $1,000 per cow?
    • At this capital assumption AD system become economical based on sold energy alone at power sale price of $0.09/kWh.
    (Mehta, 2002)
  • 22. Case Study
    • Gordondale Farms, Nelsonville, WI
    • 750 head dairy
    • Sell biogas to utility that generates electricity on site, utility owns and operates generator
    • Sell at 0.015 $/kWh generated
    Martin, J.H., 2005. An evaluation of a mesophilic, modified plug flow anaerobic digester for dairy cattle manure. Final report for EPA contract GS10F-0036K
  • 23. Summary
  • 24. Martin, 2005
  • 25. Martin, 2005
  • 26. Martin, 2005
  • 27. Martin, 2005
  • 28. Martin, 2005
  • 29. Martin, 2005
  • 30. Martin, 2005
  • 31. Martin, 2005
  • 32. Economic Evaluation
    • Capital costs with co/gen: $748,000
    • Annual sale of power: $18,396
    • Avoided annual bedding cost: $60,000
    • Sale of extra solids: $8,600
    • Total benefits: $86,996
    • Payback period: Approx 6 years.
  • 33. Digester Systems Model Digester Solids Sep. Cogen Manure Other Input Biogas Electricity offset Surplus electricity Surplus heat Spread liquid fraction Solids for bedding Sale of solids Solids field application Heat
  • 34. Example
    • 500 cow dairy
    • Free stall barn
    • Scraped manure
    • Include flush from milking parlor
    • Northern NY
  • 35. Model Estimate: 500 cow dairy -$1.8 Annual Net Benefit per Cow without excess heat and methane credits $13.54 Annual Net Benefit per Cow if excess heat cannot be sold $38.27 Annual Net Benefit per Cow $111,463 Total Annual Benefits $10,000 Onsite Fiber value $16,739 Tax Offset $8,495 Farm savings-Thermal (internal) $25,171 Farm savings-Electric (internal) $4,203 Renewable Energy Tax Credit $7,646 Methane Credit $12,368 Thermal Sales (surplus) $17,707 Electric Sales (surplus) $9,133 Fiber sales Potential Annual Benefits $23,553 Maintenance, Repair Annual Operating Costs $68,774 Total Annual Cap. Cost over 10 yrs $656,180 Digester/Cogen system Capital Cost Cost/Benefit Item
  • 36. Run Digester Model
    • Demonstrate:
      • Effect of size
      • Power cost
      • Bedding off set
    • Any scenarios of interest?
  • 37. Conclusions
    • Anaerobic digestion of manure has significant potential to decrease fossil fuel use in rural areas.
    • Community digesters may be very cost effective due to larger scale and mixed feed composition
  • 38.  

×