Which in-vessel system did we purchase?

We purchased a 2 ton in-vessel composting system from Wright Environmental Management Inc., a Canadian company.

About our compost expansion project

Ohio U. was recently awarded $1,088,571 through the American Recovery and Reinvestment Act to expand its compost project! The upcoming expansion will include the addition of: a 4-ton expandable in-vessel system, enabling the university to compost 100% of its pre- and post-consumer dining waste; a 31.1 killowatt solar array to completely power the current site and expansion; a 1.4 gallon solar thermal water heating system to improve the ability of workers to clean the collection bins with harvested rainwater; an industrial shredder, through which to process the biodegradable service ware, aiding in its breakdown; and a waste-oil burner to heat the pole barn which houses the composter for the comfort of workers during the winter. The expansion project is expected to be completed in 2011.

What do we do with the compost?

It takes a little over three months for the system to produce usable compost. Although the organic waste is processed in about 14 days, it needs to cure for another 90 days. The resulting nutrient-rich soil amendment is being used to improve intermural athletic fields and gardens used by Plant Biology students.
Click here to see a soil analysis of the compost.

What kind of biodegradable service ware do we use?

The University has been purchasing biodegradable service ware from Gordon Food Services and Nature Friendly. The bowls are made of sugar cane fiber that is a waste product of the sugar refining process. The cutlery is made from potato and other natural plant starches. The transparent clam shell containers are made from a biologically based polymer called PLA (polylactic acid), which is derived from corn or other plants. All of these items are manufactured by Stalk Market and Wilkinson Industries.
Concern has been raised, however, that these products are not breaking down fast enough to keep up with the composting system's cycle. The University began purchasing new service ware products from BioSelect, which appeared to break down more quickly in test batches. (Read more about Ohio University raising the bar on biodegradables.) However, even these are not performing as well as we would like. To fix the problem, Ohio U. will be adding an industrial shredder to its compost system, in order to give the service ware more surface area prior to being composted, hastening its breakdown.
Read more about the compost expansion project below.

How are we collecting the compost?

In our kitchens, we collect pre- and post-consumer waste in 64-gallon Schaefer bins on wheels. The compost bins came with the compost system and are compatible with the system's automatic arm lift. In order to keep the bins light enough for the lift to manage, we only partially fill the bins with food waste. Once the bins are loaded with food waste, they are rolled out to the loading dock.
In the public areas of our food court, patrons will be directed to sort their waste into trash, recycling and compost bins. This system was launched in January 2007 when the student center first opened. Early waste audits indicated that 75% of the compost waste stream contained little or no contaminants (chip bags, ketchup packets, and other non-biodegradable items). These bins, when full, will be rolled out to the loading dock by custodial staff. In our dining halls, post-consumer food waste will be collected by dining services employees. Students will continue to place their trays and waste onto the belts as they have always done.
Schaeffer bins
All the Schaefer bins are collected daily by the Grounds department and brought up to the compost site at the Ridges, overlooking the Athens campus. After being emptied into the system, the bins are power washed and returned to the dining facilities. We do not use biodegradable liners. (Bin image courtesy of Schaefer Systems International, Ltd.)
In order to help food court patrons and dining hall staff with the sorting process, we created a number of different educational posters which were displayed in both the dining hall kitchens and above the bins where patrons sort their waste.
Posters: Compostable Items What is Compost? Did You Know? All About Compost

Why did we choose an in-vessel system vs. windrows?

An in-vessel composting system will allow us to accelerate the decomposition process by controlling temperature, moisture, and aeration. Additionally, because the system is enclosed, all food waste (including meat and dairy) can be composted without fear of attracting rodents. Purchasing a system also enabled us to use a biofilter, which reduces odors at the site. Windrow and static pile systems require a relatively large area, long composting periods, and significant ongoing staff time. Further, they can present nuisance issues which limit siting options. The decision to use bio ware at the student center also significantly influenced our decision to purchase an in-vessel system. Although other schools have had success with breaking down bio ware in windrows, we wanted to ensure that our bio ware would break down quickly.

How will composting help Ohio U meet the Presidents Climate Commitment?

The system will be able to divert up to 25% of the Athens campus' current landfill waste. This diversion will result in an annual greenhouse gas emissions reduction of approximately 1,200 metric tons of carbon dioxide equivalents--about the same amount of CO2 emissions resulting from the energy use of 108 homes in one year.

Why did we go with Wright Environmental?

Wright Environmental has many operational systems in place in North America. As a university, we are required to go through a bidding process for any large purchase, and their system was competitively priced. The system allows for continuous loading and when the compost is removed from the system, it is ready to be used or spread on the grounds after the 90-day curing period. We preferred this over other systems which could not be loaded daily because the compost from these machines has to be unloaded from the system before new material can be added.

We also spoke with two other colleges and universities, St. Olaf College and Allegheny College, who are using Wright Environmental composting systems. Both institutions were pleased with the results of their units.

We seriously considered another system that would collect data remotely and allow us to monitor moisture, temperature and aeration from an office computer, but ultimately decided that this was an unnecessary feature for our operations since our grounds staff would be delivering compost to the site daily.

Wright Environmental Management, Inc.:
511 Woodland Acres Crescent Maple, Ontario
Canada L6A 3G2
(905) 881-3950 Phone
(905) 881-2334 Fax
Stephen Wright stephen.wright@wrightenvironmental.com

How much did the system cost?

Our in-vessel composting system cost $355,370.00. However, the total start-up costs associated with the project were more than twice that, or about $800,000.00. Some of the costs included a road upgrade, a cement pad, and a heated pole barn. The total cost also included bringing utilities to the site, creating a leach field, installing a 10 kWh solar array and installing a rainwater harvesting system.

How was the system funded?

Ohio University received $350,000 in grant funding from the Division of Recycling and Litter Prevention within the Ohio Department of Natural Resources. Funds were awarded through both the Market Development and College & University grant programs. We received an additional $35,105 for the solar array from the Department of Development's Energy Loan Fund grant program. The additional funding was provided through the operational budgets of two Ohio University departments: Facilities Management and Auxiliaries.

What Permits were needed?

EPA permits are required for all compost sites in Ohio. The permit required depends on the class of your compost site. If you need further guidance about EPA permits for compost sites in Ohio, please contact Angel Arroyo-Rodriguez at angel.arroyo-rodriguez@epa.state.oh.us, or
Joe Goichea at joe.goicochea@epa.state.oh.us.

What are the other "green" features of the site?

The site features a 10.03-kilowatt roof and ground mounted solar photovoltaic array. The array is grid-tied and was installed by Dovetail Solar & Wind of Athens. On average, the array meets 55% of the total energy demands of the facility. To date, it has generated 18,193 kWh of electricity. This is equivalent to emission savings of 12.5 tons of carbon dioxide that have been avoided due to the energy mix provided by the solar panels.
Harvested rainwater from the pole barn roof is used to maintain the system's moisture, as well as to clean the compost collection bins. After funneling through the down spout, the water travels to the roof wash, which removes leaves, twigs and other debris. The water is stored in a 2,200 gallon underground cistern and pumped into the system as needed.
The pole barn roof was built with daylighting panels to illuminate the space. The road to the site was paved using reclaimed asphalt from parking areas on campus that were demolished.

What are some of the challenges of the project?

Ohio University's student population is typically not one that is accustomed to composting prior to their arrival at the university. Since food court patrons are responsible for sorting their own waste at the student center, maintaining an uncontaminated organic waste stream may pose significant challenges.
In order to aid food court patrons in the sorting procedure we developed signs for the sorting areas. Our original signs were not compatible with dining hall aesthetics. So we needed to devise a way to communicate as clearly as possible in a way that complimented the food court's existing decor.
Purchasing bio ware is an additional challenge partially due to its expense. Also, it is debatable whether bio ware is actually sustainable. Our clear clam shell containers (used at the salad bar) are made of PLA which is derived from corn. Growing the corn and creating the PLA is a fuel intensive process. However, because people tend to insist on clear containers for their salads, we chose to go with the PLA salad containers. This way all of the service ware is biodegradable. Our hope is that this will simplify sorting procedures and aid in maintaining an uncontaminated waste stream.
Since the site is not connected to city sewer lines, leachate - or excess liquids - from the compost system was being collected in tanks and then pumped into a septic system. The EPA, who had first given the green light on this handling, has since taken issue with the substance permeating into the ground. The temporary solution has been to haul the tanks to campus where they are dumped into the city sewer lines.

Are there additional published resources about Ohio U.'s compost site?

Yes! Please note that although the project proposal states that we intended to purchase a 4.92 kW photovoltaic solar array, we ended up purchasing a 10.03 kW array. Furthermore, be cautious of using our exact budget figures, as several costs changed during the course of the project.

The National Wildlife Federation published a Campus Sustainability Case Study of Ohio U.'s in-vessel system in July of 2009. Read the report.

2007 Grant Proposal: Solar-Powered In-Vessel Compost Initiative, Ohio University

2007 Market Development Proposal: In-Vessel Compost Initiative, Ohio University

The Composting Project At Ohio University

In this video, Director of the Office of Sustainability Sonia Marcus narrates over images from the composter ribbon-cutting ceremony on February 12th, 2009. The video includes commentary from Chef Manager Eric Lee of the Central Foods Facility, and Greg King of the Grounds/Equipment Operations department at Ohio University.

When did the system begin operating?

We commissioned the machine at the end of January 2009 and it has been operating since then. A representative from Wright Environmental Inc. came and taught three members of our grounds crew to operate the machine.

The composter ribbon-cutting ceremony was held on February 12th, 2009. President Roderick McDavis and Director of the Office of Sustainability Sonia Marcus welcomed guests from around the region. Attendees from the Ohio Department of Natural Resources, the Ohio Board of Regents, and various political and governmental offices joined members of the Ohio University community to officially recognize the university's achievements in bringing this project to fruition.

How does the system work?

By controlling temperature, moisture, and aeration inside the machine, the in-vessel system accelerates waste decomposition, turning waste into soil in 14 days with no odors, no vector or pathogen control issues, and minimal staff involvement. After the waste is processed it must cure for an additional 90 days before it is ready to be used as a soil amendment.

What is being composted?

Currently we are composting food from our Central Foods Facility, Baker University Center, and Shively Dining Hall. When the food waste and bio ware are loaded into the in-vessel unit, they are amended with landscaping waste as well as animal bedding from research labs and sawdust from the carpentry shop, in order to achieve the right carbon to nitrogen balance.

What is the capacity of our compost system?

The system houses 14 trays, each with a capacity of two tons of organic waste. We are able to fill a maximum of one tray per day. Assuming that we do so, the material stays in the unit for 14 days and can be continuously loaded. During the school year we are at maximum capacity of the current system, which is 28 tons of material. This accounts for about 50% of our total food waste.

How much waste has been composted so far?

As of July 2010, Ohio U has composted over 263 tons of food waste and serviceware.

Take the tour.

For more information or to schedule a tour, please contact the Office of Sustainability.