Renewable Energy Sources Today: A Review
The emergence of modern-day developed economies depended heavily on the availability of cheap and abundant energy, but the planet’s oil reserves, which supplies over 35% of the world’s energy needs, are projected to be depleted within a hundred years (Balat 19). As this resource is depleted, demand will increase and drive prices to unheard of levels, thereby threatening the stability of economies in some of the most powerful nations the world. To avoid a catastrophic meltdown of what is now a global economic engine; governments worldwide have begun to invest in developing and promoting the use of renewable forms of energy. Although reducing fossil fuel use to lower green house gas emissions is a more laudable goal, it seems likely that economic incentives will be the primary driving force behind renewable energy development and implementation. This article reviews the various types of renewable energy in use today that will likely help reduce our dependence on fossil fuels.
Sources of solar energy can be divided into direct or indirect. Direct solar energy converts photons produced by the sun directly into either electricity or heat. The primary indirect forms of solar energy (energy carriers) are created by the power of the sun and include biomass, wind, ocean currents, and hydropower.
Direct Solar Energy
Passive Solar Heating
Passive solar heating captures the energy contained in direct sunlight to heat water, cook food, dry clothing or agricultural products, heat the interiors of buildings, provide air-conditioning, power desalination and water purification projects, and generate electricity. Given that building structures consume 35.3% of energy worldwide (Chan, Riffat, and Zhu 781), the development and use of passive solar technology will become critical to relieving our dependence on fossil fuels.
Photovoltaic cells are able to directly convert solar photons into electricity, because the photons are have enough energy to free electrons on one side of a light-absorbing material, thereby creating a charge differential. A single cell doesn’t produce a significant amount of power, but when linked together in arrays they produce enough to energy to support the needs of whole households and neighborhoods. The primary limitation is the cost, which is typically more than five times higher than hydropower, geothermal, or wind (Balat 20). Concerns about cost, reliability, and performance explains why photovoltaic cells produced only 1.8 GWh (Balat 25) of the 3,157,000 GWh of all electricity produced by renewable energy sources in 2004 (Balat 19). In spite of the high cost, the annual growth rate in photovoltaic use between 2000 and 2004 was an unprecedented 60% (Balat 25).
Solar Energy Carriers
Solar energy drives weather patterns, which in turn carries precipitation to higher elevations. Solar energy is thereby stored in the form of mountain snow packs and watersheds, which can be harvested by hydroelectric power plants positioned on a river or at the base of a reservoir. Because of the low cost and reliability of hydropower, close to 89% of all electricity produced by renewable energy sources comes from hydroelectric power plants (Balat 21). The annual growth of hydroelectric power is low compared to wind and photovoltaic cells, averaging between 1-2% annually. Market saturation in developed countries, environmental concerns, and population displacement contribute to the slow growth of hydroelectric plants worldwide.
Wind turbines are second only to hydropower in terms of cost and reliability and represent one of the fastest growing renewable energy sectors. In 2004 alone, over 6000 wind turbines, with an average capacity of 1.25 MW, were put into use worldwide (Balat 23). On a global scale though, wind turbines contribute only 0.5% of all electricity consumed (Balat 21). Given the annual growth rate in wind turbine capacity, which was close to 29% between 1994 and 2004, the contribution from wind energy should steadily increase. Currently, the vast majority of wind turbine capacity is located in only a few countries, including Germany, Spain, Japan, Italy, and the United States.
Almost without exception, all living matter derives most of its energy from the sun and stores it through carbon fixation. Traditional methods of converting solar energy into a useable form include the burning of firewood, straw, and animal dung for cooking and warmth, which still represents a major energy sourced in undeveloped countries. In developed countries the sources of biomass include agricultural and forestry residues, and municipal waste. Although still an important source of energy in developed economies, biomass provides a much smaller share of the energy consumed when compared to third world economies. The global energy contribution of biomass is around 9.5%, which represents 67.9% of the energy supplied by renewable energy sources (Balat 18). Biomass is converted to useable energy through combustion to generate heat, anaerobic digestion to produce methane, oil extraction for biofuels, or gasification to produce high grade fuels (Panwar, Kaushik, and Kothari). Unfortunately, the use of biomass generates greenhouse gases at almost the same rate as fossil fuels and therefore represents a threat to the environment.
The fourth biggest producer of renewable energy in the world is geothermal energy, which provides about 0.5% of the world’s energy needs (Philips 2415). Geothermal energy exploits the heat stored within the earth, which was formed by the heat already present in the matter prior to the formation of earth, created as gravitational energy was spent as the matter combined to form the earth, and by ongoing radioisotope decay. From a human perspective, geothermal energy is essentially limitless.
Energy is produced by either tapping underground hot water reservoirs or pumping surface water deep into a borehole to heat it. If the temperature is hot enough to produce steam then electricity can be generated, otherwise it can be used as a heat source. There are several important limitations to using geothermal energy. For example, the steam derived from a geothermal reservoir can sometimes contain enough greenhouse gases to rival that produced by fossil fuels. The steam may also contain toxins, like mercury, boron, and radon. Other potential environmental hazards include water pollution, damage caused during the construction and operation of a geothermal power plant, soil erosion, and noise pollution. Still, with an annual rate of growth around 3.7% there is continued interest in exploiting this renewable energy source (Balat 21).
With the world’s governments racing against time to have renewable energy sources online before fossil fuel prices become untenable, public investment into this energy sector is expected to continue to increase. With a goal of supplying 50% of global energy needs by the year 2040 (Panwar, Kaushik, and Kothari 1514) considerable investment into renewable energies will be required. Global photovoltaic, geothermal, and wind energy-producing capacity is expected catch up to hydropower by 2040, even though hydroelectric capacity is expected to increase by 17-fold during the same period. These projections reflect a dramatic shift in renewable energy markets and technology that is expected to occur over the next 30 years, which should reduce our dependence on fossil fuels. Hopefully this transformation will lower the negative impact of energy production on the environment, but this isn’t assured because the exploitation of some renewable energy sources can also damage the environment.
Balat, M. (2009). Development of worldwide green electricity in the past decade. Energy Sources, Part B, 4, 17-33.
Chan, Hoy-Yen, Riffat, Saffa B., and Zhu, Jie. (2010). Review of passive solar heating and cooling technologies. Renewable and Sustainable Energy Reviews, 14, 781-789.
Panwar, N.L., Kaushik, S.C., and Kothari, Surendra. (2011). Role of renewable energy sources in environmental protection: A review. Renewable and Sustainable Energy Reviews, 15, 1513-1524.
Phillips, Jason. (2010). Evaluating the level and nature of sustainable development for a geothermal power plant. Renewable and Sustainable Energy Reviews, 14, 2414-2425.
Get Professional Assignment Help Cheaply
Are you busy and do not have time to handle your assignment? Are you scared that your paper will not make the grade? Do you have responsibilities that may hinder you from turning in your assignment on time? Are you tired and can barely handle your assignment? Are your grades inconsistent?
Whichever your reason is, it is valid! You can get professional academic help from our service at affordable rates. We have a team of professional academic writers who can handle all your assignments.
Why Choose Our Academic Writing Service?
- Plagiarism free papers
- Timely delivery
- Any deadline
- Skilled, Experienced Native English Writers
- Subject-relevant academic writer
- Adherence to paper instructions
- Ability to tackle bulk assignments
- Reasonable prices
- 24/7 Customer Support
- Get superb grades consistently
Online Academic Help With Different Subjects
Students barely have time to read. We got you! Have your literature essay or book review written without having the hassle of reading the book. You can get your literature paper custom-written for you by our literature specialists.
Do you struggle with finance? No need to torture yourself if finance is not your cup of tea. You can order your finance paper from our academic writing service and get 100% original work from competent finance experts.
While psychology may be an interesting subject, you may lack sufficient time to handle your assignments. Don’t despair; by using our academic writing service, you can be assured of perfect grades. Moreover, your grades will be consistent.
Engineering is quite a demanding subject. Students face a lot of pressure and barely have enough time to do what they love to do. Our academic writing service got you covered! Our engineering specialists follow the paper instructions and ensure timely delivery of the paper.
In the nursing course, you may have difficulties with literature reviews, annotated bibliographies, critical essays, and other assignments. Our nursing assignment writers will offer you professional nursing paper help at low prices.
Truth be told, sociology papers can be quite exhausting. Our academic writing service relieves you of fatigue, pressure, and stress. You can relax and have peace of mind as our academic writers handle your sociology assignment.
We take pride in having some of the best business writers in the industry. Our business writers have a lot of experience in the field. They are reliable, and you can be assured of a high-grade paper. They are able to handle business papers of any subject, length, deadline, and difficulty!
We boast of having some of the most experienced statistics experts in the industry. Our statistics experts have diverse skills, expertise, and knowledge to handle any kind of assignment. They have access to all kinds of software to get your assignment done.
Writing a law essay may prove to be an insurmountable obstacle, especially when you need to know the peculiarities of the legislative framework. Take advantage of our top-notch law specialists and get superb grades and 100% satisfaction.
What discipline/subjects do you deal in?
We have highlighted some of the most popular subjects we handle above. Those are just a tip of the iceberg. We deal in all academic disciplines since our writers are as diverse. They have been drawn from across all disciplines, and orders are assigned to those writers believed to be the best in the field. In a nutshell, there is no task we cannot handle; all you need to do is place your order with us. As long as your instructions are clear, just trust we shall deliver irrespective of the discipline.
Are your writers competent enough to handle my paper?
Our essay writers are graduates with bachelor's, masters, Ph.D., and doctorate degrees in various subjects. The minimum requirement to be an essay writer with our essay writing service is to have a college degree. All our academic writers have a minimum of two years of academic writing. We have a stringent recruitment process to ensure that we get only the most competent essay writers in the industry. We also ensure that the writers are handsomely compensated for their value. The majority of our writers are native English speakers. As such, the fluency of language and grammar is impeccable.
What if I don’t like the paper?
There is a very low likelihood that you won’t like the paper.
- When assigning your order, we match the paper’s discipline with the writer’s field/specialization. Since all our writers are graduates, we match the paper’s subject with the field the writer studied. For instance, if it’s a nursing paper, only a nursing graduate and writer will handle it. Furthermore, all our writers have academic writing experience and top-notch research skills.
- We have a quality assurance that reviews the paper before it gets to you. As such, we ensure that you get a paper that meets the required standard and will most definitely make the grade.
In the event that you don’t like your paper:
- The writer will revise the paper up to your pleasing. You have unlimited revisions. You simply need to highlight what specifically you don’t like about the paper, and the writer will make the amendments. The paper will be revised until you are satisfied. Revisions are free of charge
- We will have a different writer write the paper from scratch.
- Last resort, if the above does not work, we will refund your money.
Will the professor find out I didn’t write the paper myself?
Not at all. All papers are written from scratch. There is no way your tutor or instructor will realize that you did not write the paper yourself. In fact, we recommend using our assignment help services for consistent results.
What if the paper is plagiarized?
We check all papers for plagiarism before we submit them. We use powerful plagiarism checking software such as SafeAssign, LopesWrite, and Turnitin. We also upload the plagiarism report so that you can review it. We understand that plagiarism is academic suicide. We would not take the risk of submitting plagiarized work and jeopardize your academic journey. Furthermore, we do not sell or use prewritten papers, and each paper is written from scratch.
When will I get my paper?
You determine when you get the paper by setting the deadline when placing the order. All papers are delivered within the deadline. We are well aware that we operate in a time-sensitive industry. As such, we have laid out strategies to ensure that the client receives the paper on time and they never miss the deadline. We understand that papers that are submitted late have some points deducted. We do not want you to miss any points due to late submission. We work on beating deadlines by huge margins in order to ensure that you have ample time to review the paper before you submit it.
Will anyone find out that I used your services?
We have a privacy and confidentiality policy that guides our work. We NEVER share any customer information with third parties. Noone will ever know that you used our assignment help services. It’s only between you and us. We are bound by our policies to protect the customer’s identity and information. All your information, such as your names, phone number, email, order information, and so on, are protected. We have robust security systems that ensure that your data is protected. Hacking our systems is close to impossible, and it has never happened.
How our Assignment Help Service Works
1. Place an order
You fill all the paper instructions in the order form. Make sure you include all the helpful materials so that our academic writers can deliver the perfect paper. It will also help to eliminate unnecessary revisions.
2. Pay for the order
Proceed to pay for the paper so that it can be assigned to one of our expert academic writers. The paper subject is matched with the writer’s area of specialization.
3. Track the progress
You communicate with the writer and know about the progress of the paper. The client can ask the writer for drafts of the paper. The client can upload extra material and include additional instructions from the lecturer. Receive a paper.
4. Download the paper
The paper is sent to your email and uploaded to your personal account. You also get a plagiarism report attached to your paper.
PLACE THIS ORDER OR A SIMILAR ORDER WITH US TODAY AND GET A PERFECT SCORE!!!