UNH Organic Dairy Farm Agroecosystem Study, Phase II; A closed system, energy independent organic dairy farm for Northeastern U.S.

2012 Annual Report for LNE11-313

Project Type: Research and Education
Funds awarded in 2011: $392,658.00
Projected End Date: 12/31/2014
Region: Northeast
State: New Hampshire
Project Leader:
Dr. John Aber
University of New Hampshire

UNH Organic Dairy Farm Agroecosystem Study, Phase II; A closed system, energy independent organic dairy farm for Northeastern U.S.


The current project, funded in the fall of 2011, is the second three year award for a projected nine year project. Our original grant for the first three years was completed in the fall of 2011 and a final report has been submitted. This report covers the first full year of the second award, and will not repeat the achievements under the first three years.

Objectives/Performance Targets

The overall purpose of this project is to use the Organic Dairy Research Farm (ODRF) as a test bed to achieve a closed-system, energy independent organic dairy farm for the northeastern U.S. We are pursuing a farm-ecosystem level approach to the measurement all of the material and energy flows occurring across the annual production cycle at the ODRF. Natural and human vectors are being compared, including, for example, inputs of nutrients in precipitation, feed and fertilizer, and losses in product shipment, surface water runoff and ground water leaching. The following text lists the goals for the first three years of funding. Results in these areas have been summarized in previous reports.

Objectives for the second round of funding:

1. Hydrology and water quality

a. Continued hydrologic investigation

• Year 4: Continue monitoring of main watershed. We had envisioned an extension of efforts into an adjacent watershed (establish stream gauging station, install additional wells). Initiate routine monitoring of soil moisture. Given the difficulties in closing the water budget in the main watershed, we have decided to continue to focus our efforts there as closing the water budget is critical to meet objectives of understanding agricultural impacts on region (ongoing).

b. Continued water quality monitoring

• Year 4: Continue monitoring to document the effectiveness of changing farm management practices (including the new barn and feeding station now in place and proposed changes in manure processing described below) on nutrient losses from the site (on-going); and quantify the role of the wetland in reducing off-site nutrient losses (study initiated).

c. Calculating the water footprint of the farm

• Meter the (blue) water used in stock tanks and washdowns (on-going).

• Compute the (green) water taken up by evapotranspiration in the growing of forage and the production of pelletized feed and bedding (on-going).

• Quantify the amount of (gray) water that leaves the site impaired (on-going).

2. Closing the Nitrogen Cycle

a. Measurement of gaseous N exchanges

• Quantify the inputs and losses of N to the pastures by N fixation and denitrification (initiated).

b. Updating data on the nitrogen cycle

• Continue to measure and monitor nitrogen inputs and output in products purchased and sold, and N dynamics associated with water balances (ongoing).

c. Minimizing nitrogen input

• Based on cycle analysis, recommend practices to limit N inputs (on hold pending results from 2.b).

3. Moving toward energy independence

a. Finalizing the current energy budget and energy system analysis.

• Continue to monitor energy use across the farm. Support a student who will formalize initial analyses of alternative energy systems for the farm, and develop and test solutions (ongoing).

b. Geothermal application for milk cooling.

• Develop a geothermal well on site and, using the specifications of different possible components of the three approaches outlined in the original proposal, identify the combination most likely to reduce the use of electricity (ongoing).

c. Integrated wood shavings/bedding/energy/compost system.

• Develop aerobic composting facility and acquire wood shaving equipment to test different operational approaches to reducing expenses for bedding and energy (Major activity this year, see “Accomplishments/Milestones” and “Impacts,” below).

d. An alternative energy demonstration center.

• Develop a single location where energy gain from a solar collector, energy output from the composting system, energy exchange in the geothermal cooling system, and a simple estimate of available wind energy developed from anemometer readings will all be available in real time (on hold in year 1).


1. Hydrology and Water Quality

a. Continued hydrologic investigations.

In this first year we have increased the durability and range of stream flow monitoring system. The Parshall flume installed in the main stream discharging the farm was reinforced with pond liner upstream of the intake to prevent leaks and short-circuiting around the flume in conjunction with the newly funded EPSCoR project. In addition a V-Notch weir was fabricated to insert into the flume to measure the low flows typical of summer months. Efforts to quantify the hydrologic stores and flowpaths were extended upstream to 1) quantify the fluxes into and out of the main forested wetland that is hypothesized to play a significant role in biogeochemical cycling and 2) quantify the residence time distribution of the pond. Ground water and surface water modeling continue to provide a framework for quantifying the water budget and fluid pathways.

b. Continued water quality monitoring.

Water quality monitoring has continued monthly for nutrients and major ions in all groundwater wells, in all ponds on the farm, and in the creek draining the wetland below the dairy operations. Our understanding of water quality will be greatly enhanced by deployment of state-of-the-art water quality sensors with separate funding. The sensors will monitor nitrate, organic matter, specific conductance, pH and suspended sediments in real time. These data will be collected continuously and streamed live on the web.

c. Calculating the water footprint of the farm.

To date, we have developed an algorithm using data from previous years that takes into account pelletized feed composition; balage amounts, dates, acreage; measured pasture yield and forage schedules; and evapotranspiration computed from local meteorological data.

2. Closing the nitrogen cycle.

a. Measurement of gaseous N exchanges.

Sampling of nitrous oxide gas fluxes from the wetland has been initiated to estimate rates of denitrification. In addition to gas fluxes from the wetland surface, we are also measuring N2O in groundwater, and the isotopic composition of nitrate in selected groundwater wells. Each of these measurements will be used to help constrain the spatial variability in denitrification, and quantify its significance for the overall N budget.

b. Updating data on the nitrogen cycle.

Monitoring of all inputs and outputs of nitrogen to the farm has continued. This includes the major transfers of products imported and exported, as well as background biogeochemical processes.

c. Minimizing nitrogen input.

On hold pending results from 2.b.

3. Moving toward energy independence.

a. Finalizing the current energy budget and energy system analysis.

Monitoring of energy usage on the farm continues.

b. Geothermal application for milk cooling

It has been determined that the system with the lowest capital costs (and the most likely to be adopted in practice) is to use the existing water well to produce water that will be run through a plate heat exchanger and discharged into stock tanks. This requires no new wells and offsets the water needs for the stock tanks. The system is slated to be installed in early 2013 and will serve as a pilot for receiving Renewable Energy Certificates for the thermal energy produced under New Hampshire’s new Renewable Standards Portfolio statute.

c. Integrated wood shavings/bedding/energy/compost system.

With regard to the on-farm animal bedding production project, we finalized which machines would be most suitable for our farm, and similarly-sized farms throughout the New England region. We analyzed industrial chippers with screens, tub grinders, and shaving machines. Part of our analysis involved going to the Northeastern Forest Products Equipment Expo in Vermont to see the various machines in action and to collect biomass samples to determine the overall quality of the material. Within this analysis, we looked at cost, ease of use, and time commitment to produce the material. For companies that were not present at the trade show, we obtained operational manuals, specs, and bedding samples via mail.

In addition to an analysis on the machines available for the production of bedding, we also completed a one acre patch cut at the UNH Organic Dairy, to provide biomass needed for the bedding research project. The one acre patch cut, which was completed this past August, produced 55 cords of eastern white pine, and five cords of eastern hemlock. We intend on comparing these two species as a bedding product. In addition to harvesting biomass, we also completed a stem analysis on fifty eastern white pine trees. The goal of this analysis is to break down the tree into various woody products, including shavings, and determine the most profitable way to manage the woodlot under this type of regime.

A final output within this project was the development of the on-farm animal bedding production model. The goal is to provide farmers with an easy-to-use model that will allow them to plug in their own farm variables and determine whether it is profitable to purchase a shaving machine. We are still testing the model and will refine it further following the running of the bedding machine. Outreach for this portion of the project has included discussions with local sawmills, which are the primary providers of woody animal bedding in the region.

Output for the heat-recovery compost facility has come in the form of developing the most economic method to build such a facility. As these facilities are in their infancy, our research team has spent the past year working closely with UNH engineers and those from Milestone Engineering and Construction Inc. to develop and design a facility that can be replicated by farmers and institutions alike. Facility completion is scheduled for February 2013.

Output for this portion of the project has been in the form of initial guidance for the possible construction of a similarly-sized composting facility by a local composting business. Site visits and initial economic data have been provided to help this business reach their goal of building an aerated composting facility.

d. An alternative energy demonstration center.

On hold in year 1.

Impacts and Contributions/Outcomes

Recurring impacts of this project, consisting largely of visitor days and class use by UNH and surrounding institutions (including K-12), have been highlighted in previous reports.

In the last two months we have take steps to increase direct contacts with stakeholders and practitioners. In particular, we have:

• Developed a link to the advisory group developed by Andre Brito and others for their NIFA OREI regional award on organic diary operations. We will take part in meetings of that group, and be able to access their feedback and ideas.

• Arranged to present on overview of the wood shaving-bedding-compost project at the annual meeting of the Northeast Pasture Consortium on February 7, and exploring options to present at the Vermont Organic Dairy Symposium.

• Will participate in the Organic Dairy and Field Crop Program Work Team of the NY Certified Organic Group on January 8th in Geneva, NY.

The major facilities accomplishment this year has involved intense interactions with a significant donor to the university, and, as a result of his generosity, further work with external consultants and University facilities personnel involved in the construction of an Aerobic Composting/Heat Recovery Facility. The new facility will be central to accomplishing research on the integrated wood-bedding-composting system described in the renewal proposal.

This successful fund-raising initiative will make available to this USDA SARE research project a $550,000 research and operations building that will enable testing of different methods of managing the production and application of bedding in the bedded-pack barns at the Farm, timing and management of manure/bedding removal and renewal, and timing, composition and management of composting for optimal heat production.

In addition to the construction of the facility, considerable research has been done on optimizing the full system, from bedding production to finished compost.

Following our initial findings on the various machines that produce animal bedding, we found that the most economical and best quality material came from shaving machines, and not chippers or grinders which can produce a biosawdust product for animal bedding purposes. This initial outcome led the research team to focus specifically on shaving machines and the construction of the on-farm animal bedding production model, which specifically allows a farmer to compare multiple shaving machines to their available budget and bedding needs. A polished version of this model will come out shortly. Resources in the form of USDA grant money were used to fund these initial findings, and the eventual publication of our results/model.

A second outcome originating from the preliminary data analysis on the model and eastern white pine stem analysis is that low-grade woody biomass that would normally be left in the forest, or made into chips for a wood-to-energy facility, has a higher value as shavings than traditional uses. The extra value as a small shaving log could potentially change the economics of many pine stands within the New England region, as low grade and small stems could turn a profit. These findings could allow for more intensive management, as pre-commercial harvests would become profitable. These initial findings have also led to conversations with local mills on the possibility of finding a higher value for their lower quality logs.

A final outcome generated from our initial data analysis has come from the design/build process for the heat-recovery composting facility. During this process, our research team carefully documented the various cost-reducing strategies we used, as we were intending on providing the information to the public once complete. Although the facility is still under construction, we have already been approached by a business intending on building a commercial-sized composting facility similar to the one being built at UNH. We are currently coordinating with this business, and providing detailed information and recommendations on the building process to save them cost. We also hope to form a partnership with this business, where we can provide them with the most up to date information on the type of compost technology we are both employing. As a research facility, we will be able to take the risks they cannot afford. Resources in the form of USDA grant money have helped support several aspects of this project, including the support of a graduate student who is working with the design/build team on developing a facility that is specifically geared for research experimentation.


Dr. Matt Davis

Associate professor
Univ. of New Hampshire
James Hall
Durham, NH 03824
Office Phone: 6038621718
Dr. Bill McDowell

James Hall
Durham, NH 03824
Office Phone: 6038622249