Treethanol is an ethanol fuel (more precisely cellulosic ethanol) made from trees.
Summary
The biofuel is a contender in the race to find an energy alternative to fossil fuels. Proponents of Treethanol claim that its energy yield is higher compared to the energy required for production when compared with more common sources of ethanol i.e. sugar cane and corn.
Production
Cellulosic ethanol is produced using the lignocellulose biomass that comprises much of the mass of plants. Essentially at the core of the plant material is cellulose, which can be broken down into simple carbohydrate sugars. After these sugars have been extracted, they can be then be fermented into an alcohol, which is known as ethanol. The most widely used and promising means of creating cellulosic ethanol is called the cellulolysis process. The process consists of hydrolysis on pretreated lignocellulosic materials. Then enzymes are used to break down cellulose into glucose. This glucose is then fermented and distilled. The pretreatment step mentioned above is necessary when processing cellulosic ethanol because the glucose (sugars) are not readily accessible as they are with other ethanol sources such as corn or sugar cane. Rather, the cellulose in wood must be separated from the encapsulating hemicellulose and lignin.
There are three types of pretreatment: physical, chemical, and biological. Physical treatment involves physically reducing wood particle size. This can be accomplished through chipping, grinding, etc. Biological treatments involve the use of microorganisms to break down the wood. This type is considered favorable to physical pretreatments because it consumes far less energy in comparison, but the biological method has not proven to be scalable to an industrial level. The chemical method utilizes an alkaline or otherwise acidic medium to make the cellulose within wood fibers more accessible. This has shown to be the most efficient and has the lowest energy cost.
Forest trees make up more than 90% of the total terrestrial biomass while performing functions such as carbon sequestration, producing oxygen, and promoting biodiversity. Trees are a promising source of ethanol because they grow all year round, require significantly less fertilizer and water and contain far more carbohydrates (the chemical precursors of ethanol) than food crops (like corn) do.
Sources
Poplar, Willow, and Eucalyptus tree are emerging as favorites in the process of creating Treethanol. This is due to their ability to grow at a fast rate in many parts of the world.
Applications
Treethanol is not an energy source that promises to power houses in the future, but rather it can be taken advantage of in applications where combustion engines are used. Approximately 85% of US energy consumption is produced from fossil fuels such as natural gas, coal, and oil. With China, India, and other rapidly developing nations increasing their demand for fossil fuels, the world’s total energy use is expected to grow by 57% over the next 20 years. It is estimated that the U.S. alone uses 140 billion gallons of fuel per year for transportation alone. Not only can Treethanol be mixed with ordinary fuels, it can also be burned directly in modified engines to greatly reduce greenhouse gas emissions.
Advantages
Cellulosic ethanol is an environmentally friendly and renewable transportation fuel that can be produced from forest biomass. Trees are a particularly promising feedstock because they grow all year round, require vastly less fertiliser and water and contain far more carbohydrates (the chemical precursors of ethanol) than food crops do. Also, compared to corn ethanol, cellulosic biofuel does not require the same quantity of fertilizers, pesticides, energy, or water to grow. The most important attribute of this type of ethanol is, like all types of ethanol, it is renewable. If you want or need to make more of it, you just grow more trees.
The development of all types of biofuel, including Treethanol can be of importance for countries looking to decrease their dependence on petroleum, especially those countries that import most of their petroleum and also have plenty of crop/forest land such as New Zealand and Sweden.