Alternative energy

Posted: October 17th, 2013

Name:

Course:

Lecturer:

Date:

Alternative energy

Introduction

Since the beginning of industrialization, people have used energy from fossil fuels in abundance. Fossil fuels are carbon based and they include coal and natural gas. The fossil fuels emit carbon when they are burned. Many environmentalists believe that the increase in carbon levels contributes to global warming. They therefore propose the development of other sources of energy, which will not increase the level of carbon in the atmosphere. Alternative energy therefore refers to other sources of energy, which are not based on fossil fuels. Although most of the alternative energy sources are renewable, others are not. Fossil fuels have been used for a long time and they are non-renewable. This has prompted people to look for alternative sources of energy, to cater for the shortage that may arise once the fuels are depleted. There are different sources of alternative energy that have been developed over the years, and they include solar, geothermal, hydroelectric, wind power, biomass and hydrogen. They have many benefits over fossil fuels, but they also have several disadvantages.

1. Solar Energy

Solar energy comes from the thermal energy from the sun. It is the most abundant and renewable source that is available in most parts of the world. Most of the alternative sources of energy used today, such as biomass, wind, hydro and ocean energy get their energy from the sun (McKinney 216). Solar energy has been used for a long time for warming, cooking and heating. However, people have not been quick to develop this source of energy. This has however changed with the increasing awareness of the need for alternative energy. Photovoltaics are used to convert the solar energy to electrical energy. Solar energy can be stored in batteries and used at night or for temporary periods when there is no sun.

Advantages

There are several advantages of using solar energy. The sun is an inexhaustible source of energy that is available naturally. It is clean energy, meaning that it does not pollute the environment (Smith and Taylor 14). Solar energy is free, and the only investment needed is the system that will convert the energy. Countries do not have to rely on a few select countries to get their fuel. The energy is not controlled by anybody, and people with the relevant technology can use it. Another advantage is that it is cost effective, especially in the end. Once a person has all the materials needed, he or she does not have to worry about other costs. People do not have to worry about increase in fuel costs. This makes it especially useful and beneficial for commercial use, since companies cut their fuel costs substantially. Solar systems produce energy quietly, unlike most sources of alternative energy. Rural and remote areas that were once not covered by national grinds can now get electricity from solar energy. The systems require little maintenance and they are durable.

Disadvantages

One of the major disadvantages of solar energy is that it is available at certain seasons in many countries. It depends on time and weather conditions. Countries, which have winter and fall seasons, cannot benefit from the solar energy during those seasons. Another disadvantage is that it is costly to implement. Although the sun’s energy is free, the materials and resources required to convert the energy is expensive. The solar cells used to convert solar energy are a source of pollution. Many poisonous chemicals such as arsenic and hydrofluoric acid are used to manufacture the solar cells, and they cause environmental pollution (McKinney 223). Although the solar panels do not require a lot of maintenance, the solar cells have to be replaced after about thirty years. The batteries used to store the sun’s energy for future use are expensive and can be harmful.

2. Wind Energy

Wind energy has been used for a long time. Windmills convert wind energy into mechanical energy. Wind turbines convert the energy from the wind into electrical or mechanical energy. Some areas are extremely windy whereas others do not get enough wind. Wind does not flow smoothly on the earth’s surface. The friction of the wind creates ground drag, which in turn slows the speed of the wind. Objects and buildings will also affect the speed of wind. Flatter regions such as water bodies and plains experience less ground drag, hence there will be more wind in these areas, than rougher surfaces such as forests and cities (Chiras 25). Wind may not be available throughout the day, even in windy places. It can be stored in batteries when it is abundant; to be used when there is no wind. Some systems make it possible for the energy to be stored in the electric grind, where it is used when the winds fail. Solar and wind energy complement each other well. Some wind systems can be used together with the solar system. People can therefore combine the two sources to ensure that they have energy regardless of the time of day, or season.

Advantages

There are several advantages of using wind energy. It is a free and an inexhaustible source of energy. It does not have any controls or regulations. No single country can control the amount of wind blowing to other countries. Countries, which have an abundance source of wind, do not have to worry about the costs or price increases. Wind energy does not harm the environment in any way since it does not produce any emissions. This helps in reducing global warming and reducing pollution. Wind energy can reduce the dependence on natural gas. Natural gas is not renewable although it is one of the major sources of fuels in many countries (Chiras 12-13). Wind energy does not require much space, since the turbines do not stand on huge tracts of land. This is especially the case in small-scale production meant for residential use. Wind energy is especially useful in remote and rural areas. People in these places can produce their own energy using minimal resources.

Disadvantages

Some people oppose using wind energy for several reasons. They claim that it is a visual pollutant. They do not like the windmills and turbines since they are aesthetically appealing. Another disadvantage is that the energy depends on the geographical location of the region. Some regions cannot harness wind energy because they do not have enough wind. The strength of the wind depends on several factors and it is not always constant. Strong winds can damage the windmills and turbines. Another disadvantage is that it can be harmful to birds. Some birds have been killed as they have flown directly to the turbines. Some people complain about noise pollution that is produced by the turbines. The turbines produce some noise, which increases in intensity as the wind increases (Chiras 6-11).

3. Biomass Energy

Biomass energy is derived from living plants and the waste from humans. It is one of the most developed sources of energy. Some countries, such as Brazil, are specializing in the production of biomass to use as fuels in vehicles. Biomass energy is used for many different applications such as transportation, heating and electricity generation. There are different forms of biomass energy. They include biogas such as methane, solid biofuels, liquid biofuels, and energy crops. The most commonly used liquid biofuels are ethanol and biodiesel. Ethanol is produced from sugarcane, corn and other starchy crops. Biodisel on the other hand is derived from vegetable oils and animal fat (Brauch382). Increase in biomass energy has increased tremendously over the years. This is because many people see it as an alternative to fossil fuels.

Advantages

Using biomass energy has several advantages. The use of biomass energy is not restricted to selected countries. Any country can produce biomass energy because the materials needed to do so are readily available in many countries. Another advantage is that it is a way of taking care of the environment. It is a way of controlling and taking care of organic waste, such as manure, since the waste is converted to energy. Energy from biomass energy is cost effective. It is cheaper compared to other sources of energy such as fossil fuels. Biomass is a preferred source of energy compared to other alternative sources of energy because of its wide application and easy transition. It can be used in place of fossil fuels. It is however beneficial since it does not pollute the environment to the same degree as the fossil fuels. Ethanol and biodiesel are beneficial because of their ability to blend with fossil fuels. This means that there is less transitional cost, since the existing machinery and vehicles do not need to be modified.

Disadvantages

Unlike other sources of alternative energy, the production of some types of biomass energy such as ethanol and methane can harm the environment, although to a lesser extent than the fossil fuels. Ethanol is made from plants such as sugarcane, corn and soybeans. Burning these crops to produce energy causes pollution and the plants emit greenhouse gases (Smith and Taylor 18). Another disadvantage is that it requires a lot of space. Since many forms of biomass energy depend on plants, large tracts of land will have to be cleared when planting the crops to be used for biomass energy. Increased demand for the biofuels has resulted on greater competition of land resources. Most farmers cannot decide whether they will produce corn to be used for fuel, animal feed or whether they will produce food for human consumption (Brauch380). Some countries might find the production of biomass energy on large-scale measures expensive to implement. Biomass energy requires good storage facilities. Some types of biomass fuels cannot be stored the same way as fossil fuels. Some people oppose the use of biomass energy on moral grounds. This is because, as some countries grow food crops such as corn and soybeans to be used as biofuels, other countries around the world suffer because they do not have enough food. Adoption of some biofuels requires the use of new technology in different machines. Some of the machines will have to be modified so that they can use the fuels.

4. Geothermal Energy

Geothermal energy is stored beneath the ground, in the earth’s crust, and in hot dry rocks (Smith and Taylor 18). The earth’s core is very hot, and this is caused by the decaying radioactive particles. Some locations in the earth’s surface have underground water and once they are exposed to the heat, they produce water and steam. These are the best locations to extract geothermal energy since less energy will be used and it will therefore be less costly. Although many regions can harness geothermal power, it is most applicable in areas where hot magma from underground is close to the surface and along the plate margins (McKinney 227)

Advantages

Geothermal energy is one of the cleanest sources of energy since it does not have any emissions. The provision of geothermal energy does not depend on seasons. The energy source is available throughout.

Disadvantages

Although geothermal is clean energy, it emits gases such as methane, ammonia, and hydrogen sulfide. Some of these gases produce a bad odor and they can be harmful. Methane is one of the most common greenhouse gases (Kowalski 181). Geothermal energy releases a lot of heat that can be harmful to the environment. This heat can cause thermal pollution, which can in turn kill plants and animals, and destroy the natural ecosystem. A lot of water is required during the production of geothermal energy. Water is one of the scarce resources and every measure should be taken to ensure that it is conserved. The water is used for cooling and condensing (McKinney 228).

5. Hydro Energy

Rivers and other sources of running water can be used to produce hydropower. Hydroelectric energy has been used for a long time, using waterwheel technology. Hydropower is a renewable source of energy. This source of energy can also be captured from dams, when used on a larger scale. It is especially used for electricity generation. Hydro energy is obtained when the force of moving water turns a turbine, and the turbine rotates the generator. When building large dams, it is important to consider the location and the source of the water. The production of hydroelectric power can have diverse and negative consequences for the environment, and for people living in the region.

Advantages

Hydropower is a reliable source of energy once the best location has been identified. It is cost effective once the dams have been built. Most countries have developed hydro energy, which they use for the generation of electricity. Technology in the production of hydro energy has improved, and this has improved the methods used when generating electricity. When used in a large scale, it benefits more people than other sources of energy. It is a clean source of energy and it does not pollute the environment. It does not release carbon dioxide or produce emissions that harm the environment (McKinney 209). The dams built for the generation of hydropower can be used for other purposes such as irrigation, control of flooding, navigation and fishing (McKinney 212). The water used for the production of hydro energy is stored in dams, and this makes it a renewable source of energy. It is easy for a person to adjust the water flow and the electricity output. This is especially convenient when the water supply is low. Reducing the output of electricity will conserve the remaining water.

Disadvantages

Hydropower can only be used in areas where there is a lot of water, which is available throughout the year. The initial costs can be expensive since a lot of funding is required to build the dams. The environmental costs can also be high during the construction of dams. A lot of fossil fuel is used during construction. It requires a lot of space, and this has sometimes resulted in the displacement of the local communities, clearing and destruction of forests and other natural habitats, and disturbing the ecosystem. Another disadvantage is the disturbance and change in the flow of water. It disrupts the flow of water when the waterfalls and rivers are used. Since the water is harnessed upstream, the people in the lower ends will not get enough water. It can also cause flooding when the dams are not managed properly, or in case of any fault during construction. Unanticipated flooding can occur when it rains heavily and the running rainwater does not get a free outlet. The water in dams is stagnant, and it can attract mosquitoes, flies, snails, which will turn cause diseases.

6. Ocean energy

People have found different ways of obtaining energy from the ocean using tides, waves and difference in water temperatures. Tidal energy generates electricity by using energy from the ocean currents, and the difference between high tide and low tide. Wave energy is converted to electricity. It is obtained from the surface waves and pressure fluctuations. Ocean energy thermal conversion obtains power from the difference between water temperatures. The surface waters have a different temperature from deeper ocean waters. Ocean energy is still in the developmental stages, and it is not used by many countries. Electricity can be converted using the closed cycle, open cycle or the hybrid system. Wave energy can be converted to mechanical energy using channel systems, float systems or the oscillating water column systems. The channel systems channel the waves to the reservoirs, where they are converted to energy. Float systems use hydraulic pumps, and the oscillating water column systems use pressure (Renewable Energy World).

Advantages

The different forms of ocean energy makes them more reliable than some alternative sources of energy. Oceans make up more than 70% of the earth’s surface, and there is therefore a huge potential for the growth of alternative fuels. Thermal energy is constant since it does not depend on the tides or waves. Because of the large surface areas, oceans are able to convert most of the sun’s energy to thermal energy. Tidal energy is considered a renewable source of energy because the tides depend on the gravitational pull from the sun and the moon. These are forces of nature, which cannot be controlled, and they are not expected to end. Energy from the ocean is clean, and it does not emit any harmful and toxic gases. It is therefore environmentally friendly. Although tides fluctuate, they are considered reliable because they are predictable, and this makes it easier to construct and develop systems (Energy Informative).

Disadvantages

The major disadvantage of ocean energy is that it is applicable to oceanic areas. Another disadvantage is that it requires a lot of investment in terms of the resources used to convert the waves and tides into usable energy (Smith and Taylor 26). Tidal energy is not applicable in all areas since the difference between the low tide and the high tide is not enough to produce energy. The development of ocean energy can disrupt marine life and disturb the marine ecosystem.

Summary and Conclusion

Most of the alternative sources of energy are renewable and clean. They do not pollute the environment, since they do not have emissions. However, it is clear that all the alternative energy sources have some level of pollution. Some of the alternative sources such as solar, wind, water and different forms of biomass have been used for a long time. They were however abandoned during the industrialization period. Environmental concerns and the need to have clean energy has been one of the major reasons for their comeback. Individuals and countries are also concerned about the increasing cost of fossil fuels.

Some alternative sources of energy are expensive because they have not been developed, and are not used extensively. Once people begin to use these alternative sources, the technology used to create the systems will develop, and cheaper methods will be sought. It is important for people to weigh the benefits and costs of using some alternative sources of energy before they invest in them. This is because they can be expensive to implement. Energy storage is one of the major challenges facing the development and use of alternative energy. Alternative energy will benefit people in the end, if they are managed in the right way.

Works Cited:

Brauch, G. Hans, John Grin, Czeslaw Mesjasz, Patricia K. Mbote, Úrsula O. Spring. Facing Global Environmental Change: Environmental, Human, Energy, Food, Health and Water Security Concepts. Germany: Springer, 2009. Print

Chiras, Dan. Wind Power Basics: A Green Energy Guide. Canada: New Society Publishers, 2010. Print

Energy Informative. Tidal Energy Pros and Cons. 3 Oct 2011. Web. March 7 2012.

Kowalski, M. Kathiann. Alternative Energy Sources. Tarrytown, NY: Marshall Cavendish, 2010. Print

McKinney, L. Michael, Robert M. Schoch, Logan Yonavjak. Environmental Science: Systems and Solutions. Sudbury, MA: Jones & Bartlett Learning, 2007. Print

Renewable Energy World. Ocean Energy. Web. March 7 2012.

Smith, A. Zachary and Taylor, D. Katrina. Renewable and Alternative Energy Resources: A Reference Handbook. Santa Barbara, CA: ABC-CLIO, 2008. Print