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Meadville, PA 16335
Office: (814) 337-8223
Fax: (814) 333-4342


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8430 Rea Road
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Charlotte, NC 28277
Office: (704) 940-1867




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Anaerobic Digester - Bortnick Dairy, LLC

Project Overview

Bortnick Dairy LLC, anaerobic digester project involved installation of a mixed anaerobic digester, engine generator set and solids separator at Bortnick’s Dairy Farm to treat manure from 1450 dairy cattle and food waste.   The project produces biogas and manure solids for bedding.  Captured biogas is used for electricity generation that offsets the farm’s electric use with the excess being sold to the utility through a net metering agreement.  The project has been operational since May of 2009.  Data show that, from May 1, 2009 to November 22, 2009, the digester and engine-gen set generated 51,000,000 scf of biogas and 1,820,000 kWh electric, respectively. 

Input includes manure loading from onsite and four truck loads per week of food waste with each truck averaging 5,500 gallons of material.  Separated solids produced are estimated at 100 cubic yards per week based on sawdust replaced and sales to a landscaping company.  The $1.4 Million project was funded by Bortnick Dairy with assistance from USDA-RD and PADEP Energy Harvest Grants, and is providing over $280,000 in annual revenue to Bortnick Dairy.

Services Provided

Tom Wilson of WES served as Project Manager for construction of the Bortnick digester.  Services provided include: calculation of heat loss and heat exchange capacity of the digester; sizing pumps for heat transmission to the digester; assisting client in negotiations with utility for interconnection and electricity buy back agreement; recording and calculating environmental benefits of the project for grant reporting requirements; documenting expenditures and verifying installation for grant administration; air emission calculations and Air Quality Permitting determination.

Project at a glance

Project Cost:  $1.4 million
Estimated Annual Value:  $300,000
% Grant Funding:  43%
Project Size:  500 kWe
Status:  Operational
Additional Benefits: 

  • >3000 MWhe/yr produced from renewable sources
  • Methane destruction
  • Renewable Energy Credits (RECs)
  • Produces bedding
  • >1000 Mg CO2/yr emissions reductions

Click to view photos of the project
Click to view final report to PADEP