Sources of energy have been important since the times of antiquity. Ancient civilizations in western countries were characterized by the industrial revolution. During this period, most energy sources were discovered and used to improve the industrial productivity. Energy sources are classified into two major categories; renewable or non-renewable (Twidell, 2006).
Whereas renewable sources cannot be depleted with time, non renewable sources can be depleted over time. Examples of renewable sources of energy are; solar, geothermal power, wind, nuclear energy, hydropower, and biomass. Fossil fuels and coal are the most common sources of non-renewable energy. This paper outlines the existence, environmental impacts and market trends of various renewable sources.
Renewable energy sources are naturally occurring sources. They can be replenished again and again. They are regarded eco-friendly as opposed to fossil fuels (Twidell, 2006). Various renewable energy sources are discussed next. Solar energy refers to the energy derived from the sun.
It can be used directly or indirectly for the generation of electricity. Direct generation of electricity from the sun involves the use of photovoltaic cells (Maczulak, 2010). Indirect generation employs the use of concentrators that tap heat energy required to heat water and produce steam. The steam is then used to run generators. Biomass energy refers to the energy derived from the combustion of either animals or plants.
Use of wood and biogas is rampant in many regions. Biomass is not only used for heating and cooking but also for used to generate electricity. Wood waste or paper waste are often burnt to produce steam vital for generation of electricity (Maczulak, 2010). Hydropower energy, on the other hand, refers to the energy derived from moving water.
Water is made to drop from a high level so that it can be used to rotate turbines resulting in the generation of electricity. Here, mechanical energy is converted to electrical energy. Geothermal energy is derived from the crust of the earth.
Deep wells are used to bring superheated steam onto the earth’s surface. The steam is used to turn turbines for electricity generation. Wind energy is derived from moving air. High speed winds rotate blades that generate electricity. Wind turbines and mills are used to harvest maximum wind energy (Solway, 2010).
Issues of global warming have initiated endless debates regarding how the issue can be addressed adequately (Clarisse, 2009). Fossil fuels have been attributed to increased carbon-dioxide emission. It is important to note that about 20% of the world energy sources come from renewable sources (Clarisse, 2009).
Renewable sources are regarded as the only option available in checking the increasing effects of global warming. However, some renewable energy sources have some negative environmental ramifications. Solar energy ranks best in terms of minimizing global warming (Clarisse, 2009).
Hydropower energy is usually dictated by the velocity and head of the water. Reduction of either of these parameters minimizes the energy produced. The source has negative impact on aquatic ecosystems. For instance, it is feared that salmon may be endangered in Columbia River due to presence of hydroelectric facilities (Abbasi, 2008).
The presence of turbine blades poses a threat to these endangered species of fish. Biomass energy has always been an air pollutant. In addition, there have been serious objections regarding the use of land to cultivate energy crops (Maczulak, 2010).Wind energy is only realized in areas where there are no trees. The establishment of wind energy plants may necessitate the clearing of forests.
This development may bring about land-use conflicts. Massive logging to pave way for such projects may lead to serious cases of desertification. Birds such as hawks and eagles have recently been killed by rotating blades. Geothermal energy is usually characterized by smelly emissions. The heavy metals or gases released from geothermal plants may negatively affect the health and lives of neighboring people (Abbasi, 2008).
Renewable energy sources bear different costs in terms of installation, operation and maintenance. It is important to note that most renewable sources are sustainable. Some such as the nuclear energy require a wide capital base to set up. Nuclear plants require radioactive waste and storage systems that are expensive to set up (Abbasi, 2008).
However, the amount of energy produced from nuclear plants is more than what is produced by the other sources. The short-term costs of setting up a nuclear plant may be high in the short term but low in the long term. Similarly, wind energy is gaining popularity in most countries. The maintenance costs are decreasing thereby reducing the short term costs (Sorensen, 2004).
However, the fact that the energy realized is far below the demand makes it expensive in the long term. All renewable energy sources carry with them their merits and demerits.
The increasing energy demand of renewable energy will automatically favor the growth of sources that have low long-term costs as opposed to those with low short-term costs. The period required to realize the long run benefits varies from one energy sector to another (Sorensen, 2004).
Supply and demand are major market forces. Renewable energy sources are also subject to varying demand and supply. Whereas the supply of some is high due to reduced cost of production, the supply of some is low due to elevated production costs. It is expected that use of renewable sources will increase drastically in the next 20 years (Panwar, 2007).
Economic, political and technological factors influence the demand and supply of renewable energy sources. Economic factors such as regional and national trade relations, taxation, tariffs and cost of production may influence the nature of supply realized. Similarly, high costs of fossil fuels, environmental degradation by fossil fuels, and technological innovations may increase the demand for fossil fuels.
The cost of raw materials required for the production of renewable energy may also dictate the nature of demand or supply observed (Panwar, 2007). Nuclear energy production, for instance, requires enough deposits of uranium. Lack of this mineral may lead to outsourcing. This makes the demand for nuclear energy low due to the high costs and unavailability of raw materials.
It is however important to note that growth in energy demand has not been consistent causing a phenomenon of energy intensity. Energy intensity has been due to adoption of different technological innovations (Panwar, 2007).
The management and maintenance of renewable energy production may be in the short run or long run (Solway, 2010). In the short run, the law of diminishing returns applies. Varying units of input such as raw materials made to fixed variables like capital results in variation in the total output. The output increases at first but later decreases. This is followed by a decline in marginal and later average product.
Fixed variables of production are under-utilized in short run productions. The effects of globalization are making managers to adopt the long run models of production. In the long run, all production factors are regarded as variables.
Returns to scale is a term used to describe the behavior of a business organization to changes in factor inputs. It is important that the supply and demand factors are put into consideration to make the renewable energy business-viable and sustainable.
References
Abbasi, S. (2008). Renewable Energy Sources and their Environmental Impact. New Delhi: PHI Learning Private.
Clarisse, F. (2009). Renewable Energy Sources: A Change to Combat Climate Change. Alphen aan den Rijn: Kluwer Law International.
Maczulak, A. (2010). Renewable Energy: Sources and Methods.New York: Facts On File.
Panwar, L. (2007). Renewable Energy Sources for Sustainable Development. Pitam Pura, New Delhi: New India Pub. Agency.
Solway, A. (2010). Renewable Energy Sources. Chicago, Ill.: Raintree.
Sorensen, B. (2004). Renewable Energy: Focus on its Physics, Use, Environmental.
impacts, Economy, and Planning Aspects. Amsterdam; Boston: Elsevier Academic Press. Twidell, J. (2006). Renewable Energy Resources. Taylor & Francis.