lunes, 21 de mayo de 2007

Green science: Biofuels and the Future of the environment

The rising prices of petroleum fuel have pushed alternative fuels such as biodiesel and bioethanol into the spotlight. Despite their rising popularity, many seem to misunderstood what biofuel is.

Unlike traditional fossil-based fuels such as diesel and gasoline, biofuels are environmentally friendly, renewable fuel. As the name implies, biofuels are extracted from plants -- biodiesel is typically made from new or used vegetable oils and animal fats, while ethanol is made from any plant life rich in sugar, like corn and sugar cane.

Currently available biofuel offerings on the market use a blend of biodiesel or ethanol with traditional petroleum fuel. For example, biodiesel is typically made up of 20 percent biofuel and 80 percent petroleum, called B20 fuel. Bioethanol blends are made with 5 to 10 percent ethanol.

For its Bio Pertamax, Pertamina uses 5 percent of ethanol. In this sense, biofuels can be regarded as additives rather than replacements for fossil-based fuels such as petroleum.

However, much higher blends of biofuel exist that can be considered "real" alternatives for petroleum.

Neat biodiesel, or B100, is made entirely from biodiesel, while ethanol-based biofuels such as E85 and E95 use 85 percent and 95 percent ethanol, respectively.

Such high-level blends will certainly reduce significantly the world's dependence on fossil-based fuels; however, they are not without drawbacks.

Ethanol is much more corrosive and burns at lower combustion temperatures than traditional gasoline. The corrosive nature of ethanol and biodiesel means cars -- or engines in general -- must use additional protection to prevent damage to fuel-related systems if they use high biofuel blends.

With lower blends (10 percent for ethanol and 20 percent for biodiesel), engines and fuel systems do not need the additional protection. Due to its lower combustion temperature, gasoline engines still need a 15 percent blend of gasoline; otherwise, the engines will fail on a cold start.

However, diesel engines are much better suited for low-burn temperature fuel, making E95 a better choice for diesel engines.

It is also true that biofuel generally produces less energy than petroleum, meaning slightly lower mileage for users. This is because traditional gasoline and diesel engines are built without biofuels in mind.

Biodiesels have more oxygen content than traditional diesel, while ethanol-based biofuels have more octane but a lower combustion temperature. Biofuel-aware engines such as flexible fuel vehicle (FFV) engines in newer cars should have no problems with E85 for gasoline engines or in the case of biodiesel, neat biodiesel for diesel engines.

These two characteristics of biofuels actually have a positive effect -- a more efficient combustion, which means less pollution. So the use of biofuels should help the current energy crisis and even protect the environment.

Various studies show that neat biodiesel reduces carbon dioxide emissions by more than 75 percent compared to petroleum diesel. Using B20 biodiesel reduces carbon dioxide emissions by 15 percent.

Tests at the National Center for Vehicle Emissions Control and Safety at Colorado State University document a 25 to 30 percent reduction in carbon monoxide emissions when automobiles burn a 10 percent blend of ethanol.

Let's not forget the economic impact on farms and the national workforce.

The different characteristics of biofuels do present new challenges for distribution and storage.

Such facilities must be vigilant about water produced either from condensation due to cold weather or seepage. Rust, microbes and other deposits sticking to the insides of a fuel tank or container detach more easily with biofuel.

A high enough buildup will lead to blockage in fuel systems and failed starts in engines. Of course, this doesn't just affect cars and engines -- it also means fuel pumps and gas stations must invest in new pumps, storage tanks and other equipment.

In fact, Indonesia's entire fuel distribution pipeline will likely require an upgrade to be biofuel-ready.

Biofuel certainly has the potential to replace traditional petroleum -- a clean, renewable energy upon which we can all depend.

At this time, biofuel contribution to the country's energy consumption is still very small.

For biofuel to gain widespread use, the necessary infrastructure -- more FFVs on the market, upgraded biofuel-ready supply and distribution channels, including a quality standard on biofuels -- must be in place.

A paper written by Soni Solistia Wirawan and Armansyah H. Tambunan of the Agency for the Assessment and Application of Technology (BPPT) titled The Current Status and Prospects of Biodiesel Development also cites other necessary steps. These concern "how to accelerate the construction of new biodiesel plants, plantations as a key driver in the continuity of raw material, which is supported by committed government policy and regulation. This implies all biodiesel stakeholders should work harder for the success of the biodiesel program in Indonesia".

Such a project will likely be costly, but the rewards would be well worth the effort. Biofuels are not just a solution to our energy problem, but also a long-term environmental solution.

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