The focus of this project is to design, build, and operate a modular SFP to convert natural gas, via FT and hydroprocessing reactions, into hydrogen-saturated diesel fuels and to test those fuels in various types of engines. The SFP was designed and built to be modular and mobile so it can be moved and easily modified to take advantage of diverse feedstocks. The plant is built to take advantage of future environmental economic incentives by reducing vented natural gas and using it as a feedstock. Carbon dioxide emissions also are reduced by simultaneously sequestering the CO2 and using it for enhanced oil recovery.
The SFP diesel fuel was tested in a variety of engines and vehicles to ensure that use of the product results in acceptable compatibility with fuel injection system components and improved emissions. The SFP diesel fuel was also tested to demonstrate compatibility with exhaust-after-treatment emission control systems.
The WMATA and Denali National Park bus fleets were chosen to evaluate SFP fuels because they represent nearly opposite ends of several spectra, including climate, topography, engine load factor, mean distance between stops, and composition of locally used conventional diesel fuel. Also, the managers of these fleets share the strong desire to participate in a program aimed at minimizing exhaust emissions, especially those emissions that are most apparent to riders, people in other vehicles, and bystanders.
The final stage of the project has been to perform an economic analysis on the data obtained from the project to predict commercial viability of the fuel and SFP process, including within the remote areas of Alaska, where the logistics of supplying conventional petroleum-derived diesel fuel can be extremely challenging. Fuel test data and cost data, derived in part from construction and operation of the Syntroleum SFP, have been used to develop a well-to-wheels economic analysis. The economic analysis includes likely market thresholds for an eventual substitution of synthesis gas-derived ultraclean fuels for conventional fuels. While already attractive from an environmental perspective, these ultraclean fuels also are expected to become more economically competitive. Conventional fuels are increasingly derived from “sour” crudes that are more costly to refine. Since U.S. oil needs are projected to rise, and refining costs are increasing, the market price of fuel is expected to continue to climb.
A modular SFP GTL plant was constructed, and an ultraclean, near-zero-sulfur diesel fuel was produced for fleet testing in Denali National Park and Washington, as well as in stationary engines in rural Alaska. Fuel test data and cost of production of the fuel were evaluated as well as demonstration of the fuel's practicality in commercial settings.
Among the project's milestones:
- An SFP pilot was dedicated in October 2003.
- The first fuel was shipped from the plant in April 2004.
- Fleet testing in Denali National Park was carried out during the summer of 2004. When planned testing was completed at the end of the park's summer season, the park asked to extend the testing into the winter months.
- Fleet testing in Washington started in September 2004 and was completed in April 2005.
- Fuel testing in a stationary diesel generator, sized to supply power for more than 50 homes, started in August 2004 and was completed in February 2005.
- Dynamometer testing was completed in March 2005.
- Fuel production was completed in March 2005.
- The well-to-wheels efficiency and economics analyses, including information specific to Alaska, were completed in February 2006.