Carbon emissions taxes and rising fossil fuel prices have accelerated the introduction of alternative aviation fuels which could end up widely used in passenger jets within the next 4 years. Some airlines are starting sooner.

Deutsche Lufthansa will begin using alternative fuel for regularly scheduled flights within Germany beginning July 2011. The airline will operate an Airbus A321 with a mix of biofuel and conventional jet fuel on its route between Hamburg and Frankfurt. Only one engine will operate with a mix of alternative and traditional fuel, while the other engine will be powered exclusively by conventional jet fuel.

After years of testing, airlines and aircraft manufacturers are taking a cautious approach to the use of biofuels. Engines will still need to be tested and observed for any effects that the new fuels will have on efficiency, durability and maintenance.

Environmental concerns are definitely driving the move toward alternative fuels but economic factors also play a part. Carbon emissions taxes are emerging in several aviation markets. For the airlines they create upward financial pressures beyond rising jet fuel costs. This could lead to higher fares. Airlines will have to comply with emissions standards or face penalties in a growing number of markets. The use of biofuels is one way to cut down on greenhouse emissions and airlines are increasingly eager to make the move.

Australia is eyeing the use of biofuels derived from camelina plants and will open its first refining facility in 2015 when it expects wider use of the alternative fuel. A group that includes Qantas, Virgin, Boeing and Air New Zealand has committed to a plan that seeks a 5 percent biofuel component in Australia's aviation fuel supply by 2020. By 2050 this commitment increases to 40 percent, according to The Sydney Morning Herald.

Obstacles to the widespread use of biofuels remain, however. The land used to farm the plants of choice will need to coexist with that used for food farming. Proponents of the use of biofuels insist that world food supplies not be compromised by the production of biofuels. Testing of alternative fuels at high altitudes and extreme conditions will continue and standards for the quality of the fuels will likely be a global initiative undertaken by industry bodies. The economic viability of alternative fuels also depends on the cost of fossil fuels and the growing practice of taxing carbon-producing activities. These dual threats, which could likely result in higher fares for passengers, will probably put biofuels on an accelerated path to acceptance and utilization.