Geerlings Hillside Farms

» See our response to public comments on this project

Geerlings Hillside Farms is the first centralized digester project in the state of Michigan. The project will benefit climate change strategies by reducing the amount of greenhouse gases produced in piggery operations, as well as reducing the greenhouse gases from the facilities’ electricity use by displacing fossil fuel based power with clean renewable power.

The project is not yet operational. Construction is expected to be complete in March, 2008.

Currently, the manure on this 8,000 swine facility is stored for months under the swine barns and then trucked to fields where it is applied as fertilizer. While in storage, the manure decomposes anaerobically and results in large amounts of methane. Methane is a harmful greenhouse gas. When the project is operational, manure will be fed directly into a large tank to capture the methane and use it for energy production.

TerraPass funds would help ensure an adequate financial return for the project and satisfy the expectation project developers had about the voluntary carbon market supporting the project. TerraPass would be the only entity to purchase any credits from the facility and is planning to purchase them under a long-term contract.

The project is innovative, as ordinarily digesters on small facilities like Geerlings Hillside can’t cover their costs due to minimal electricity savings. But by arranging for manure from other farms (already being hauled away) to come to the digester, additional electricity will be generated for use onsite. With these additional electricity savings and with the carbon revenues, the project is economical.

This project will be third-party validated and then verified according to the Voluntary Carbon Standard 2007. The United Nations’ Clean Development Mechanism calculation methodology for agricultural methane — “ACM0010” — will be used to quantify the carbon credits.

Project details

The “Geerlings Hillside Farms: Methane Recovery & Electricity Generation Project” (hereafter, the “Project” or “GHF-O”) is a complete mix mesophilic anaerobic digestion treatment facility to recover methane gas, produce electricity from this gas and demonstrate and develop innovative treatment technologies for the reduction of the nutrient content of the waste stream from several local animal feeding operations through the use of a nutrient recovery system.

The project treats raw manure and wastewater from 8,000 breeder swine onsite by anaerobic digestion, replacing the farm’s manure management practice of under-floor storage, followed by trucking and field application. Under-floor storage time was several months and capacity existed for up to a year of storage.

The site also plans on recovering manure from four other facilities: Meadowbrook Farms (swine, 1 mile), Hogquest, LLC (swine, 1.5 miles), Carl Meyer Farms (swine, 2 miles), and Scenic View Dairy — Zeeland (heifers, 6 miles). These farms will contribute a minimum of 1.6M gallons and a maximum of 6.2M gallons, for a total of over 8M gallons of manure per year.

Onsite manure previously stored in pits under the barn housing will be pumped continuously to the digester. Other farms’ manure will be delivered in closed trailers and loaded into the digester at the time of delivery.

One 65-foot diameter, 550,000-gallon insulated digester tank with multiple agitators is lined with a dual impermeable membrane that isolates the system from oxygen and captures the biogas. A hydraulic retention time of 28 days is expected.

The biogas from the digester will then used for the production of electricity and to run a small boiler for on-farm use. Waste heat from the generators will heat the digesters to mesophilic temperatures (98°F to 104°F) and will also be used in biofiber drying.

The nutrient recovery system is an innovative use of the solids to avoid local environmental concerns with soil application (the local soils are phosphorous over-loaded). By implementing a Closed System Nutrient Recovery Cell (CSNRC), nutrient rich and valuable solids can be removed from the effluent, pelletized and sold as fertilizer for use in areas with normal phosphorous loads. In addition, the manure supply agreements with neighboring farms contain an option for contributing farms to obtain liquid digestate for use on local fields during crop cultivation periods. The final liquid effluent from the process will be pumped into a 1.5 million gallon tank and field applied as irrigation water, replacing water previously taken from the Little Rabbit watershed.

Two I-Power 65kw gensets had been delivered at the time of our site visit. These are integrated units and provide 3-phase power to the site, avoiding the need for grid interconnection or upgrade. The generators’ capacity is sized to have adequate capacity for summer farm needs of 115kw (winter farm needs are closer to 50kw).

Our model shows that biogas flow rates will be insufficient to power both engines at capacity, with closer to 100kw being a more realistic figure, unless more waste is added to the system.

An open flare has been installed to combust any excess methane gas not used by the generators.

Development of the Project reduces greenhouse gas emissions produced by the release of methane from the under-floor waste storage, and further reduces greenhouse gas emissions by displacing local grid electricity used onsite with renewable electricity generated onsite.

Project location

The project is located in Overisel, in southwest lower Michigan, about 30 miles from Grand Rapids.

Other environmental and social benefits

Environmental benefits

• Improvement in air quality (e.g., VOC reductions)
• Elimination of odor in surrounding areas, improving living standards on the farm and in the neighboring communities, and in the areas where manure is field applied Reduced use of trucking fleets to ship manure to far away locations, balanced with increased trucking of manure to a central facility.
• Reduced water use through the nutrient removal system.
• Instead of drawing water from the local watershed, the effluent is low enough in nutrients to be field applied. Installation of a nutrient recovery system could enhance local soil management

Social benefits

• Local employment for construction related to the project, installation of equipment, and operation of the Project
• Increasing energy independence for the farming sector. * * This manifests itself both in longer term low energy costs (extending beyond the crediting period) as well as reduced exposure to price risks in energy markets. Continued operation of a family-owned dairy farm by improving its economic positioning.

Project’s ability to foster further greenhouse gas emissions reductions

• Development priming: this is the first multi-farm digester in the state, and brings digester technology down to a farm size that currently wasn’t accessing it. The innovative nutrient recovery system is already being replicated at a follow-on project at a nearby facility.

Discussion of appropriate use of TerraPass funds

The project is an ideal candidate for TerraPass funds as carbon revenues clearly were a decisive factor in helping this path-breaking project that will significantly and permanently reduce greenhouse emissions, achieve a modest financial return.

TerraPass considers many aspects of projects before deciding whether to fund them. Here is a summary of key considerations for this project.

Baseline conditions

Before the installation of a digester, the management of Geerlings Hillside Farms managed manure much like many other piggery operations in the US — prior to field application, manure was stored under the barns for several months where it slowly decomposed. The soluble manure, or “volatile solids” in the under-floor storage decomposes under anaerobic conditions, which leads to large emissions of methane, a harmful greenhouse gas about 21 times as damaging than CO2.

Additionality

No regulatory requirements. There are no state, federal, or local regulations requiring the piggery to manage its manure in this manner.

US-based anaerobic digester projects are widely accepted as additional by analysis of their aggregate economics and adoption profiles. As of the November 2007, there were approximately 16 dairy digesters in operation in the USA, out of a total of about 79,000 piggeries.

This project meets the eligibility criteria of all the following performance standard protocols: EPA Climate Leaders, California Climate Action Registry, and CCX Offset Protocol. The project will be validated and then verified against the Voluntary Carbon Standard 2007, following the Clean Development Mechanism’s ACM0010 as the approved methodology.¹

Barriers to Implementation. This project is the first digester in Michigan to undertake centralized collection of waste and one of three digesters in the state of Michigan; as such it faced early farm coordination, market and technology barriers. Other alternatives open to the facility, such as continuing under-floor storage and field application, were not prevented by these barriers. We have not been made aware of any reasons that continuing operations would face any regulatory barriers.

Impact of TerraPass funds. A review of the project’s economic modeling at the time of construction showed clear expected carbon offset revenues, and the magnitude of carbon offset revenues significantly contributes to making the project economically feasible for the facility owner compared with other investment alternatives. The project is not yet operational, but the long-term contract planned by TerraPass delivers on the expectation of carbon revenues.

Better than most. TerraPass seeks projects where the operations have shown good practices and avoided substantial negative impacts. Geerlings Hillside is a well run piggery with good community relations. By bringing centralized manure management locally, the farm is establishing a new model for smaller farms to attain energy independence and manage waste streams. The project’s work toward an innovative nutrient recovery system has already led to follow-on project at a neighboring dairy and will significantly reduce water use in a key watershed area.

Footnotes

1. Installed systems from AgStar Anaerobic Digester Database. Total facilities from Climate Leaders Draft Offset Protocol, October 2006.