ARF06 - Technical and Economic Analysis of Alternative Processes for Agricultural Waste Fueled Solid Oxide Fuel Cell

| Alternative Renewable Fuels - Project Summaries 2004 |

Researcher:

Dr. Kunal Karan, Dept. of Chemical Engineering, Queen's University

Objectives:

1. Develop and analyze process designs for conversion of agricultural waste to fuel gas produced by Anaerobic Digestion compatible with a solid oxide fuel cell (SOFC).
   
2. Determine process efficiencies and power generating capacity for the selected
   process design.
   
3. Develop cost model for the selected process design.
   
4. Assess the commercial viability of the process for a future field demonstration
   study.

Expected Benefits:

1. Identity of the most commercially viable process configuration for an agricultural-waste fueled fuel-cell power systems for a future field demonstration of a 5 kW Fuel Cell Technologies Ltd. SOFC (solid oxide fuel cell) system.

Summary of Research Results:

This project investigated the technical and economic factors that determine the potential feasibility of a biogas fuelled solid oxide fuel cell (SOFC). The choices of anaerobic digestion (AD) technology as well as the options for gas cleaning are investigated, and some determination of appropriate and viable alternatives for differing circumstance and application is offered.

Anaerobic digestion and fuel cells are complementary technologies that have, together, a compelling set of advantages in terms of odour reduction, emission reduction, pathogen reduction, fertiliser improvement, noise reduction, electrical and heat generation capabilities and efficiencies, and reliability. At present, the cost of SOFC power generation equipment is prohibitive, and cannot compete on cost with the incumbent technology, which is a modified diesel genset. Whilst there are other technologies such as microturbines being investigated and employed for combined heat and power in the agriculture industry, there has been some difficulty in the robustness and investment level.

The SOFC coupled with an AD system can be economically feasible under certain conditions, even without quantifying all of the benefits listed above. Should the SOFC cost reduce to a level competitive with the modified diesel genset, a communal site processing manure from 800 head of dairy cattle can provide a positive NPV of the cost savings and investment requirement over the reasonable life (10 years) of the facility. Similarly, a positive NPV could also be attained should the electricity price realised in the analysis increase to $0.11/kWhr.

It is further recommended that a practical trial be designed and undertaken, so that more data can be gleaned regarding the less readily quantifiable benefits, as listed above, to the employment of SOFC power generation in conjunction with AD production of biogas.