Renewable Energy Sources on Flight for a Better Society
Renewable energy sources are often associated with green technology because of their minimal environmental impact compared to fossil fuels. Renewable resources do not produce carbon-based warming and polluting agents into the atmosphere. On the contrary, the financial cost of its applications is not always cheap, and is most of the time requires huge investment but when the long-term benefits and profits are foreseen, the enormous funds will surely be worth. In addition, the utility of renewable energy supports a more sustainable use of finite sources of energy. With renewable energy sources, the dependence on fossil fuels can be minimized, or even impeded (Leipoldt).
The three major forms of renewable energy being harnessed in the society nowadays are Wind Energy, Solar Energy, and Biomass (Lenkefi).
Wind energy has been utilized since the early ages through the use of windmills. Initially harnessed centuries ago, early windmills were used to power millstones, pumps, and forges (AES 2003). Today, machines called wind turbines generate electrical energy by harnessing the power in wind. Wind turbines are like aircraft propeller blades which rotate through the winds motion the rotation then powers an electric generator which supplies an electric current. Wind speeds should ideally be 10 miles per hour to sustain the swift rotations of the turbines. Each turbine approximately produces about 50 to 300 kilowatts of electricity. A number of turbines powered together is known as a wind farm, which generates bulk electrical power. Wind energy from wind turbines can be produced for stand-alone applications or can be produced centrally for distribution to electric grids, like conventional power plants (Brosius n.d.).
Windmills served different purposes and are continually being modified with time. Windmills built to harness wind energy need large amounts of turbines to provide a reasonable amount of power. Today, the improvement of the turbine technology intends to turn the motion of turbine blades into effective energy source. In some cases, turbines do explode (Lenkefi 2005). One flaw of wind farms is the aesthetic degradation of the farms locations. Ideally, windmills should be built in very windy areas (i.e. near-shore). The breathtaking scenery and vibe of the beach or shoreline may be disfigured because of the towering windmills constructed in the area. Likewise, residents near wind farms complain about the unbearable noise windmills produce on windy days and even not-so-windy days. With regards to the noise disturbance, conservation orders protect areas of open countryside which prevents the construction of a wind farm in the particular area. In the occasion that there is no conservation, residents protest eagerly to stop the turbines being built. The only viable option left is to use offshore wind farms (Lenkefi 2005).
Generic windmills unpleasant whirling noise resulted to the continual modifications of the machinery.
According to Alternative Energy Sources, an Ontario-based company created the Magenn Power Air Rotor System (MARS). MARS is a helium filled, cylindrical device, deployed at 1000ft maximum altitude. It rotates about its horizontal axis in response to the wind, whereas electricity is generated by rotation of the MARS unit, and is consequently transferred by cables to the ground into a transformer. MARS unit is filled with helium that provides the lift to keep it suspended in the air, with the provided by the rotation of the object in air, known as the Magnus Effect.
Wind energy can be converted into mechanical energy. In 2006, a total of 73,904 MW was generated. The figure shows how much wind energy is currently harvested by the entire world and a future prediction.
Apparently, the ultimate source of energy on Earth is the sun. The heat and light it radiates are essential to support life on earth, and fortunately for mankind, the sun never ceases to shine every morning. Solar energy is the energy received by the earth from the sun, in the form of solar radiation, which makes the production of solar electricity possible (Solar Energy Definition).
As technology become more advance nowadays, people are able to maximize and explore the received from the sun. From simple solar cells used to power calculators and watches, it evolved to large solar panels mounted on roofs or designated plants to provide electricity to a household or large electric applications, respectively (Solar Energy Definition). Solar cells are made of semiconducting materials designated to convert sunlight directly into electricity. Upon absorption of sunlight, the heat knocks electrons loose from their atoms, and electrons motion in the material produces electricity. The conversion of light (photons) to electricity (voltage) is called the photovoltaic (PV) effect. About 40 cells are combined to produce a module, where they are arranged in PV arrays at a fixed angle to capture the most sunlight over the course of a day. A typical commercial solar cell has an efficiency of 15 (about one-sixth of the sunlight which strikes the cell) in generating electricity. The first solar cells built in the 1950s even had efficiencies of less than 4. The current goal is to improve solar cell efficiencies while minimizing the cost per cell (Photovoltaic Systems).
Today, the solar panels have very high prices in the market. But upon installation, and weighing its long-term thrift benefits, cost could be very worthy. In the UK, The Green Project, formerly the Heat Project, was created and has provided insulation measures and solar systems to UK properties for 14 years. This project drove down energy bills in households and also made them more energy efficient (The Green Project).
Aside from the huge cost of installation of solar panels, which proves to be the major setback of solar energy, solar panels additionally require a large area for installation to achieve a good level of efficiency. Likewise, the absorption of light depends on many factors, such as the direction of the suns rays, the presence of clouds, andor the pollution in the air. Added to that, no solar energy can be produced during nighttime, although a battery backup system may be used. On a positive note, one of the major advantages upon correct installation is the long-term savings in electricity bills. After the initial investment is recovered, electricity will be free. Added to that, solar energy systems have no recurring costs, are virtually maintenance-free and can last for decades. Likewise, a household powered by solar panels will not be affected by power outages. Also, Solar Energy does not pollute the air by releasing carbon dioxide, nitrogen oxide, sulphur dioxide or mercury into the atmosphere and it will reduce dependency on centralized traditional forms of electrical generation (Solar Energy Advantages Disadvantages.).
Either Wind or Solar Energy is often regarded as the most worlds most widely-used renewable energy. But at least in the US, Biomass has been the most highly produced alternative energy since 2000 (Lenkefi). Biomass supplies almost 15 times as much energy as wind and solar power combined in the US (How Biomass Energy Work).
Biomass energy is derived from a wide variety of resources, such as tree and grass crops, forestry, agricultural, and urban wastes. The conventional and most common way to capture the energy from biomass is to burn the resources, consequently make heat, steam, andor electricity indirectly (How Biomass Energy Work).
A major setback is that biomass is burned similarly the way fossil fuels are burned. Burning the resources would create the same amount of carbon dioxide. If improperly controlled, this can result to pollution (How Biomass Energy Provides...).
In light with that concern, advances in recent years have shown that there are more efficient and cleaner ways to use biomass. Instead of burning them directly, they can be converted into liquid fuels. They can be cooked in a process called gasification, which aims to produce combustible gases. In addition, biomass can be mixed and burnt with coal in power plant. The process is called co-firing. Biomass feedstock can substitute up to 20 percent of the coal used in a boiler. As a result, the said substitution can lead to reductions of harmful carbon emissions. In addition, lower operational costs and greater energy security can be achieved (How Biomass Energy Work).
Some environmentalists argue that Biomass Energy is not totally green because of the implied burning processes done before the energy is obtained. They are slightly correct, but given the conditions, Biomass significantly decreases the harmful effects as opposed to completely relying on fossil fuels.
Geothermal Energy is another popular form of renewable energy. It harnesses the heat energy present underneath the Earth. Hot rocks underneath the ground heat water which produce steam. The steam that shoots up, form the drilled holes in the ground, is purified and is used to drive turbines, which in turn power electric generators. The dangerous aspect is that when holes are improperly grilled, they can release hazardous minerals and gases. In addition, sites are prone to run out of steam. On the other hand, the advantage of a successful geothermal site location is that it produces no harmful by-products. Likewise, it is generally self-sufficient and has little effect on the natural landscape (Orloff).
Hydroelectric energy refers to the utility of the motion of water to drive turbines. Initially, the water is held in a reservoir or dam, the control gates open, so the water rushes through the penstock which eventually turns the turbine. The turbine spins the generator which generates the electric current. The electricity goes to the transformer in the powerhouse and is transformed into a usable form, after which it travels through the power lines and is distributed to households or businesses.
Ideally, hydroelectric energy is efficient when it comes to electricity generation. In addition, the process is non-polluting and it prevents floods. Though, the construction of hydroelectric dams can harm many fishes and species that live on the area and destroy the land around the dam (Hydroelectric Energy).
Nuclear energy is perhaps the most highly-controversial and debated form of renewable energy. It can be produced in two different ways either by large nuclei split (nuclear fission), or small nuclei are combination (nuclear fusion), both to release energy (Nuclear Energy).
The construction of nuclear power plants has raised many political and environmental concerns. People fear that the energy might be used for the wrong reasons, like for war or terrorism. Nuclear weapons were proven to be very deadly during the war. In addition, the risk of a meltdown is very frightful. It can emit harmful radiation and can cause huge explosions. Amidst these potential hazards, the risk of building nuclear power plants is said to be overblown by the government, media, and the public. With the huge dependency of the nations in fossil fuels today, energy resources such as coal and oil are rapidly reaching depletion, and their best replacement is nuclear energy (Nuclear Politics).
Indeed, each renewable forms of energy have its own major benefit and downfall. But what is clear is that when done properly, they provide less harm as compared to the use of fossil fuels in the present. Likewise, renewable energy serves as the best solutions when fossil fuels and other non-renewable resources have reached depletion.
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