Alternative Energy for a Cleaner World
An Alternative Energy Future?
Energy is the basis of human life and plays an important role wherever man lives or works. The quality of life, living standards and prosperity of a nation varies in direct proportion with the increase in the way we use energy with hardly any activity or moment that is not dependent on some form of energy for its operation.
The electricity requirements of the world is increasing at an alarming rate, every moment of the day we are using more and more energy due to an increased and extensive use of electrical and electronic gadgets both at work and in the home. So there is considerable potential to develop different types of Alternative Energy Sources to help fuel our ever growing dependence on energy and especially on fossil fuel energy.
The Suns Energy Feeds the Earth
But what do we mean by “Alternative Energy”, what is alternative energy?. Most of us think of alternative energy as roof mounted solar panels turning the energy of the sun into either hot water or electricity. But alternative energy is much more than that. Some of these alternative energy sources are by no means new, as for hundreds of years people have used the wind, water and sun for all sorts of uses including cooking, heating, farming and transportation.
While some forms of modern alternative energies are really just new developments of long-existing and well established technologies, such as wind turbines for wind energy or water wheels for hydro energy, but other types of alternative energy are genuinely new such as nuclear, ethanol biofuels, and photovoltaics.
The expression “energy” is often used without a great deal of thought and is applied in various different contexts. In its simplest terms, Energy is the ability to do work, the ability to make things happen. But in reality, it does much more. Energy is one of our most valuable resources and has always existed in one form or another. Nearly all of the energy available to us here on Earth was initially derived from the energy created by the Sun, which is nothing more than one giant fusion reactor. But once this energy leaves the Sun, it is converted into other forms of energy on Earth such as heat and light that generates wind, rain, rivers, and waves which we can use as an alternative energy source.
The term “alternative energy” refers to any form of energy which is an alternative to the more traditional three fossil fuel sources of oil, natural gas and coal. But the expression of alternative energy sources is commonly used to compare petroleum oil and in all its various forms against other forms of renewable energy. While none of these “alternatives” appear to be completely equal to oil in terms of its flexibility and energy content, oil just like other forms of fossil fuel, is a finite resource and will eventually run out. Hence, the need to use alternative sources of energy.
The three types of fossil fuel energies of Coal, Oil and Natural gas are the most important fuels we use today and the modern world relies heavily on these non-renewable sources for the majority of its energy needs. But these sources of energy will not last forever and with a reduction in global fossil fuel reserves, an increasing threat to their continuing security, combined with their contribution to climate change which has proved to be a major cause of environmental issues and harmful carbon dioxide (CO2) emissions, we must now consider the alternatives.
Even if we had an unlimited supply of fossil fuels, using alternative energies is much better for the environment, the planet and human life generally. The advantages of Alternative Energy is that it is renewable, sustainable or potentially sustainable, and environmentally benign. We often think of alternative energy technologies as “clean” or “green” because they produce very few if any pollutants.
However, the disadvantages of alternative energy are their low density, higher initial investment costs and variability in its source requiring the need for energy storage or some form of alternative backup power such as a generator when the sun does not shine or the wind does not blow.
Realising that oil is finite in practical terms, there is increasing attention given to what alternative energy sources are available to replace oil. As the demand for alternative energy sources increases each year due to the need for clean and renewable sources of energy.
Alternative forms of energy are all around us in the wind, the waves and tides and in the energy from the Suns abundant resource of power. There are six main forms of alternative energy that exist now and which can be divided into two categories of either renewable or non-renewable energy sources of one or more of the following.
Renewable Energy: Renewable energy can be defined as energy which is obtained from natural and persistent sources of energy occurring in the immediate environment such as solar (sunshine) energy. This energy is constantly being replenished at a rate faster than it is being consumed, making this type of energy an “infinite resource”.
Renewable energy passes through the environment as a current (wind), electromagnetic radiation (sunlight) or as a flow (water), irrespective of there being a device to intercept or harness this power. Such energy may also be called “Green Energy” or “Sustainable Energy”.
Non-renewable Energy: Non-renewable energy on the other hand, is defined as energy obtained from non-renewable static sources of energy. These energy resources remain buried underground unless released by human interaction. Non-renewable energy sources are generally called fossil fuels which includes coal, petroleum oil, natural gas and some radioactive nuclear fuels.
This energy resource is being used up at a rate faster than it can be replenished by the Earth’s natural systems, making this type of energy a “finite resource”. Non-renewable energy is stored potential energy, and an external action is required such as combustion to initiate the supply of energy for practical purposes. Such energy supplies are generally called “Finite Supplies” or “Brown Energy”.
The most common “alternative energy” source available today is hydro-electric power followed by wind power and solar power. An overview of the various kinds of alternative energy follows but first we must differentiate between an alternative energy, and a renewable energy resource. Alternative energy refers to any form of energy which is an alternative to the traditional fossil fuels of oil, natural gas and coal. Renewable energy are the forms of alternative energy that are renewed by the natural processes of the Earth, such as sunlight from the sun or wind from the air, and so are therefore environmentally friendly.
While we intend in these alternative energy tutorials to cover all types of alternative energies and renewable energies, we will begin with an overview of renewable energy sources. The main six forms of renewable energy are:
- 1. Hydro Energy: The longest used form of alternative energy and power dating back thousands of years. Dams and water wheels use the potential and kinetic energy of water as a source of power to grind corn and produce flour. Hydro energy accounts for almost a fifth of all electricity generated worldwide by using dams and hydro-electric power generation. Harnessing the energy contained in water flowing down hill to a lower elevation, it is highly efficient but limited by the necessity of suitable natural resources such as mountains, lakes and gravity.
- 2. Solar Power: Sunlight contains thousands of times more available energy than humans could ever use, but harnessing it can be expensive. One common method is photovoltaic cells. They turn sunlight into electricity but only work at a maximum efficiency of little more than 20 percent. They are also expensive to manufacture and buy. Solar heating systems use flat panels to capture the suns warmth to heat domestic hot water with large commercial installations using mirrors to reflect the suns heat onto a central heat absorber for maximum efficiency.
- 3. Wind Energy: Another well established form of alternative power used for hundreds of years by millers and windmills. The sight of massive wind turbines gently whirring atop a large hill or on high ground is now becoming increasingly common. However, such turbines and associated wind farms has prompted many discussions amongst environmentalists, with some green activist arguing long lines of wind turbines scar the natural beauty of the countryside, produce environmental noise and can kill too many birds with their constantly rotating blades.
- 4. Wave and Tidal Energy: Although still in its development stage, these are two ocean-based technologies with high potential for providing a clean, free alternative energy source in the future. Wave power uses the kinetic energy of the ebbing and flowing of the oceans waves and tides by trapping water in tidal barrages or through underwater tunnels, which is then used to rotate tidal turbines. Tidal power also uses large turbines fixed to the sea bed or just below the surface of the waves to capture the energy from strong tidal currents.
- 5. Nuclear Energy: While not strictly a renewable energy source, nuclear energy can be thought of as an alternative form of energy compared to fossil fuels. There is a limited amount of Uranium available globally which has to be both mined and refined so is considered by many as a non-renewable energy source, but with the design of modern nuclear reactors becoming safer and more efficient than those used in the past, nuclear energy is becoming powerful enough to have a real impact on the reduction of fossil fuel usage.
- 6. ”Alternative” Fossil Fuels: Many believe that there is enough oil, coal and natural gas resources left in the Earth to last us at least another 500 years and that burning fossil fuels more cleanly and efficiently is the way forward. Suggestions include “storing” the harmful carbon dioxide emissions deep underground, mixing and co-firing coal with biomass, as well as improving the way we excavate and burn fossil fuels. To many this is the most feasible way of saving our non-renewable energy supplies and the environment.
Is Alternative Energy Enough
Our interpretation of Alternative Energy is better because “alternative energy sources” or “alternative energy supplies” could have a different meaning much broader than simply Alternative or Renewable Energy. Alternative energy is all about energy sources that are distinct or an alternative too, or a replacements of, conventional fossil fuels. Most sources of “alternative energy” depend on obvious, natural sources of energy and there is nothing new about these energy sources.
People have always used the sun to light their homes, dry their clothing or heat their food for thousands of years, but many alternative or renewable energy sources, especially hydroelectric power, wind, and solar power, are already providing significant amounts of energy or at least are capable of providing significant amounts of green energy in the near future. These energy sources have many advantages over fossil fuels, but they also have their limitations.
Can Alternative Energies fill the gap?, there are no easy answers to the energy problem, even the best energy technologies for the future may be complicated, dangerous, and expensive. However, one thing is certain all ways of making energy harm the Earth to some extent. Therefore, no matter where our energy comes from, we should not waste it.
Living a more energy efficient life is easy as scientists and engineers work on more efficient refrigerators, cars, lights, and other devices etc. We can all do our bit to save a significant amount of energy just by turning “off” the lights, TV and other electrical devices when we are not using them. Over time, we can all make different choices about how much energy to use and how to use it. A more energy efficient world is a world that is easier to supply with energy, whatever the source.
In the next tutorial about Alternative Energy, we will look at the different types of fossil fuels currently being consumed.