By now, everyone likely knows the troubles with oil?it’s costly, the use of it pollutes the air and water, and obtaining it is often politically volatile. Even if all that could be brushed under the rug, one looming problem still exists. We’re running out.

It’s no secret the world petroleum reserves are shrinking. While it is difficult to find reliable data on just when the last drop will be pumped, a 2008 report from the International Energy Agency indicates that demand is quickly outpacing supply growth. They project demand will rise to one million barrels per day by 2013.

So what are the options?

The consensus in the car industry is leaning towards electric engines?gas-electric hybrids like the Toyota Prius and Chevy Volt in the short term, and fully-electric vehicles like Tesla Motor’s Tesla Roadster in the future.

While that may solve the issue of powering the world motor pool, it creates a monumental new burden on the power generating industry. According to the Energy Information Administration, nearly half the electricity in the United States is generated by burning coal, another finite resource that pollutes the atmosphere. New ways of generating electricity may be needed if we are to power both our infrastructure and our vehicles.

Converting to save green

With this in mind, some are looking at new fuels altogether, either in the form of plant-extract ethanol or biodiesel and recycled cooking oils.

Radio talk-show host Phil Valentine converted a diesel-fueled 1985 Mercedes-Benz?nicknamed “Bennie”?to run on biodiesel he produced from recycled cooking oil. He charted his process on the air and on his site, valentinebiofuels.com.

“This site is for people who want to get off the pipeline and stop sending billions of our dollars overseas to fund regimes that hate our guts . . . we’re all about finding ways to put more green in our pockets instead of our tanks so we can enjoy the American dream to the fullest. At this point, there is no silver bullet for our foreign energy dependence problems. This site is dedicated to finding viable solutions,” Valentine wrote.

Valentine used the Azure Biodiesel Fuelmeister II to produce his fuel, a system that costs roughly $3,000 to start, with any number of extras that can drive up the price. Similar systems vary in price based on how much fuel a person wants to produce, from $400 “starter kits” to massive $9,000 packages. Kits to convert car engines to biodiesel range from $1,300 to $3,500. In both cases, guides exist online to do the work without kits and at lower cost, but they often require more time and mechanical ability.

A similar conversion project at Middle Tennessee State University, the “BioBus,” converted a commercial, diesel bus to run on multiple fuels.

“The BioBus runs on petro-diesel, biodiesel, and used cooking oil, each in three separate tanks. Originally we wanted it to run only on used cooking oil collected from the cafeterias on campus to fuel it,” Russell Chair of Manufacturing with the Engineering Technology Department at MTSU Dr. Charles Perry said.

Initially converted to run on used cooking oil, compatibility for biodiesel was added later to allow for real-time highway emissions testing and the ability to switch between fuels during operation. Once issues with MTSU’s budget are worked out, Perry said he plans to find a better mechanism for obtaining oil and storing the vehicle.

While “Bennie” and the “BioBus” are examples of successful conversions, skepticism remains as to how viable biofuels are on a large scale.

Is ethanol sustainable?

Ethanol, a type of plant-derived alcohol, has been touted as a solution to fuel needs and is already being used to augment gasoline at pumps. However, ethanol is often produced from corn, and even if America’s entire acreage of corn was converted into ethanol, it could only fuel roughly 12 percent of the American motor pool, according to a report from the National Academy of Sciences.

Moreover, many feel the energy required to produce ethanol is greater than the energy received by burning it. One study published in the journal Critical Reviews in Plant Science warns that in the process of fertilizing, growing, harvesting, converting, and shipping, the energy required to produce ethanol fuel is six times greater than the energy it generates.

Still more research to be done.

Biodiesel, a derivative of natural oils often obtained from soybeans that is chemically similar to petro-diesel, is often mixed with standard diesel. Like ethanol, however, issues exist in producing adequate amounts to function on a large scale.

“Any of these biofuels, whether it’s ethanol or biodiesel, have problems. The energy of ethanol compared to gasoline isn’t nearly as high. Ethanol is water-soluble, so in your transportation infrastructure, you can’t allow it to be exposed to water because it will absorb it, and that’s basically all that gin is?ethanol and water,” Perry said.

Biofuel production still has several options. Perry mentioned the use of microbes and cellulose waste material as a means to producing ethanol, or the use of genetic modification to induce greater oil production from soybeans. However, in both scenarios, the technology has yet to catch up to the problem.

So, as we wait for the tap on the world oil reserves to run dry, what option should we be pursuing?

“We don’t know what will be the most fruitful fuel of the future. I think the jury is still out on which technology we’ll favor, but right now, it’s going to take time to find a solution, so we should be pursuing them all,” Perry said.