WHAT MAKES OIL EFFICIENT TO USE?

BY ISABELLE

Chemical properties
     Oil consists of compounds of only two elements, carbon and hydrogen. These elements form a large variety of complex molecular structures. However, regardless of physical or chemical variations, almost all crude oil ranges from 82 to 87 percent carbon by weight and 12 to 15 percent hydrogen. Bitumens are mixtures of hydrocarbons that are obtained as residues from the distillation of petroleum or coal, e.g. asphalt or petroleum. Bitumens generally vary from 80 to 85 percent carbon and from 8 to 11 percent hydrogen.

How oil generates power
     There are several ways technologies are used to convert oil into electricity. First is conventional steam - Oil is burned to heat water to create steam to generate electricity. Next, the combustion turbine - Oil is burned under pressure to produce hot exhaust gases which spin a turbine to generate electricity. Then there is the combined-cycle technology - Oil is first combusted in a combustion turbine, using the heated exhaust gases to generate electricity. After these exhaust gases are recovered, they heat water in a boiler, creating steam to drive a second turbine. Also, as used with cars, the oil is used for a chemical reaction in the engine that causes the pistons to move the crank shaft.

Are there alternatives to oil that are as efficient? 
          Well, there certainly are substitutes for oil, but it’s difficult to see any of them as superior—or even equivalent—from a practical, economic point of view. Just a few years ago, ethanol made from corn was hailed as the answer to our dependence on depleting, climate-changing petroleum. Government mandates to blend ethanol into gasoline further supported the industry’s development. But that experiment hasn’t turned out well. The corn ethanol industry went through a classic boom-and-bust cycle, and expanding production of the fuel hit barriers that were foreseeable from the very beginning. It takes an enormous land area to produce substantial amounts of ethanol, and this reduces the amount of cropland available for growing food. Indeed, they will not comprise much of an energy source at all in the true sense, but will merely serve as a means to transform energy that is already available into fuels that can be used in existing engines in order to accomplish selected essential goals. In other words, biofuels will substitute for oil on an emergency basis, but not in a systemic way.
     The issues arising with materials synthesis are very similar. In principle it is possible to synthesize oil from almost any organic material. We can make petroleum-like fuels from coal, natural gas, old tires, even garbage. However, doing so can be very costly, and the process can consume more energy than the resulting synthetic oil will deliver as a fuel, unless the material we start with is already very similar to oil.
     It’s not that substitution can never work. Recent years have seen the development of new catalysts in fuel cells to replace depleting, expensive platinum, and new ink-based materials for photovoltaic solar panels that use copper indium gallium diselenide (CIGS) and cadmium telluride to replace single-crystalline silicon. And of course renewable wind, solar, geothermal, and tidal energy sources are being developed and deployed as substitutes for coal.
     Electric cars have been around nearly as long as the automobile itself. Electricity could clearly serve as a substitute for petroleum—at least when it comes to ground transportation (aviation is another story—more on that in a moment). But the fact that electric vehicles have failed for so long to compete with gasoline- and diesel-powered vehicles suggests there may be problems.
     The view that bio fuels are unlikely to fully substitute for oil anytime soon is supported by a recent University of California (Davis) study that concludes, on the basis of market trends only, that “At the current pace of research and development, global oil will run out 90 years before replacement technologies are ready.”
     Theoretically, the substitution process can go on forever—as long as we have endless energy with which to obtain the minerals we need from ores of ever-declining quality. But to produce that energy we need more resources. Even if we are using only renewable energy, we need steel for wind turbines and coatings for photovoltaic panels. And to extract those resources we need still more energy, which requires more resources, which requires more energy. At every step down the ladder of resource quality, more energy is needed just to keep the resource extraction process going, and less energy is available to serve human needs
     It could be objected that we are thinking of substitutes too narrowly. Why insist on maintaining current engine technology and simply switching the fuel? Why not use a different drive train altogether?