The internal combustion engine is well-established around the world as crucial for transportation, and those engines require fuel. it is pointless to deny that fact. although conservation always can and should play an important role in reducing the use of transportation fuels, that use cannot go to zero. therefore, a steady supply of fuel for engines that power cars, trucks, farm equipment, and airplanes is essential to be able to succeed in the global economy and to maintain an acceptable standard of living.
Approximately 60% of the world’s known oil reserves are in the Middle East, and almost every industrialized country imports at least some oil from that region of the world. further, since oil is a highly fungible commodity, the decisions on the volume of production of oil by the oil cartel have a major impact on its price. by adjusting production appropriately, Middle Eastern oil producers can exert a lot of control over the supply of oil, and therefore its price. it follows, then, that energy independence is possible only if we either increase the supply of our own oil or find alternative means of producing a suitable substitute.
Enter biofuels. Defined as any fuel-solid, liquid, or gas-derived from recently dead biological material (as opposed to biological material that has been dead for millions of years), biofuels offer a path to increased energy dependence. Biofuels are renewable, sustainable, and domestically-produced. indeed, since it is from agricultural feedstocks that biofuels are overwhelmingly derived, one can think of biofuels as a type of solar energy. Through photosynthesis, plants use energy from the sun to grow and accumulate fermentable sugar raw materials and oils.
Using plant sources we can produce two biofuels now in large enough quantities to have an impact on the market for transportation fuels: bio-ethanol and biodiesel. although ethanol is only about 60% as good a fuel as gasoline based on energy content, and has other draw backs including its inability to be transported through the existing pipeline infrastructure, it can be blended into gasoline up to about 15% without requiring any modifications to most existing car and truck engines.
Biodiesel is entirely another story. Produced from plant or animal fats, biodiesel can be blended in substantial amounts with traditional petroleum-derived diesel or in some cases used directly as a transportation fuel. Unlike ethanol, biodiesel is a good fuel, and it has the added advantage that it is cleaner-burning than diesel. Its problem is that there is nowhere near enough plant-sourced oil to produce more than a 5-10 percent of our diesel needs.
Since ethanol can be produced now in vastly larger quantities using existing technology than can biodiesel, it is the only biofuel currently available that can meaningfully reduce our demand for foreign oil. although ethanol is certainly not the most desirable biofuel, there is simply no other option currently.
That must change if biofuels are to realize their potential as a replacement for petroleum-derived gasoline in transportation fuels. There are three important developments to look for in the near future in the USA. The first is the switch from corn to cellulosic waste as the source of fermentable sugars for biofuel production. Cellulosic pilot plants have already been built and processes are being tested, so this switch will likely begin to happen at the commercial level over the next 2-5 years. Once this shift is complete, the diversion of land and agricultural products from food uses to biofuel production will be essentially eliminated, and the upward pressure on food prices will abate. The second important technological shift will be toward the production of better biofuels such as butanol and hydrocarbons and away from ethanol.
Both butanol and hydrocarbons such as terpenes are much more gasoline-like, have higher energy content, and posses none of the drawbacks of ethanol as a transportation fuel. we already see a heavy investment in research and development in these areas. Once the technology is well-enough developed to be commercially viable, cellulosic-derived, more practical biofuels will enter the marketplace that are ideal replacements for oil-derived fuels. The third breakthrough will be the use of algae as a source of oil for biodiesel production. Technological improvements in the efficiency of growing algae and recovering the oil are needed for algal biodiesel to be economic, but steady progress toward those goals is being made. Once these three developments are in place, we will have taken decisive steps toward energy independence and relief of cartel-imposed price controls.