SEatWtC Part 14: Energy Types and Sources

Future Energy Sources
Image © 2007 by Aleksandar Rodic

Energy Types and Sources

All global sources of energy except two can be derived from a single energy supply: the sun. The only two energy supplies that don’t receive their energy content from the sun, either directly or indirectly, are geothermal and nuclear energy. Solar power is the only energy supply that receives its energy content directly from the sun, but all others receive their energy from the sun indirectly. Crude oil is simply plant and animal matter that has decayed, compressed and stored for a very long time. Since plants get their energy from the sun, and since animals get their energy from plants and other animals, the initial source of energy in crude oil is the sun. The same argument is made for Natural Gas or any other organic combustion fuel. Even hydrogen, which is not organic, has to be created from either organic fuels or from water. Even wind and hydropower ultimately get their energy from the sun. Wind gets its energy from pressure gradients in the atmosphere caused by heating and cooling cycles that are caused by: the sun. Hydropower produces energy by capturing the potential energy of water at one elevation as it moves to a lower elevation. How does the water get from lower elevations to upper elevations? The sun evaporates it so that it may fall as rain in the water cycle.

Geothermal energy captures heat from the Earth’s core and nuclear energy captures heat from the radioactive decay of certain elements. Even these two energy sources can indirectly attribute their energy to the sun, because millions or billions of years ago the sun provided a gravitational center around which matter collided, producing the Earth itself and the heavier radioactive compounds found therein.

The point of this is that no matter what we do to conserve or use energy wisely, there will come a time when the sun stops shining and our source of energy will cease. Hopefully by that time we’ll be able to pack up and move to another solar system, but it is important to keep this in perspective. Knowing that the sun is the ultimate source of all our energy is also important because it shows us where we should turn for our energy demands in the future. More on that later. First, let’s discuss our current energy sources more and see how they might affect the near future of business and politics.

Tune in tomorrow for Part 15 of SEatWtC!