Advantages And Disadvantages Of Renewable Energy Environmental Sciences Essay

This work will represent opinions and thoughts of different scientists, sociologists and politics related to the most discussing topic now days, renewable sources of energy. Let’s go back in time hundred thousand years ago when our yet not developed ancestors noticed that fire can be used in many purposes. It was the first energy source. Fossil fuels are the main representative of non-renewable energy group and wind, water, solar power is renewable group, because they are unlimited and can be easily recycled. Major concern in the world is that fossil fuel usage produce dramatically huge emission. President of the United States claimed in his speech to United Nations that “We’re investing billions to capture carbon pollution so that we can clean up our coal plants”(President Obama, 2010). Many debates have occurred since people started to think about future and became threatened that fossil fuels can just go out of stock one day, more over such things as wind miles, solar power panels were represented to the world, so the solution is already exist for problem of pollution and destroying environment due to the incredible industrial consumption of energy. However economical question has arisen. This type of technologies is very expensive now, but on other hand the price on them would never be reduced without using it. At present days it is possible to see how this usage of these technologies started to accelerate. Many people and different companies started to apply green energy technologies in their life. For example here in Dubai 80% of the water heated ether by natural sun light, heating the tank on the roof or again by the power of sun light but now, recycled in to the pure electric energy using solar power panels installed on the top of the roof. Consequence of this is that emission made to the air is reduced, in addition once this panel is installed company or person can save money because it has its own resource of hot water. However there is a bad side of any good. Wind mile is dependent on wind and solar power is dependent on sun. Yet it is decidable question which can easily be solved by accumulating energy in battery packs in case of emergency, or transferring energy from sunny and windy regions to others. How sad president of Russia Medvedev: “The environment and the economy do not contradict each other. A properly functioning economy is an environmentally friendly economy.” (President Medvedev, 2010)

WIND POWER

The most important characteristic that determines the energy value of wind it is – speed. Due to a number of meteorological factors (disturbance of the atmosphere, changes in solar activity, the amount of heat energy reaching the Earth, and other causes) and also due to the influence of relief conditions continuous duration of the wind in the area, its speed and direction vary randomly. Therefore, the power that can produce wind-setting at different times, one can predict with a very low probability. At the same time, the total production of the unit, especially over a long period of time can be calculated with high accuracy, since the average wind speed and frequency of the velocity distribution within a year or season change little.

Airflow, as well as any moving body, has the energy of motion, or the reserve of kinetic energy. The latter with wind turbine or other working body is transformed into mechanical energy. Depending on the purpose of wind turbine mechanical energy by means of actuators (generators, compressors, electrolytic, etc.) can be converted into electricity, heat or mechanical energy, as well as the energy of compressed air.

The principle of wind power is simple: the wind turns the blades of a windmill, driving the shaft generator. The generator in turn produces electrical energy. It turns out that wind power work, how toy cars on batteries, only the principle of their action is opposite. Instead of converting electrical energy into mechanical energy, wind energy is converted into electrical current.

SOLAR POWER

Solar energy – the use of sunlight to generate energy in any form. Solar power uses a renewable source of energy and the potential to become environmentally friendly that is not generating hazardous waste.

The advantages of using solar energy:

1) Accessibility and inexhaustible source (the sun).

2) Theoretically, the complete security to the environment (but currently in production of solar cells and in themselves harmful substances are used).

Now solar energy is widely used in cases where the inaccessibility of other energy sources combined with an abundance of solar radiation justifies its cost.

Sun. Source of life and hard killer, giving the chance to be born and grow up every living organism on Earth for several billion years. Seriously about technology “taming” of sunlight people began to think only in the last century.

Currently, solar power plants are built mainly of two types: Solar power tower and solar power distributed (modular) type.

In the solar power tower central receiver used with a field of heliostats, provides a degree of concentration in a few thousand. System for tracking the sun is much more complicated since it requires rotation around two axes. The system is controlled by the computer. As a working body in the heat engine is commonly used steam temperatures up to 550 ° C, air and other gases – up to 1000 ° C, low-boiling organic liquids (including freon) – up to 100 ° C, liquid metal coolant – up to 800 ° C.

DISADVANTAGES OF RENEWABLE ENERGY

Solar power: Because of the relatively small magnitude of solar constant for solar energy requires the use of large areas of land for power plants (for example, 1-GW power plants it could be several tens of square kilometers). However, this drawback is not so great (for example, hydropower output from the use of much larger tracts of land). In addition, photovoltaic cells on the large solar power plants installed at a height of 1,8-2,5 m, which allows the use of land for power plants for agricultural purposes, such as for grazing.

The problem of finding large areas of land for solar power is solved in the case of the solar balloon stations, suitable for both terrestrial and maritime and for high-rise home.

The flow of solar energy on Earth’s surface is strongly dependent on latitude and climate. In various places the average number of sunny days per year can vary greatly.

Technical problems:

1) Solar power does not work at night and not effectively work in the morning and evening twilight. The peak power consumption falls on the evening. In addition, power plants can dramatically and unexpectedly fluctuate because of changing weather.

2) The high cost of solar cells. Probably with the development of technology will overcome this shortcoming. In 1990-2005 prices for solar cells decreased on average by 4% a year.

3) Lack of efficiency of solar cells.

4) The surface of the graphic panels should be cleaned from dust and other contaminants. With their area of ​​several square kilometers of it can cause difficulties.

5) The efficiency of photovoltaic cells decreases significantly when heated, so there is a need to install cooling systems, usually water.

6) After 30 years of operation, the efficiency of photovoltaic cells begins to decline.

Wind power:

Wind energy plants produce two types of noise:

Mechanical noise – noise from the operation of mechanical and electrical components (for modern wind power is virtually absent, but is significant in the older models of wind turbines)

Aerodynamic noise – the noise from the interaction of wind flow with the blades installed (amplified during the passage of blades past the tower of wind turbines)

In the vicinity of wind turbines in the axis of wind turbine noise level are sufficiently large wind turbines can exceed 100 dB.

An example of such design errors is a wind turbine Grovian. Because of the high noise level setting worked about 100 hours and was dismantled.

Laws adopted in the UK, Germany, the Netherlands and Denmark, restrict the noise level of running wind power plant of up to 45 dB in daytime and 35 dB at night. Minimum distance from installation to homes – 300 m.

Low frequency vibrations transmitted through the soil, causing significant jitter windows in homes at a distance of 60 m from the megawatt-class wind turbines.

Population of bats living near the wind farm on the order of magnitude more vulnerable than the population of birds. Near the ends of turbine blades, a region of reduced pressure, and a mammal which has got into it, gets barotraumas. Over 90% of the bats found near wind turbines find signs of internal hemorrhaging. According to the explanation of scientists, the birds have a different structure of the lungs, and therefore more resistant to sudden changes in pressure and suffer only from a direct collision with the blades of wind turbines.

In contrast to conventional thermal power plants, wind farms do not use water that can significantly reduce pressure on water resources.

Metallic structures wind turbines, especially items in the lobes, can cause significant interference to radio reception. The larger the wind turbine, the more noise it can create. In some cases, to solve the problem have to install additional repeaters.

CONCLUSION

Undeniable role of energy in maintaining and further follows the development of civilization. In modern society it is difficult to find at least one area of ​​human activity sequence, which is not required to – directly or indirectly tively – more energy than it can give a human muscles.

During the existence of our civilization many times a change of traditional energy sources for new, more sophisticated. And not because the old source was exhausted.

The sun shone and warmed man always: and yet once people have tamed the fire began to burn wood. Then the wood has given way to the stone coal. Timber resources seemed limitless, but steam engines required more nutritious “food.”

But this was just a stage. Coal will soon yield its leadership in energy markets petroleum.

And here is a new milestone in our days leading fuels are still oil and gas. But for every new cubic meters of gas or a ton of oil to go farther north or east, dig deeper into the ground. It is no wonder that oil and gas will be from year to year cost us all more expensive.

In pursuit of an excess of energy a person deeper into elemental world of natural phenomena and to some pores are not really thought about the consequences of their deeds and acts.

But times have changed. Now new significant step the earth’s energy. There was energy, “gentle.” Constructed so that people do not cut down the branch on which it sits. Concerned about the protection of already heavily damaged biosphere.

Undoubtedly, in future, in parallel with a line of intensive energy development will have extensive rights of citizenship and an extensive line of: non-point sources of energy are not too much power, but with high efficiency, environmentally friendly, easy to handle.

Energy accumulates very quickly, assimilates and incorporates all the newest ideas, inventions and scientific achievements. This is understandable: energy is associated with literally everything, and all drawn to power, depends on it.

Labyrinths of power. Mysterious passages, narrow, winding trail. Full of puzzles, obstacles, unexpected insights, wailing grief and losses, joys and triumphs of clicks. Thorny, is not easy, continuous energy path of humanity. But we believe that we are on the way to an era of energy abundance, and that all the hurdles, obstacles and difficulties will be overcome.

The story of energy may be infinite, innumerable alternative forms of its use, provided that we have to develop that are effective and economical methods. Not so important, what is your opinion about the needs of energy, sources of energy, its quality, and cost? We probably should just accept the fact that the scientist said the sage, whose name remains unknown: “There are no simple solutions, only intelligent choices.”