Doomsday scenarios — "What will we do when we run out of oil?" — are nothing new. For decades, analysts and industry experts have been trying to predict when the oil supply will be critically low or depleted altogether, and what the results might be. The United States is investing in energy technology with the hope that we can reduce the country's dependence on petroleum-based fuels, and thus, the amount of oil we import. But is that even possible? Let's consider the factors involved in this delicate, evolving equation.

The United States is the third largest oil producer in the world (behind Russia and Saudi Arabia), with an output of about 8 to 9 million barrels a day. The U.S. was able to supply 90 percent of its own oil demand until the 1970s; however, we currently use about 20 million barrels of oil a day. Because we use about twice as much as we make, the additional oil has to come from somewhere else. We import about 50 to 60 percent of our oil from other countries, mostly Canada, Mexico, Saudi Arabia, Venezuela and Nigeria.

This arrangement presents several problems. Oil is expensive, and there is a finite supply of crude oil so once all the oil on the planet has been found and processed, no more can be produced. Because of these factors, oil remains a source of much of the world's political tension, especially since a large amount of it is found in Africa and the Middle East, and supply can be threatened during times of war. And as worldwide supply dwindles, many oil-producing countries may want to keep oil for their own needs, which could lead to further hostile conditions or political unrest. So, reducing our oil imports will improve our national security by making us less vulnerable to global conflict.

Reducing our dependence on foreign oil also helps the U.S. economy by removing some of the volatility of global oil prices. When oil is trading at a steep price (or even when prices are simply expected to rise), the price of gasoline immediately skyrockets. When it costs more to fill up a car, consumers spend less money overall, and the economy suffers. However in this case, consumers aren't spending less money and saving more; they're simply being forced to reallocate their funds.

The good news is technology in the energy industry is constantly improving. New oil deposits are still being discovered, with some experts estimating there are about 1.7 trillion barrels of reasonably accessible oil in the ground worldwide. And deposits of oil that were previously deemed inaccessible or economically unfeasible to drill, are now more easily developed, even deposits in the U.S., which has seen production increase 10 percent since 2008. But the truth remains that oil is a finite resource, and supply depends on a lot of factors that can't be controlled or predicted.

Increasing domestic production is helpful, but it isn't the whole solution. To cut our dependence on foreign oil, we have to cut our dependence on oil. So even as oil production continues, other new technological developments, such as more efficient vehicles, will continue to reduce the United States' reliance on petroleum-based fuels. Experts believe that we will achieve a reduction in dependency, but the process will be gradual. The U.S. Department of Energy and the Energy Information Administration predict that we are on track to reduce our dependence on foreign oil, as a result of a shift to other energy sources, such as biofuels. By 2035, the U.S. is expected to reduce oil importation to about 45 percent.