Critical Analysis of the viability of Renewable Energy

INTRODUCTION AND OVERVIEW
This Essay would tend to analyse and define Renewable Energy as a whole.It would also list and discuss types/main forms of renewable energy and its commercialization to members of the public.
The essay would aim to discuss economic importance of Renewable energy,new and future use of renewable energy as regards research and methods.

Finalise and suggest for safe use of renewable energy.
DEFINITION OF RENEWABLE ENERGY
Renewable energy could be defined as energy which is extracted from natural resources such as,sunlight,wind,rains,geothermal heat and tides which in turn are renewable over and over.
TYPES/MAIN FORMS OF RENEWABLE ENERGY
i.Wind Power

One hot type of alternative energy is wind power which is steadily growing at the rate of 30% annually, with a worldwide installed capacity of 121,000 megawatts (MW) in 2008, and is widely used in European countries and the United States. While some people may feel these are hideous looking intruders, wind energy could generate 20 percent of the electricity needed by households and businesses in the eastern half of the United States by 2024.
ii.Hydropower

Brazil has one of the largest renewable energy programs in the world, involving production of ethanol fuel from sugar cane, and ethanol now provides 18% of the country’s automotive fuel. They have also recently been granted permission for building a huge dam in the heart of the Amazon rainforest which would generate a ton of hydroelectric power helping with Latin America’s demand for electricity. Unfortunately, this form of renewable energy may hurt the local indigenous people and have a negative impact on the environment.
iii. Solar Energy

In searching for a definition of renewable energy, you are bound to come across solar power which use photovoltaic cells to convert the radiation from the sun into usable energy. These extremely versatile systems can power everything from your small PUMA cell phone to massive building complexes. In fact, after Haiti’s horrendous and disastrous earthquake, solar cells easily replaced a dwindling diesel supply. Alan Doyle, a science editor at MSNBC, recently wrote that a single solar water purification system, recovered from the rubble by the Red Cross, is now purifying 30,000 gallons (over 110,000 liters) of water a day.
iv.Biomass
Biomass (plant material) is a renewable energy source because the energy it contains comes from the sun. Through the process of photosynthesis, plants capture the sun’s energy. When the plants are burnt, they release the sun’s energy they contain. In this way, biomass functions as a sort of natural battery for storing solar energy. As long as biomass is produced sustainably, with only as much used as is grown, the battery will last indefinitely.
In general there are two main approaches to using plants for energy production: growing plants specifically for energy use, and using the residues from plants that are used for other things. The best approaches vary from region to region according to climate, soils and geography.[
v.Biofuel
Brazil has bioethanol made from sugarcane available throughout the country. Shown a typical Petrobras gas station at Sao Paulo with dual fuel service, marked A for alcohol (ethanol) and G for gasoline.Biofuels include a wide range of fuels which are derived from biomass. The term covers solid biomass, liquid fuels and various biogases. Liquid biofuels include bio alcohols, such as bioethanol, and oils, such as biodiesel. Gaseous biofuels include biogas, landfill gas and synthetic gas.
Bioethanol is an alcohol made by fermenting the sugar components of plant materials and it is made mostly from sugar and starch crops. With advanced technology being developed, cellulosic biomass, such as trees and grasses, are also used as feed stocks for ethanol production. Ethanol can be used as a fuel for vehicles in its pure form, but it is usually used as a gasoline additive to increase octane and improve vehicle emissions. Bioethanol is widely used in the USA and in Brazil.
Biodiesel is made from vegetable oils, animal fats or recycled greases. Biodiesel can be used as a fuel for vehicles in its pure form, but it is usually used as a diesel additive to reduce levels of particulates, carbon monoxide, and hydrocarbons from diesel-powered vehicles. Biodiesel is produced from oils or fats using trans esterification and is the most common biofuel in Europe.
Biofuels provided 2.7% of the world’s transport fuel in 2010.
vi.Geothermal energy.
Krafla Geothermal Station in northeast IcelandGeothermal energy is energy obtained by tapping the heat of the earth itself, both from kilometers deep into the Earth’s crust in volcanically active locations of the globe or from shallow depths, as in geothermal heat pumps in most locations of the planet. It is expensive to build a power station but operating costs are low resulting in low energy costs for suitable sites. Ultimately, this energy derives from heat in the Earth’s core.
Three types of power plants are used to generate power from geothermal energy: dry steam, flash, and binary. Dry steam plants take steam out of fractures in the ground and use it to directly drive a turbine that spins a generator. Flash plants take hot water, usually at temperatures over 200 °C, out of the ground, and allows it to boil as it rises to the surface then separates the steam phase in steam/water separators and then runs the steam through a turbine. In binary plants, the hot water flows through heat exchangers, boiling an organic fluid that spins the turbine. The condensed steam and remaining geothermal fluid from all three types of plants are injected back into the hot rock to pick up more heat.[citation needed]
The geothermal energy from the core of the Earth is closer to the surface in some areas than in others. Where hot underground steam or water can be tapped and brought to the surface it may be used to generate electricity. Such geothermal power sources exist in certain geologically unstable parts of the world such as Chile, Iceland, New Zealand, United States, the Philippines and Italy. The two most prominent areas for this in the United States are in the Yellowstone basin and in northern California. Iceland produced 170 MW geothermal power and heated 86% of all houses in the year 2000 through geothermal energy. Some 8000 MW of capacity is operational in total.
ECONOMIC IMPORTANCE OF RENEWABLE ENERGY
Renewable energy is often considered as the best way to tackle global warming and climate change. The more renewable energy we use the less fossil fuel we burn, and less burning of fossil fuels means less carbon dioxide emissions and lesser impact to climate change.
There are really plenty of reasons to choose renewable energy over fossil fuels but we must not forget that renewable energy is still not ready to completely replace fossil fuels.
Some day it will be but not just yet. The most important thing to do right now is to further develop different renewable energy technologies in order to ensure that once this day comes world wouldn’t have to worry whether renewable energy will be able to deliver the goods or not.
Together with costs renewable energy will also need to improve its efficiency. For instance, average solar panels have efficiency of around 15% which means that lot of energy gets wasted and transferred into heat, instead of some other form of usable energy. However, there are many ongoing researches with the goal to improve efficiency of renewable energy technologies, some of which have been really promising, though we are yet to see some highly efficient and commercially viable renewable energy solution.
Renewable energy sector could decide to choose a “sit and wait strategy” because fossil fuels will eventually become depleted and renewable energy would then remain as the best alternative to satisfy world’s hunger for energy. But this would be a bad strategy for two reasons: energy security and climate change
Renewable energy is very popular topic these days and here are some advantages and disadvantages of renewable energy.
Like fossil fuels do so does renewable energy have certain advantages and disadvantages. Economy, ecology, and efficiency are only some of the factors through which we should look renewable energy when discussing its advantages and disadvantages.
As the name already suggests renewable energy sources cannot be depleted like this is the case with fossil fuels. Fossil fuels are limited, and therefore one day coal, oil, and natural gas will be depleted but the same scenario won’t happen with renewable energy sources because Sun will continue to shine, wind will continue to blow, etc. It is difficult to say how long will fossil fuels still be able to satisfy large part of global energy demand, some energy experts believe this is likely to last till the end of this century, but in any case once fossil fuels become depleted world will need to have already established alternative in form of renewable energy.
From the ecological point of view renewable energy has extreme advantage over fossil fuels, renewable energy sources are clean energy sources and unlike coal, oil, and natural gas release none or negligible carbon emissions. Fossil fuels on the other hand when burning release harmful carbon emissions that not only pollute our planet but have contributed to the severity of climate change impact.
The cost-competitiveness of renewable energy sources, despite the serious improvement in renewable energy technologies in the last couple of years still remains one of the biggest disadvantages of renewable energy. In order for renewable energy to become cost-competitive with fossil fuels lot more research will be needed to mostly improve efficiency of renewable energy technologies because efficiency and economy still outweigh positive environmental effects in eyes of many people.
Renewable energy also needs to work on energy storage solutions to ensure reliability of delivery because the most important renewable energy sources are intermittent (wind, solar), and are therefore not totally reliable.
The lack of tradition is also one disadvantage of renewable energy. Fossil fuels have long tradition, and many renewable energy sectors have just started developing. Tradition that fossil fuels have on their side has contributed to the development of powerful fossil fuel lobbies that have significant impact on politics, and these lobbies use this influence to get important decisions their way.
Many countries in the world rely on foreign oil import, and by developing their own domestic renewable energy sectors they would help decrease the dependence on importing oil from other countries, and would also diversify their own energy portfolio in the process.
The development of renewable energy sectors can also create many economic benefits for countries, mostly in form of many new green jobs.
CONCLUSION
. Source: REN21[16]
BIBLOGRAPHY
renewable energy.” Encyclop?dia Britannica. Encyclop?dia Britannica Online. Encyclop?dia Britannica, 2011. Web. 31 Jul. 2011. .