CLIESEL FUEL INC., FLORIDA, USA

EXECUTIVE SUMMARY

Petroleum-based fuels and related materials are central to the economies of developed and developing countries around the world. However, these resources are finite and expected to enter a period of diminishing availability within the next several decades.

To move economies based on petroleum and its feedstocks to fuels and materials that are renewable, environmentally friendly, and of greater availability, the science and engineering communities worldwide are exploring many options. Principal alternative energy resources that scientists have been exploring are wind, solar radiation, hydropower, geothermal power, coal combined with carbon sequestration, hydrogen, and biomass. In addition, biomass and biologically-generated polymers are attractive renewable feedstocks as energy-producing materials. It appears likely that no single resource will offer the versatility of petroleum in the future.
 As a result, several complementary technologies are being explored to meet the world’s diverse needs for energy and resource materials. Biologically based transformations have several potentially favorable attributes. They typically operate on renewable resources, at low temperatures, in aqueous environments, and produce few byproducts because of the specific nature of enzymatic catalysis.
 
These attributes make industrial biotechnology inherently consistent with the principles of Green Chemistry and promise industrial commodity production with less environmental impact. In this document, the application of industrial biotechnology to the important commodity classes of fuels and plastics is reviewed. Where applicable, those areas that have been advanced under funding from the joint EPA and National Science Foundation (NSF) program, Technology for a Sustainable Environment (TSE), are highlighted. Promising areas for future exploration and development are identified as well.

A. BIOMATERIALS

The worldwide production of plastics reached 260 billion pounds per year at the end of the 20th century, with a value of over $310 billion to the U.S. economy in 2002. Approximately one-third of all plastics produced are intended as disposable packaging, and nearly all these plastics are derived from petroleum and are highly resistant to natural biodegradation. Because plastic is recycled at rates of only a few percent in most countries, plastics are rapidly accumulating in unproductive and virtually permanent landfills. Additionally, pollution results from the manufacture, use, and disposal of plastic materials.

Notwithstanding, plastics have significant benefits for society, such as abundant sterile medical supplies; increased agricultural production; reduced food spoilage; reduced fuel consumption in lighter-weight vehicles; and, low-cost, net-shape manufacturing. Increases in oil prices that consumers are experiencing at the gas pump are also impacting the plastics industries where production costs are rising and being passed on to the consumer. While energy recovery through combustion, recycling, and minimizing plastics use can all aid pollution prevention, the new industrial biotechnology paradigm can be a more environmentally benign solution to the societal, economic, and environmental impacts of increasing oil consumption.

 Economically competitive properties are now well within reach among biomaterials including starch cellulosics, proteins, polylactides, soy and plant oil-based plastics, and polyhydroxyalkanoates. Several research priorities have been identified to improve production of biomaterials.

The primary need is the development of standards for assessing the energy content and emissions profiles for plastic materials. This is essential to ensure the pursuit of truly environmentally benign materials. Metabolic engineering routes to the synthesis of monomers and polymers should also be explored due to the increasing practicality of inducing the necessary genetic changes.

Advances in metabolic pathway modeling can further enhance these efforts by indicating promising targets for genetic engineering. Among these, modifications necessary to enable use of waste biomass feedstocks, such as lignocellulosics and waste oils, or to enable biosynthesis within crops that can be grown on marginally productive lands, such as switchgrass, would be especially valuable.

Biopolymers and other bioplastics could be more widely used in place of petroleumbased plastics if their physical properties (such as heat resistance and moisture permeability) could be improved. Conventional composites and nanocomposites in which the reinforcing agents are also based on renewable resources (biocomposites) are of particular interest in this context. In addition, biopolymers based on inexpensive monomers presently available using conventional fermentation technologies should be explored and developed where feasible.

B. BIOFUELS

Energy is a central issue in economic sustainability. Production and distribution of inexpensive energy in a variety of forms (electricity, heating and transportation fuels) is essential for maintaining industries and for supporting stable lifestyles for people. Transportation fuels dominate use of imported petroleum.

In the area of biofuels, fostering collaboration of scientists and engineers is critical. The absence of interdisciplinary collaboration is repeatedly cited as one of the greatest limits to the scale-up and commercialization of bioenergy technologies. Collaborations between those attempting to understand and engineer the organisms and those attempting to design optimal bioreactors and bioseparation processes should be encouraged and when appropriate, should include researchers from industrial laboratories. Such teams are essential to commercialization of the advances made in academic and governmental laboratories.

Within the field of bioethanol production, the most important challenge is the development of feedstocks based on waste biomass. Research in this area will end or reduce reliance on crops produced with conventional energy-intensive practices that makes bioethanol no more sustainable than fossil fuels. Obstacles to waste-based bioethanol include the absence of high-performance, low-cost cellulase enzymes and/or cellulolytic organisms; the separation of lignin from cellulose; the optimization of simultaneous fermentation of hexoses and pentoses; and the purification of the ethanol and recovery of other valuable byproducts.

Biodiesel development is also dependent on non-sustainable agriculture. Therefore, sustainable production of oilseed crops and the development of technologies to allow use of waste oils are important priorities. Following these, bioengineering advances are needed to be efficient in transesterification and separations.

Relative to other biofuels, biohydrogen is still in its infancy. Biohydrogen technology is actually five distinct technologies (direct photolysis, indirect photolysis, photofermentation, water-gas shift production, and dark fermentation) involving four very different types of microorganisms (green algae, cyanobacteria, purple non-sulfur bacteria, and anaerobic heterotrophic bacteria, respectively). While each type of technology faces its own particular challenges, a few priorities are common to all.

Of utmost importance to the three photolytic technologies is the reduction of photosynthetic antenna pigments. Second, the addition of heterologous pigments to allow utilization of photons outside the photosynthetic spectrum is also desirable. Vital to the two nonphotolytic technologies is the development of sustainable organic carbon sources. Current efforts underway to use various waste sources as substrates should be strongly encouraged to continue.

Within the realm of biorefinery platform technologies, the development of integrated bioreactor-bioseparation unit operations should be supported, especially those that can overcome inherent limitations of bioprocessing and other integrated designs that selectively remove the components limiting organism growth. Integration offers tremendous benefit for relatively little investment. Bioreactor design and operation can be further optimized with the assistance of improved theoretical models for reaction kinetics, including structured models. This would provide commercial viability for commodity products with narrow profit margins and for membrane-based separation technologies.

In addition, new benign solvent extraction processes are needed for bioseparations to avoid fossil-based and/or toxic solvents-supercritical CO2 is an excellent example. The development of new strategies to suppress or control membrane fouling in relevant separations would also be immensely useful.

C. RESEARCH STRATEGIES

Fostering interdisciplinary research can be accomplished easily by encouraging multidisciplinary teams through the research grant award process. Also, certain elements of the needed bioengineering platform technologies are already well supported by the USDA and to a lesser extent by the DOE. A joint program between the USDA/DOE that supports the development of bioengineering for energy production is in place. Additional partnerships with these agencies would help to improve the knowledge base of bioengineering for pollution prevention.

A. CURRENT STATUS OF ENERGY AND MATERIALS FEEDSTOCKS

1. The Petroleum Resource shortages are a natural consequence of the utility of the resource combined with human ingenuity. As a new resource is discovered, people invent uses for it in proportion to its adaptability; increased uses typically increase the demand for it often resulting in increased production, which thereby increases the opportunity for new uses to be discovered, and so on. In the case of petroleum, this cycle has progressed to such an extent that developed world economies are dependent on it for heat, food (through agriculture), shelter (through synthesis of construction materials), and transportation.

In the United States, for example, petroleum use has increased steadily from approximately 9.8 million barrels per day in 1960 to ~21 million barrels per day in 2005

  The present rate of demand increase is ~1.5 percent per year resulting in U.S. demand expected to increase 37 percent over 2004 levels by 2025

 Within this demand, transportation and industry, the latter including plastics and materials production, consume the greatest shares at ~66 percent and ~25 percent, respectively. Comparable increases have been observed in other developed countries as well If petroleum were plentiful, widely distributed, and environmentally benign, this situation would be no cause for concern. Unfortunately, though, it is not the case.

First, the demand of the developed economies for petroleum is now reaching a level that is comparable to known reserve limits. For example, an estimated 875 billion barrels of oil have been consumed since the dawn of the oil age while 1.7 trillion barrels remain in proven reserves (within oil fields discovered but not yet pumped out), and another estimated 900 billion remain to be discovered

 Of the 875 billion consumed, however, greater than 60 percent (550 billion) have been consumed since 1975. With world demand continuing to rise at ~2 percent per year, the world production peak is estimated to occur between 2026 and 2047

 Within the United States, crude oil production is expected to peak in 2010 ,and the remainder of the petroleum that is easily accessible given both geological and political constraints is expected to peak in that approximate time frame as well.

  This raises the second issue, that of petroleum accessibility, given both geological and political constraints. Geological factors dictate that not all petroleum is equally accessible. Fields that may lie in temperate zones within several hundred feet of the surface have understandably been the first to be exploited. This leaves oil beneath oceans, in remote Arctic regions, tightly associated with sands, and/or laden with impurities as an increasing component of that that remains to be exploited. Technological advances have greatly increased the amount of petroleum that can be extracted from the earth, once discovered, but often at high operational and environmental cost.

  Political factors also contribute to petroleum accessibility. While the United States was once the world’s greatest petroleum producer, it and many other developed countries are now net importers: the United States now imports approximately 56 percent of its demand, or ~11.2 million barrels per day .

  The United States is not only the greatest consumer of world petroleum resources–demanding ~25 percent of the global total production,but notable to foreign suppliers, the United States is also the greatest importer, with nearly double the net imports of second-ranked Japan. Of the 1.7 trillion barrels of oil in the world’s proven reserves, over half of those are located in the Middle East. Petroleum suppliers are therefore becoming increasingly concentrated in regions of the world, particularly the Middle East, that have historically been politically unstable and/or unfriendly to western interests.

  Finally, petroleum is far from environmentally benign. Petroleum combustion releases carbonaceous gases, principally carbon dioxide (CO2), carbon monoxide (CO), and methane (CH4), as well as sulfurous gases such as sulfur dioxide (SO2). Decades of climate and atmospheric composition data are now confirming the link between increasing concentrations of greenhouse gases such as those emitted by combustion of fossil fuels and increasing global temperatures.
 
In addition, concerns are growing about the volume of discarded wastes that the United States and other countries produce. Global consumption of petroleum-based thermoplastics, the greatest component, now exceeds 100 million tons per year, of which approximately half is discarded within two years of production. Much of the other half, used to generate products with longer lifetimes, is just beginning to enter the waste stream, with the result that plastic waste generation is expected soon to exceed the growth in consumption.

This, in turn, is expected to create a considerable demand on landfill space. An accompanying problem is that wealthy countries can export such wastes to poorer countries.

Although these practices have been addressed through measures such as the Basel Ban, diminishing waste volumes is the most straightforward solution to exploitation of vulnerable peoples and natural areas. As a result, the impetus for transition from fossil fuels to renewable energy sources and materials feedstocks is resulting as much from environmental considerations as it is from concerns about future conflict over petroleum resources.

 2. Benefits of Petroleum Replacement

Numerous technologies are under development for the replacement of petroleum as the primary energy source and materials feedstock in developed countries. Wind, solar, hydroelectric, geothermal, and biomass-derived power will each be called upon to contribute to the post-petroleum economy, and conservation measures are also expected to receive greatly increased attention. Materials derived from biological molecules are also gaining diversity and availability.

To what extent can petroleum be replaced, and by what alternatives, within the next decades? While this potential is debatable, a realistic best-case scenario can be presented given recent projections. In April, 2005, a report by the U.S. Department of Energy (DOE) and the U.S. Department of Agriculture (USDA) estimated that the United States could quite feasibly produce 1 billion dry tons of biomass feedstock (over half of which is waste) per year, enough to displace 30 percent or more of the present U.S. petroleum consumption for fuels and materials by 2030.

When this is combined with projections of solar and wind energy together providing 20 percent of the power demand in the industrialized world by that time, it appears that biological resources could become important contributors to the evolution of a post-petroleum world. Under these projections, CO2 emissions could peak before 2050 and conventional fossil fuel use could be virtually eliminated by 2100.

3. Unique Contributions from Biotechnology

  The application of biotechnology to the production of commodities–notably fuels, chemicals, and structural materials–increases the array of options available to supply sustainable resources and preserve the environment. In particular, through the use of biological feedstocks, biotechnology has the potential to minimize greatly the overwhelming dependence developed countries, particularly the United States, have on petroleum and other non-renewable fossil fuels for production of fuels and plastics. Numerous mechanical, geothermal, and electrical technologies offer valuable contributions to issues of energy independence and pollution prevention. At the same time, several unique advantages are brought by biofuels and bioproducts that will be highlighted in this report.

 First, many biotechnologies use the abundant, renewable, and potentially sustainablyproduced resource of plant biomass as the primary feedstock for liquid biofuels, biochemicals, and biomaterials. Cellulosic and other biomass is currently available at the commodity scale and is increasingly cost-competitive with petroleum, especially when environmental costs are included, on both energy and mass bases. Indeed, the land resources of the United States are capable of producing a sustainable supply of biomass sufficient to displace 30 percent or more of the country’s present petroleum consumption, amounting to approximately 1 billion dry tons of biomass feedstock per year.

  Second, microbiotechnologies have the potential to use simple, organic, and inorganic feedstocks in microbe-based bioreactors that generate desired products directly, without plant biomass intermediates. For example, photosynthetic microbial biohydrogen production requires only sunlight, CO2, salts, and water, and bioplastic precursors such as polylactic acid and polyhydroxybutyrate can be made directly by microbes as well.

  Third, biotechnologies make use of enzymes, proteinaceous catalysts that are often exquisitely selective and provide high rates of product generation. Unlike other catalysts, enzymes can be manipulated genetically to improve parameters such as substrate affinity, specificity, and catalytic rate, as well as tolerance to process conditions, longevity, and even production rate of the enzyme itself by the host cell.

  Finally, as a result of the above, many biotechnologies are able to avoid use of toxic feedstocks and processing reagents that are necessitated by conventional methods and thereby minimize toxic wastes. For example, biosynthesis of the denim dye, indigo, requires only glucose as substrate, in contrast to the conventional synthesis that requires benzene or other aromatic solvents

Bioengineering for pollution prevention is an emerging area of both an intellectual endeavor and an industrial practice. The economic driving forces, the importance of feedstock, and the scale of production all distinguish this arena of biotechnology from the pharmaceutical and nutritional sectors. While fossil fuel-based economies typically evolve from a relatively low-value commodity (e.g., kerosene for lighting) to intermediate-value materials (gasoline, plastics) and ultimately to valuable specialty chemicals (cosmetics, pharmaceuticals), it appears that the biobased economy is progressing from high-value products (pharmaceuticals) to those of intermediate value (industrial catalysts, plastics). As biotechnology evolves and matures, the production of large-scale, relatively low-value products such as fuels is becoming increasingly attractive and economically feasible.

B. CURRENT CHALLENGES

1. Cellulose Stability

The greatest impediment to widespread application of bioengineering for production of