Sunny Knoll Farms


Sunny Knoll Farms

Sunny Knoll Farms (credit:

Sunny Knoll Farms, Inc. in Wyoming County, NY, is a third generation family-owned farm that houses 1,500 dairy cows in three 6-row freestall barns.


The farm began looking into AD technology in 2005, whereupon construction of a horizontal plug-flow digester started in August of that year and was completed in July of 2006. Unlike most other dairy farms in New York state that have constructed anaerobic digesters, Sunny Knoll’s primary motivator was to offset electrical power costs. The three freestall barns are outfitted with cow cooling fans whose electrical loads, along with the electrical demands of cooling milk, are significant. Therefore, the farm desired to reduce their annual cost of power. Farm odor was not a significant issue for the farm; however, the addition of anaerobic digestion allowed for a proactive approach to be taken with regards to spreading manure on crop fields.


An additional benefit of the AD is the preservation of nutrients in treated manure. The risk of runoff and nutrient leaching is drastically reduced when manure is properly applied to crop land in accordance with a governing Comprehensive Nutrient Management Plan (CNMP).


At this time, the farm does not plan to switch to post-digested separated manure solids for bedding since they do not have, and do not plan to install, a solid-liquid separator.



IFES Number: 45

City: Perry

State: NY

Country: USA

Type of Firm: Farm

Main Products: Dairy; Bedding

Size of Firm: 1500 milking cows; 2200 total acres

Ownership Type: Private

Technology: Biogas

Energy System Components: Anaerobic digester

Operational Status: Operational

Year Installed: 2006

Energy Feedstock: Manure from 1800 cows

Energy Produced: Biogas production: 111,400 cu_ft/day; 12,721,064 kWh since inception (summer 2006) (he takes a daily reading)

Energy Uses: Cogeneration; Electricity

New co-products: Bedding

Money Saved: $100,000 on electric bill during their first year, but went down afterward

TCO2 Eq Avoided: 8,564 CO2E/yr