Fossil fuels, or conventional fuels, have a big shortfall – resources are limited. These conventional fuels have been formed by the anaerobic decomposition of the remains of organisms including phytoplankton and zooplankton, and this process takes millions of years. In the first stage the materials converted into kerogen, which can be found in oil shales. Subsequently the process produced liquid and gaseous hydrocarbons. This process is called catagenesis, where organic kerogens are broken down into hydrocarbons.
Due to this process, a wide range of organic, or hydrocarbon, compounds can be found in any given fuel mixture. The specific mixture of hydrocarbons gives each fuel its characteristic properties, such as boiling points, melting points, density, viscosity et cetera. For instance, fuels like natural gas, contain only very low boiling components. On the other hand, gasoline or diesel contain much higher boiling components.
Natural gas was once seen as an un-needed byproduct of petroleum production. However, nowadays natural gas is considered a valuable resource. Heavy crude oil is an important source of fossil fuels, which is much more viscous than conventional crude oil and for instance tar sands, where bitumen are found mixed with sand and clay. Oil shale and similar materials are sedimentary rocks, containing kerogen. This is a complex mixture of high-molecular weight organic compounds, which yield synthetic crude oil when heated.
As stated before, resources of these conventional fuels are limited. Also the pollution side-effect of extraction is a big drawback, of which the latest BP-oil rig disaster in the Gulf of Mexico a dramatic example. Research into alternative energy has been intensified over the last years, ranging from solar energy, and energy produced by wind and water.
First generation Biofuels
First generation Biofuels (1G) are derived from sugar, vegetable oil or animal fats using conventional technology. Ethanol fuel is the most common Biofuel worldwide, and the most important in Bazil. Through a complex process using wheat, corn, sugar beets and sugar cane, Biofuel can be derived. The problem with this first generation Biofuel is that it competes with food (growing capacity) and forested areas. So farmers who grow soy, wheat or corn for producing Biofuels, cannot use the land for growing food crops.
Second generation Biofuels
Second generation (2G) Biofuels try to avoid the need to use cultivated areas. The goal of the second generation is to extend the amount of Biofuels which can be produced sustainably. This can be achieved by using biomass consisting of the residual non-food parts of current crops. Second generation Biofuels use biomass to liquid technology including cellulosic Biofuels. 2G Biofuels do have the same limitations as 1G Biofuels: it still needs crops (or crop waste). Producing 1G and 2G Biofuels releases carbon dioxide, which is also a big negative factor.
Third generation Biofuels
One interesting third generation Biofuel is produced from algae (or algaeoleum). The advantage is that algae can produce up to 300 times more oil per acre than conventional crops, like grape seeds, palms, soybeans. Algae have a harvesting cycle of only one to ten days and it is possible to harvest in a very short time frame. Algae are able to grow 20 to 30 times faster than food crops and can also be grown on land which is not suitable for other established crops. This reduces the problem of taking away pieces of land from the cultivation of food crops. Another big advantage is that production of Biofuel from algae is climate (or CO2) neutral. A big disadvantage is the cost: food grade algae costs approximately $5,000 per tonne.
Another interesting 3G Biofuel is that derived from bacteria. The deadly E. coli bacteria might seem like an unlikely ally, but scientists California claim they have successfully genetically manipulated a deadly bug and a host of other bacteria to produce pure hydrocarbon chains that can be processed into Biofuels. In fact, they’re performing so well that they can coax the bacteria into producing a substance that’s exceptionally close to crude oil – minus the sulfur impurities that taint the oil we pump out of the ground.
An interesting question could be: are “bug farmers” the next great oil barons? Companies active in Biofuel derived from bacteria are for instance LS9, Aurora Agae, Algenol Biofuels, Amyris Biotechnologies, Bio Architecture Lab, Sapphire Energy, Synthetic Genomics, Targeted Growth and Joule Unlimited. This list of companies is not extensive!
In September, the American company Joule Unlimited was granted a US patent for an engineered bacterium (cyanobacteria) which produces liquid hydrocarbon fuels from sunlight and carbon dioxide. Joule Unlimited claims boldly that it can produce diesel fuel directly by only using sunlight and waste carbon dioxide in glass bioreactors for as little as $30 a barrel. To put in perspective: WTI Light Sweet Crude costs about $82.50 per barrel.
Although this might be a breakthrough the process of producing Biofuel from bacteria takes a lot of time and effort. Oil has to be extracted from algae and subsequently the output has to be refined into useful Biofuel. In other words, before Biofuel from algae could be commercialized, it might take ten years.
Whether or not it might take a lot of time before conventional oil could be replaced, it might be worthwhile, or even necessary, to keep track of this interesting 3G Biofuel development.