EXECUTIVE SUMMARY PROCESS AND SITE SELECTION

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1 EXECUTIVE SUMMARY The Cornell University Renewable Bioenergy Initiative (CURBI) was developed by a team under the direction of Michael Hoffmann, Director, and Drew Lewis, Director of Operations, of the Cornell University Agricultural Experiment Station, with the goal of reducing campus greenhouse gas (GHG) emissions and identifying beneficial uses for approximately 30,000 tons per year of biomass produced within Cornell University. While the initial objectives of the CURBI study were to identify renewable energy technologies which would reduce the University s dependence on fossil fuels and improve its carbon footprint, it has become apparent that the primary benefit of the CURBI project could be to establish a renewable energy platform which could be used to further teaching and research and extension outreach activities related to GHG reduction and renewable energy production from biomass. Cornell University, being a major agricultural research center, produces a wide variety of organic feedstocks ranging from woody biomass to liquid manure and alkaline hydrolysate waste from the Veterinary College. For this feasibility study, only biomass materials available within a 25-mile radius of the CURBI site were considered, although it would be possible to increase the scale of the facility in the future. The CURBI processes were selected to allow a wide variety of feedstocks to be converted to bioenergy. The purpose of this study was to evaluate the technical, economic, environmental, operational, and community feasibility of constructing and operating the CURBI research facility. PROCESS AND SITE SELECTION Many bioenergy processes were evaluated for inclusion in the CURBI facility, with the following being selected: Direct combustion Anaerobic digestion Dry fermentation Pyrolysis / torrefaction Biodiesel conversion ES-1

2 Of these, direct combustion, anaerobic digestion and biodiesel conversion are well proven technologies in the United States. Dry fermentation and pyrolysis/torrefaction have been proven in Germany, Australia, and South Africa, among other countries, but have yet to be widely used in North America. All processes offer many research opportunities. Cogeneration is a beneficial process for many bioenergy facilities and could provide similar benefits for the CURBI system. Beneficial uses for waste heat produced by processes from biogas generators or boilers must be found in order to improve the cost effectiveness of the overall processes, and the proximity of these host facilities is an important cost factor. Proximity to major process feedstocks is also advantageous.. Based on these and other factors, it was determined that the most favorable location for the CURBI facility would be on the Game Farm Road site south of Route 366, adjacent to the current agricultural waste laboratory and a proposed Cornell College of Agriculture and Life Sciences dairy facility, the Large Animal Research and Teaching Unit (LARTU). TECHNICAL FEASIBILITY Five alternate technologies were considered for conversion of biomass to energy. Anaerobic digestion, dry anaerobic fermentation, direct combustion, pyrolysis, and biodiesel conversion were all determined to be applicable processes and are technically feasible for the CURBI project. These processes are synergistic in that heat and by-products from several of the processes can be used to facilitate treatment in other processes. The technical analysis indicates that all of the available biomass feedstocks can be converted to energy using one or more of these identified processes. Beneficial by-products include heat and electricity, digestate for land application or composting, and biochar or biochar mineral complex (BMC) for carbon sequestration and soil stabilization. Of the identified bioenergy processes, direct combustion, anaerobic digestion, and biodiesel conversion could be implemented with a high probability of successful operation due to previous experience on hundreds of similar projects. Pyrolysis/torrefaction and dry fermentation have not been demonstrated in full-scale operations in North America, and therefore should be considered as developing technologies, with some risk of process failure. Conversely, these technologies also offer the greatest opportunities for research and development and remain technically feasible ES-2

3 While it was necessary to assume specific technologies to analyze the costs and benefits of this facility, it was also recognized that other compatible technologies may have benefits both for research and as practical additions to Cornell s future low carbon plans. For example, Cornell s Climate Action Plan (CAP) proposes a future large-scale biogas production facility, which could benefit greatly from scaled testing at the facility. While this and other potential processes are not analyzed in detail in this report, the CURBI facility would also be appropriate for the testing or multiple new and emerging technologies moving forward, all of which could utilize the essential biomass processing, storage, and feed systems, as well as the energy (heat and electric) conversion and distribution systems. Although the system as presented would be an integrated system utilizing the synergies of the alternate biomass-to-energy processes, it would be possible to phase installation of the CURBI system, depending on funding availability and research needs. It is proposed that the anaerobic digester and dry fermentation units be co-located near a common mechanical room and electrical room, using a combined biogas treatment and energy generation system. Separately, the direct combustion and pyrolysis technologies could be implemented to produce biochar and biochar mineral complex for additional research with soil science and carbon sequestration applications. SITE SELECTION It was determined that the most economically feasible location for the CURBI facilities would be at the Game Farm Road site located in the Farm Services area south of Route 366. Careful consideration was also given to the Stevenson Road location, which is currently used for grain drying, crop production, and composting of Cornell s waste biomass. Implementation of the CURBI system at the Stevenson Road location would be less cost effective, even if the capital costs are covered by outside funding. While the Stevenson Road site offers many advantages including traffic access, minimal potential nuisance issues, adequate space, and ability to expand in the future, the site does not currently have year-round uses for the electricity and heat produced by the CURBI process. Electricity could be sold to New York State Electric & Gas, but only at the wholesale rate. The use of excess heat produced by the CURBI facilities to dry grain on a seasonal basis was determined to not be cost effective compared with propane, whereas the Game Farm Road site offers several operations for year-round use of the electricity and thermal energy produced by the CURBI processes. In the future, if additional buildings or greenhouses were co-located on the CURBI site, full advantage could be taken from the excess heat produced by the biomass-to-energy processes ES-3

4 ECONOMIC FEASIBILITY The estimated cost of construction of the CURBI system as proposed is approximately $9,300,000, with estimated annual operation and maintenance costs of approximately $500,000. These cost estimates include conservative contingencies for consideration of the additional instrumentation and control systems, and operational complexity associated with operation of a research grade facility. The CURBI facility would create both direct and indirect economic benefits. These benefits include the value of created energy streams, the value of agricultural and research by-products of the processes, and the value of the resulting research, education, and outreach. When taken together, these benefits create a positive economic performance. Potential economic benefits of the CURBI system result from production of electricity and thermal energy, which could partially offset the use of fossil fuels. Preliminary calculations indicate that over 2,600 megawatt hours of electricity and 29,000 MMBtu of thermal energy could be produced by CURBI, with an estimated value of over $1 million per year, compared with conventional services. If torrefaction is used to create biochar mineral complex, the potential usable thermal energy drops by 75 percent; therefore, the most logical time to produce BMC would be during the summer months when heating needs are low. By-products produced by CURBI also add value. The most apparent benefit produced by CURBI would be the production of 2,600 tons/year of biochar, with an estimated value of $1,260,000. This report does not quantify the value of research, education, or outreach, which are difficult to quantify in advance of research and outreach success. Therefore, the financial performance tables included in this report do not include any value for these attributes. However, this benefit is arguably the most valuable for Cornell and the State given the shared goal of promoting local agricultural resource development, jobs development, and technological base together with the shared desire to reduce impacts on fossil fuel use. Similarly, the value of helping solve the environmental challenges posed by GHG emissions and future fossil fuel scarcity is also not quantified. Again, it could be argued that this potential alone justifies the value of this research proposal ES-4

5 Incorporating only the fuel cost savings and by-products value, with the CURBI facility located on the Game Farm Road site where it could provide beneficial electricity and heat to Cornell s facilities, the project nearly recovers all costs, including amortized capital costs. If the capital costs of the facility are paid for by grants, donations, or other funding sources, the sustainable cost results in a positive cash flow of over $850,000 per year. In addition, operation of the CURBI facility could be a catalyst to attract research funding which could help subsidize the ongoing costs of the system. ENVIRONMENTAL FEASIBILITY At both the Game Farm Road and the Stevenson Road sites, it was determined that the CURBI facilities could be environmentally feasible, and that issues of wastewater discharge, stormwater discharge, air emissions, and solid waste production could be effectively mitigated through conventional means. One advantage of the integrated CURBI system is that nearly all solid and liquid by-products from the CURBI system have some beneficial use for agricultural application. A significant environmental benefit of CURBI is the potential reduction of the University s carbon footprint by nearly 10,000 metric tons of carbon dioxide equivalent per year. Over half of this reduction results from carbon sequestration by biochar, with the remaining reduction resulting from offsetting fossil fuel consumption through beneficial use of bioenergy. More importantly, as the New York State Land Grant institution, the potential reduction in GHG emissions that could result from the success of Cornell s research and outreach associated with the facility could dwarf Cornell s own emissions savings. A key advantage of the proposed CURBI system is that virtually no wastes are produced which would require disposal at a landfill. Most of the solid and liquid byproducts would be applied to cropland as fertilizer and soil amendment. OPERATIONAL FEASIBILITY The CURBI integrated system was determined to be operationally feasible, and it is estimated that a full-time staff of two to three skilled workers could operate the materials handling and process operations functions of the system. It is anticipated that forest biomass would be chipped off site and transported to the CURBI site to minimize on-site labor requirements. Regional ES-5

6 biomass processing is already being proposed by the Ithaca community, which hopes to include Cornell as a key user of this resource. Onsite operational activities range from loading and unloading and storing biomass feedstocks, to monitoring and adjusting control systems, to operating electrical and hydronic systems. A high degree of responsibility is required for workers who would be exposed to hazards from heat, electricity, and explosive gases. COMMUNITY FEASIBILITY A review of the operational requirements for the CURBI system indicates that it would be similar in community concerns to a commercial farming operation. Truck and tractor traffic, dust, noise, and odors are potential nuisance factors which should be addressed in the design phase to mitigate community concerns. In concept, the objectives of the CURBI system represent a positive contribution to the community through renewable energy production, technology outreach, carbon footprint reduction, and beneficial use of waste materials. While it is difficult to predict the full level of public support for a green renewable energy research facility such as the CURBI integrated system, a preliminary review of potential community concerns indicates that both the Game Farm Road and Stevenson Road sites present a minimum number of potential nuisance issues, and that the CURBI operations would coincide with traditional rural agricultural activities. Design features such as containment pads for unloading of feedstock and use of an organic biofilter to control odors from the anaerobic treatment complex would minimize potential stormwater and odor issues in the vicinity of the CURBI project. The feasibility study includes identification of a proposed permit strategy which implicitly recognizes the importance of obtaining public support for the project. CONCLUSIONS In this study, it has been determined that the CURBI integrated system project provides a host of benefits to Cornell, the surrounding community, and broader society and could be feasible in all areas with sufficient additional funding from private, state, or federal sources. Potential funding avenues include the New York State Energy Research & Development Authority (NYSERDA), ES-6

7 the U.S. Department of Energy, the U.S. Department of Agriculture, and distribution of renewable energy funds from the Regional Greenhouse Gas Initiative (RGGI). The Cornell University CURBI facility would be among the first of its kind in the world, where alternate technologies are available on the same site for comparative research into effectiveness of various biomass-to-energy processes using common feedstocks. Cornell s position as a leading agricultural research facility, combined with the strength of its engineering programs, offers a unique opportunity to create a world class renewable biomass-to-energy research facility. BIOCHEMICAL CONVERSION ANAEROBIC DIGESTION DRY FERMENTATION Purpose: Produce biogas, reduce odors Produce biogas, reduce odors TYPE QUANTITY TYPE QUANTITY Raw feedstock Manure, hydrolysate 8,000 tons/yr Manure, plants 13,400 tons/yr Biogas production Annual yield 9 MM ft 3/yr Annual yield 105 MM ft 3/yr Liquid byproduct Liquid effluent 5,800 tons/yr N/A N/A Solid byproduct Separated solids 1,400 tons/yr Digestate/pyrolysis 12,100 tons/yr Byproduct use/ disposal Fertilizer / compost / pyrolysis Compost 6,720 tons/yr Biogas energy Biogas to CHP 217 kw Biogas to CHP 1,580 kw content Net energy Heat/electricity 97 kw Heat/electricity 872 kw produced Carbon offsets Energy offset 414 mtco 2 e/yr Energy offset 3,070 mtco 2 e/yr Considers eight months per year that thermal energy can be used. THERMOCHEMICAL CONVERSION DIRECT COMBUSTION PYROLYSIS (WITH TORREFACTION) Purpose: Supply heat to feedstock dryer Produce biochar, carbon sequestration TYPE QUANTITY TYPE QUANTITY Raw feedstock Straw 825 tons/yr Manure, plants 8,720 tons/yr Byproduct Ash 12 tons/yr Biochar 2,800 tons/yr Byproduct use/disposal Landfill application of ash Soil amendment / carbon sequestration Net energy produced Heat 634 kw Heat 1,400 kw Carbon offsets Energy offset N/A Energy offset 1,000 mtco 2 e/yr Carbon sequestered N/A N/A Biochar 5,320 mtco 2 e/yr Considers eight months per year that thermal energy can be used ES-7