Report in msa
- 1. Pig Housing Systems Designed to Manage or Adapt to Climate Change Presented at: Minnkota Meeting March 16, 2012 Larry D Jacobson, Professor & Extension Engineer University of Minnesota
- 2. Introduction • Generally accepted that climates in the major pig production areas of the U.S. (Midwest and Southeast) are becoming warmer with higher moisture or dewpoint temperatures. • A warmer and wetter climate will only increase the need to lower barn temperatures in production facilities, which is very limited in present building designs.
- 3. “Green Pig Barn” Project Objectives • Develop a swine finishing building for Midwestern U.S. based on building design criteria that reduces the housing system’s environmental footprint (lowers energy & water usage and airborne emissions by 50%) while maximizing utilization of manure/waste products • Provide guidance to retrofit existing finishing barns to reduce energy use and emissions.
- 4. Key Design Criteria • Integrated Design – No add on technologies that do not benefit the production system • Replace current 2400 head “tunnel ventilated” finishing barn in upper midwest (traditional deep pit with curtain or power ventilation) • Must account for total housing system emissions (e.g. manure storage emissions must be included)
- 5. Tunnel Ventilated Finishing Barn • Double wide- 2 – 1200 rooms or 2400 head total – approx. max ventilation 120 cfm/pig • Winter ventilation – mostly pit fans but some end wall fans using ceiling inlets • Summer ventilation – both pit and all end wall fans with primary inlets from opposite end wall curtain
- 6. Other Important Factors • Design should optimize the barn environment AND pig performance to offset added capital investment or labor costs Thermoneutral Zone
- 7. Heat Production in Growing Pigs 0 200 400 600 800 1,000 22 44 66 88 110 132 154 176 198 220 Pig Wt, lb BTU/hr Today Pre-1988 Trans ASAE 47(1):259-270 111% 115%
- 8. Other Factors to Consider • Design should improve worker environment and reduce safety hazards (foaming and H2S hazards with agitation and pumping)
- 9. Other Important Factors • Emissions, energy, and economics calculated on per pound of pork produced rather than on per area or animal number – Emissions may be more per barn but if more product (pork) is produced . . . we are getting less emissions per unit of production
- 10. Energy Use in Pig Production • Direct (Fossil Fuel) Energy – Primarily L.P. Gas and electricity – About 2 to 5% of pig production cost (UMN Farm Financial Management) • Indirect (Feed) Energy – Feed efficiency, rate of gain – Estimated to be 60 to 70 % of pig production costs
- 11. Key Emission Control Factors • Move manure out of the barn – avoid long- term pit storage of manure under barn – Reduces risks of pig losses during pumping – Improves Indoor Air Quality – Reduce ventilation requirements – Reduce barn emissions • Reduce ventilation • Reduce temperature
- 12. Mean Ventilation Rates over 12 months for Geothermal vs. Conventional Crated Gestation
- 13. Final Design Summary • 2400 head, double wide, mechanically ventilated barn • Ceiling inlets for 100% of ventilation air • Four barn versions (A,B,C,&D) – Flooring (partial slats - A & B & full slats –C & D) – Different Heating and cooling systems
- 14. Barn Design Options Matrix Partially Slatted Version A: Geothermal and heat pump for heating and cooling (PEX tubing) floor (40 T heating and cooling) plus direct fire for room heat. (80 cfm/pig max) Version B: Geothermal only heating and cooling of floor and room (135 T heating and cooling) (40 cfm/pig max) Fully Slatted Version C: Evaporative Cooling only (twice normal cooling capacity) (100 cfm/pig) Version D: Geothermal heating and cooling of room air (135 T heating and cooling) (40 cfm/pig max) NOTE: All barns include outdoor covered manure storage
- 15. Versions A and B
- 16. Versions C and D
- 17. Green grow-finish barn’s inlets & air tempering • Tempering halls at ends of barns for heat exchangers or cool cells • All air brought in through ceiling inlets
- 18. Energy and Emissions Estimates (in comparison with existing tunnel ventilated barns) Version of Barn Electric use LP use Emissions Version A Slightly more Slightly less less Version B Slightly less Slightly less Much less Version C Equal Equal Slightly less Version D Slightly less Slightly less less
- 19. Economic Evaluation1 Variables Considered • Investment • Feed efficiency • Death loss • Pig health cost • Electric use • LP use • Market Price • Other costs Constants • Start and end weight • Weaned pig cost • Days to end group • Between Group Time • Feed cost • Facility life 1Done by Bill Lazarus and Bob Koehler
- 20. Key Input parameters that were varied for the Economic Analysis Item Baseline Version A Version B Version C Version D Const. costs / pig space1 $260 $400 $510 $350 $525 ADG2 lb/day 1.55 1.62 1.66 1.60 1.66 FE2 lb feed/lb gain 2.75 2.55 2.45 2.60 2.45 1Bids from SW MN field engineers to build barn & manure storage 2,3Based on 2009 Finbin records of 36 farms with adjustments for cooled facilities
- 21. Economic Summary - Results Item Baseline Version A Version B Version C Version D Profit/pig $3.73 $6.65 $4.95 $8.18 $5.30 NPV1/pig space $5.95 $2.43 $9.03 $3.12 Years to Payback additional to baseline 1Net Present Value 9.1 12.8 6.0 12.5
- 22. Economic Analysis Discussion • Many assumptions & crude sensitivity analysis – Slight changes in animal performance (ADG and FE) will have dramatic impact on results – Feed costs will also have a large impact • Not captured by Economic Analysis – Worker health, regulations and permitting benefits, death loss (pigs) with agitation and pumping
- 23. Questions??
- 24. Heat Percent of air exhausted to remove CO2 Makeup air added to replenish O2 Pigs Add Heat, Moisture, and Gasses to Air Optional Antimicrobial Filter in makeup air Bacteria, Viruses, and Dust Removal Water to Air Heat Exchanger Heat Added Combination of Biotrickling and Biofilter H2S, NH3, and other Gasses Removal Water to Air Heat Exchanger Heat Removed for Dehumidification Moisture removed from air Water Heat StorageHeat A B C D E F G 24
- 25. • Develop a new barn design concept for swine production that would reduce emissions and improve feed efficiency. 25 Air Cleaner & Conditioner
- 27. Air Cleaner and Conditioner Units 27
- 28. 28 Biotrickling Filter Biofilter Air Inlet CO2 Exhaust Fan Heat/Water Storage Tank Air Return to Swine Room Heat Exchanger to cool air and Condense Moisture Heat Exchanger to Reheat Air Ambient Air Inlet Heat Pump
- 29. 29 60' 30' 100' 260' Instrument Room Shower Conference & Break roomBathroom Baged Feed Storage Area Mechanical Room Tunnel Ventilation Mechanically VentilationRecirculating Air Ventilation Office Observation Hallway