Over the years, the prices of gas and diesel changed drastically. Only a few short years ago gas prices were around a dollar or a dollar fifty. Now gas prices have jumped to the four dollar range. Diesel has seen even more drastic changes. It's price has increased to a point of nearly a dollar higher per gallon than standard unleaded gasoline.

Part of these changes are demand related. As more people drive, the price of fuel is bound to increase. At the same time, we have limited supplies of fossil fuels. That drives up prices as well.

Other events of the last few years have increased the cost of fuel in America. Primarily the war on terror being the main culprit. Running the world's largest military in two active wars is costing the country billions of dollars each month. Much of that cost is fuel costs. Many of the tanks, trucks, and SUV's run on diesel fuel. That extra demand for fuel cannot be underestimated.

While we are fighting in Iraq and Afghanistan, we are getting the majority of our fuel from the Middle East. A large portion of the cost of gas is just in shipping the oil from the Middle East, to the United States. If we could get the oil from a closer source, the shipping costs would not be so high.

Traditionally, diesel fuel has been cheaper than gasoline, but now that commercial and government demands for the fuel are so high, the price has skyrocketed to unbelievable levels. At one time diesel was much cheaper than gasoline. Now, to help keep gas prices lower, it appears that the oil companies are pushing diesel prices since the government and shipping companies have no choice but to pay, otherwise their operations cease to function.

When it comes to a choice between gasoline and diesel fuels, the price and fuel economy at one point made diesel a clear winner. Now, it appears that diesel prices have spiraled out of control to the point that diesel has for the most part lost its economic advantage over gasoline.

At this point the only way that diesel can become a viable alternative to gasoline is if soy and algae based biodisel become viable fuel sources. Creating a food based fuel such as soy biodiesel has proven to be an unwise decision economically speaking thus far, but it is possible that if algae biodiesel production can scale that it could become a viable alternative to traditional petrol based diesel.