Abie L. Benítez
All forms of energy are stored in different ways and in a variety of energy sources some of which we use everyday. For the purpose of clarification these sources are classified in two different categories: renewable and non-renewable. I found that when we talk about renewable energy sources we mostly refer to a source that we can use over and over again without permanently depleting the planet’s supply of those sources. On the other hand, a non-renewable source of energy is that which we can use but we cannot recreate in a short period of time.
Renewable Energy
Renewable energy sources include solar energy, wind, geothermal, biomass and hydropower. Solar energy comes from the sun and can be turned into electricity and heat. To convert sunlight into electricity requires a solar cell such as the ones you can see in calculators which are also called photovoltaic cells or modules. Through a group of cells electrically connected in one frame they convert sunlight (photo = light) directly into electricity (voltaic=electricity).
The wind power has been used for hundreds of years. Who has not heard of or seen the wind powered grain mills of Holland? It seems that other pre-industrial societies utilized the wind too. But, what about today: How do we use wind power? We utilize wind to convert it into electrical power through horizontal axis wind turbines. These turbines consist of three parts: the tower, the blades, and a box behind the blades, called the nacelle. Inside the nacelle is where motion is turned into electricity. This is in fact a fairly easy process if you have constant wind and you can control the conditions of wind speed. Although a fairly clean process, cost and wind conditions pose a challenge for this technology.
The geothermal energy resources from inside the earth seem to be steadily available underground, in some cases it is used to heat and cool individual homes, but it can be used to power buildings with multiple dwellings. It seems to be a resource fairly easy to harness with the right geological conditions and necessary fiscal resources.
Another source of renewable energy is the biomass which utilizes solar energy stored in plants. In the past and still today many people utilize wood as a source of energy. In addition, sugar cane is squeezed and the liquid is fermented to produce alcohol that is then burned to generate power. In some cases sugar cane plants utilize the “bagasse”, the pulp of the sugar cane after squeezing the liquid to be burned and generate power to boil water to create steam. Some of our garbage could be used to be converted into biomass energy. Even though this source is available to some extent and could help with reduction of landfills, the burning of material releases heat into the atmosphere and other pollutants as well, contributing to the augmented pollution of our planet Earth’s environment.
Many of us have seen and enjoyed the waterfalls created for the purpose of generating hydraulic power. The damns are usually engineering wonders that many visit in sightseeing trips. Yet, do we ever think of a damn as stored energy? Or do we see the falls as part of the mechanism in generating electricity? I am sure if you are scientifically or technologically inclined that comes to mind. But how does it work? Hydraulic plants capture the energy of falling water and convert it into electricity. A turbine actually takes the kinetic energy of falling water and converts it into mechanical energy. Then a generator converts the mechanical energy into electrical energy. This electrical energy is then fed into electrical grids to be used in homes, business and industry.
Non-Renewable Energy Sources
An interesting fact is that we get most of our energy from non-renewable energy sources. These sources include fossil fuels such as oil, natural gas, and coal. Fossil fuels are called such because they are the remains of dead plants and animals that have been formed over millions of years by the action of heat from the Earth’s core and the pressure of rocks and soil. Other researched non-renewable energy sources are uranium and hydrogen.
Oil
“In January 2001 alone, the United States produced an estimated 181 million barrels of crude oil and imported 273 million barrels from other countries”-- How stuff works, 2004. We know that petroleum or oil, one of the fossil fuels, is utilized to manufacture many different items. The best known is gasoline which for industry and business constitutes a precious liquid that generates the combustion to power transportation devices critical in the operations of our economy. Also we can get heating oil, jet fuel, and kerosene which are good generators of combustion that we utilize for personal use as well as for industry or business. In addition, there are other things that we can obtain from oil such as crayons, plastics, synthetic fibers, and tires.
Natural Gas
Natural gas is pumped out of the ground it is found in the same deposits where we find oil. Although natural gas was once considered a waste product of oil production the increased need for less carbon emission energy sources and increased technology for the utilization of natural gas has made it a viable source of energy. We should keep in mind that this is a fossil fuel that does emit greenhouse gases. However, according to the World Energy Council (2001), natural gas compares favorably against oil and coal in terms of global warming potentials. Apparently, oil can contribute for 20% more carbon dioxide and coal can contribute 50% more than natural gas. This factual information makes natural gas a fairly cheaper and cleaner source of energy when compared to oil and coal.
Coal
Coal is a type of organic rock that contains concentrated amounts of carbon. Some forms of coal can generate as much as 24 million BTUs (British thermal units) per ton. Although this is a highly available source of fossil fuel it constitutes a high risk to the environment. Usage of coal has contributed to global warming which makes it a challenge for business, the government, scientist, and environmentalists as well.
