The population of the United States is now greater than three hundred million, and that number is certainly not going to decrease any time soon. As the country continues to grow, the energy needs of those people are going to expand as well. With the ever-increasing number of electronic devices and appliances, the power requirements of most individuals will continue to grow.
The bulk of American electricity is generated by the burning of fossil fuels (coal and oil) and an increasing amount is provided by alternative forms of energy (wind and solar). In order to use the fuel, of course, it has to be recovered from the earth. Here's how energy companies and scientists know where to find the raw materials we need to power our future.
Coal is found in places that were once prehistoric ocean floors or swamps; anywhere plants and animals were buried quickly under successive layers of silt. The land under the United States holds enough coal to meet our needs for centuries to come. In fact, coal is so common and easy to find that exploration is not difficult.
Geologists are able to locate coal seams in a few ways. Sometimes, coal seams extend right to the surface. Coal is also sometimes found because of a kind of rock called "clinker." These hydrocarbon-infused rocks form when coal on the earth's surface is ignited by fires. If a geologist sees clinker, then he or she knows that there is a deposit of coal in the ground.
Petroleum is liquid fossil fuel held between layers of impermeable rock. As a result of this, it is often under great pressure. Oil can sometimes be easy to find. Sometimes, it even bubbles up to the surface, in the same way the La Brea Tar Pits were formed. Petroleum is usually trapped under a layer of natural gas. Once in a while, that gas springs through the surface. If this happens in the wrong place, bad things can happen. Grazing animals have been smothered when the burst of gas was fast and great enough to sneak up on the creatures. (Natural gas has no odor, so it can be difficult to even know that kind of eruption is happening.) Still worse, the gas can be ignited by sparks or fire, causing a sizable explosion. These events, however, are valuable clues as to where petroleum can be found.
Seismic analysis is a popular way to find oil deposits. Rock is solid, of course, and oil is liquid, which means that waves travel through them at different speeds and magnitudes. If they think they are in a promising location, geologists will set off an explosion, which sends rumblings through the ground. Through the use of seismographs left in different places, scientists can get a picture of the layers underneath the ground and what is contained in them. By comparing the strength of the shocks, the likely location of oil can be triangulated. Unfortunately, no method is foolproof, and the only way to be sure is to drill and see what you find.
Alternative and Renewable Energies
Thanks to the evolution of technology, new ways of generating electricity are becoming feasible. Figuring out the best locations for wind farms and solar energy collectors are completely different concerns than those involved in finding fossil fuels.
Obviously, wind farms must be placed in locations that experience strong and constant wind. Transporting the electricity generated by the turbines is a big concern, so wind farms must be located as close as possible to existing power facilities. This helps keep costs down, reducing the need for cable and transformer stations. Many people feel that turbines are an eyesore, so they must be placed on land that is remote enough to reduce this concern.
Solar power collectors have many of the same concerns as those related to the placement of wind farms. These fields of solar cells must be very large, especially if they are intended to serve large populations. Ideally, there must be room for the facilities to grow. Just as is the case with wind power, the weather must be favorable, with clouds at a minimum.
Both solar and wind power face the threat of global warming. Many scientists believe established weather patterns will change, which means that power plants located in the right place today may not be in the optimal place in the decades to come. These and other challenges will be addressed, and scientists will devise new ways to find the raw materials and conditions that will allow power companies to fulfill our growing needs.