If the services are indeed to use alternative fuels in tactical weapon systems, these fuels must be able to substitute for one or more of the three petroleum-based distillate fuels that currently support the majority of military operations: the two military jet fuels, JP-8 and JP-5 (“JP” stands for “jet propellant”), and naval distillate (F-76). From the perspective of technical viability, a number of alternative fuels can meet this requirement. But uncertainties remain regarding their commercial viability—namely, how much these fuels will cost and what impact they may have on the environment, particularly in terms of greenhouse gas emissions. Despite these unknowns, the Department of Defense is currently directing substantial resources—both dollars and personnel—to testing and certifying alternative fuels for use in tactical systems. The services, the Defense Advanced Research Projects Agency (DARPA), and the Defense Logistics Agency Energy (DLA Energy) are also sponsoring and conducting technology- development activities aimed at identifying advanced methods of producing alternative fuels.

—Alternative Fuels for Military Applications

In response to a congressional directive for a study on alternative and synthetic fuels, the US Department of Defense asked RAND to analyze whether alternative fuels can meet the needs of the nation’s military in a climate-friendly and affordable manner. RAND also was asked to examine the goals and progress of the efforts of the Army, Navy and Air Force in supporting the development of alternative fuel production technology, and in testing and certifying alternative fuels for military applications. Specific topics included:

• Opportunities to produce alternative fuels in a way that reduces lifecycle greenhouse gas emissions, including the use of clean energy alternatives such as nuclear, solar, and wind energies for powering the conversion processes.
• The military utility of concepts for production of alternative fuels in or close to the theater of military operations compared to domestic production.
• The goals and progress of research, testing, and certification efforts by the Department of Defense related to the use of alternative fuels in military vehicles and aircraft.
• The prospects for commercial production of nonpetroleum military fuels.

To analyze the efforts in the area of alternative fuels, the RAND team reviewed available documentation and technical reports; contacted key firms; and conducted in-depth interviews with representatives of DARPA, DLA Energy, and relevant organizations in each of the services.

The findings and recommendations presented in this report are those of the research team. In some cases, these findings conflict with views held and actions taken by the Department of Defense organizations involved in alternative fuel research, testing, and certification.

—Alternative Fuels for Military Applications

Major topics of the report include: Opportunities to Produce Alternative Fuels with Lower Greenhouse Gas Emissions; The Military Utility of Forward-Based Alternative Fuel Production; Goals and Progress of the Military Departments; and The Prospects for Commercial Production.

Opportunities to Produce Alternative Fuels with Lower Greenhouse Gas Emissions. The study concluded that Fischer-Tropsch (FT) fuels are the most promising near-term options for meeting the Department of Defense’s needs cleanly and affordably. If FT fuel production is to occur without compromising national goals to control greenhouse gas emissions, however, the following must hold, according to the report:

• For biomass-derived FT fuels, the biomass feedstock must be produced in a sustainable manner; specifically, its production should not be based on practices that lead to sizable emissions due to direct or indirect changes in land use. If this is achieved, lifecycle greenhouse gas emissions can be near zero.

• For coal-derived FT fuels, carbon dioxide emissions at the FT fuel production facility must be captured and sequestered. If this is achieved, lifecycle emissions can be in line with those of petroleum-derived fuels.

• For FT fuels derived from a mixture of coal and biomass, carbon dioxide capture and sequestration must be implemented. The biomass must also be produced in a sustainable manner. If this is achieved, lifecycle emissions can be less than half those of petroleum-derived fuels. In particular, a feedstock consisting of a 60/40 coal/biomass blend (by energy) should yield alternative fuels with lifecycle greenhouse gas emissions that are close to zero.

Considering economics, technical readiness, greenhouse gas emissions, and general environmental concerns, FT fuels derived from a mixture of coal and biomass represent the most promising approach to producing amounts of alternative fuels that can meet military, as well as appreciable levels of civilian, needs by 2030. But whether this technology will reach its potential depends crucially on gaining early production experience—including production with carbon capture and sequestration—in the United States. At present, no agency of the US government has announced plans to promote early commercial use of FT fuels derived from a mixture of coal and biomass.

—Alternative Fuels for Military Applications

Other conclusions in this area are:

• It is highly uncertain whether appreciable amounts of hydrotreated renewable oils can be affordably and cleanly produced within the United States or abroad. Hydrotreated renewable oils are produced by processing animal fats or vegetable oils (from seed-bearing plants such as soybeans, jatropha, or camelina) with hydrogen. Various types of algae have high oil content and are another possible source of oil for hydrotreatment. Fifty-fifty blends of hydrotreated oils have already been successfully demonstrated in flight tests sponsored by the commercial aviation industry. Laboratory analyses and testing strongly suggest that hydrotreated renewable oils can also be formulated for use in the Department of Defense’s tactical weapon systems. Technical viability is not an issue, the authors emphasized.

  Considering (1) the very limited production potential for fuels derived from animal fats and waste oils, (2) the highly uncertain prospects for affordable, low greenhouse- gas fuels derived from seed crops, and (3) the early development status of algae-based concepts, hydrotreated renewable oils do not constitute a credible, climate-friendly option for meeting an appreciable fraction of military fuel needs over the next decade. Because of limited production potential, fuels derived from animal fats, waste oils, and seed oils will never have a significant role in the larger domestic commercial marketplace. Algae-derived fuels might, but technology development challenges suggest that algae-derived fuels will not constitute an important fraction of the commercial fuel market until well beyond the next decade.

  —Alternative Fuels for Military Applications

• Nuclear, solar, and wind energy technologies may offer important benefits in the production of military, as well as civilian, alternative fuels. Nuclear, wind, and solar energy offer electric power without emitting appreciable amounts of greenhouse gases. For the near- and mid-term alternative fuel options (i.e., hydrotreated oil from animal fats and vegetable oils, and FT liquids), electric power is not an important input to the production process, but hydrogen is. If sufficient hydrogen is available, nearly all of the carbon in the coal or biomass feedstock to a Fischer-Tropsch plant would end up in the fuel products and not in the air, eliminating the need to capture and sequester carbon dioxide, the authors said. In addition, the use of hydrogen in an FT plant could nearly triple yields of liquid fuels.

  For hydrotreated oil from algae, a longer-term option, climate-friendly sources of electric power could be used directly in the processes of cultivating the algae and extracting the oil, because electricity is required for mixing, circulation, and management of water and nutrients.

  —Alternative Fuels for Military Applications

• The beneficial hydrogen derived from nuclear, solar, and wind energy technologies is not an economically viable option over the near- to mid-term.

The Military Utility of Forward-Based Alternative Fuel Production. Concepts for forward-based alternative fuel production do not offer a military advantage, the authors find. Although concepts have been proposed for alternative production systems—including position in forward operating bases, floating platforms, and small-scale units co-located with tactical units—all of these have logistical or cost barriers, according to the study.

In short, traditional systems, in which fuel is produced outside the theater and then shipped in, continue to be the most practical in terms of military utility.

—Alternative Fuels for Military Applications

Goals and Progress of the Military Departments. Defense Department goals for alternative fuels in tactical weapon systems should be based on potential national benefits, since the use of alternative, rather than petroleum-derived, fuels offers no direct military benefits, according to the report.

...there are nationally important benefits to be gained from the use of alternative fuels. If the Department of Defense were to encourage early production experience, government decision makers, technology developers, and investors would obtain important information about the technical, financial, and environmental performance of various alternative fuel options. If favorable, that information could lead to a commercial alternative-fuels industry producing strategically significant amounts of fuel in the United States. Once established, a large, commercially competitive alternative fuel industry in the United States and abroad would weaken the ability of the Organization of the Petroleum Exporting Countries to assert its cartel power. Lower world oil prices would yield economic benefits to all fuel users—civilian and military alike. Lower prices would also decrease the incomes of “rogue” oil producers, and thereby likely decrease financial support to large terrorist organizations such as Hamas and Hizballah.

—Alternative Fuels for Military Applications

The study found that current efforts by the services to test and certify alternative fuels are “far outpacing” commercial development. Given where industry is in the process of developing these fuels, the authors said, some of these efforts—at least at the current levels of funding and personnel—may be premature.

Should the Department of Defense continue to support the development of technology to produce alternative fuels, it should consider consolidating and strengthening management and shifting support to longer-term goals, the report said. Finally, the authors noted, to cost-effectively promote early industrial production of alternative fuels, the Department of Defense needs extended contracting authority for fuel purchases.

The Prospects for Commercial Production. Overall, the RAND team concluded, within the United States, the prospects for commercial production of alternative fuels that have military applications remain highly uncertain, especially over the next decade.

Specific recommendations include:

• The Department of Defense should complete testing and certification of Fischer-Tropsch liquids for use in 50/50 fuel blends, but testing at higher concentrations is not appropriate considering the very limited commercial production anticipated over at least the next decade.

• Minimize resources directed at testing and certification of hydrotreated renewable oils, including oils derived from seed crops (e.g., camelina) and algae. Testing and certifying these fuels in high-performance propulsion systems used by the military is simply not on the critical path for resolving the uncertainties associated with these fuels.

• Considering the absence of military benefits, the Department of Defense and Congress should reconsider whether defense appropriations should continue to support the development of advanced alternative fuel technologies.

• If the Department of Defense is to continue to support alternative fuels, its role and the Department of Energy’s role need to be clarified.

• For technical, logistical and security reasons, research directed at advanced concepts for forward-based production of energy should focus on electric power as opposed to specification-grade military fuels for use in weapon systems.

The RAND investigation was limited to alternative fuels, as opposed to the whole of energy use across the Department of Defense. But this study can be placed within the broader context of an overall energy strategy for the US military. The RAND team’s finding that the use of alternative fuels offers the armed services no direct military benefit is consistent with top-level findings of recent studies on military energy issues by the Def est served by efforts directed at using energy more efficiently in weapon systems and at military installations. In this regard, the services’ energy programs are clearly, and appropriately, placing the greatest emphasis on measures that would increase the efficiency of energy use.

—Alternative Fuels for Military Applications

Research for this report was sponsored by the Defense Logistics Agency-Energy and was conducted within the Acquisition and Technology Policy Center of the RAND National Defense Research Institute, a federally funded research and development center sponsored by the Office of the Secretary of Defense, the Joint Staff, the Unified Combatant Commands, the Navy, the Marine Corps, the defense agencies, and the defense Intelligence Community.

Resources

• James T. Bartis, Lawrence Van Bibbe (2011) Alternative Fuels for Military Applications