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Sabtu, 11 Juni 2011

Renewable Energy Stocks

The key to our global energy necessities in the time to come is Renewable Energy. Nowadays we are loosing our supply of uranium and fossil fuels. Not only we are running out of these energy stocks but the costs rises constantly for economic or political reasons. The prices of renewable energy stocks can turn much more competitive. Utilizing the latest technologies, most ocean energy is not cost-effective likened to other renewable energy stocks still the ocean persists as one of the big potential energy reservoir for the time to come. Renewable and non-renewable energy reservoirs are both applied to generate electrical energy, power vehicles, and provide heating, cooling, and light.

Numerous people don't know how renewable energy is made but in point of fact it's not that difficult to understand. Renewable Energy is energy which established from resources that are regenerative or renewable. This means that they cannot be depleted. These resources are healthy for our surroundings and create energy without the bad smuttiness and emissions tied in with fossil-fuels.

While this industry spreads out, the expertness of these support industries is being exploited to allow the support and infrastructure required for the progress of renewable energy production globally. Multinational companies are looking for green or renewable resource technologies and companies to invest in, fund, acquire, license or strategically partner with. This is the cause for the giant growth. Renewable energy systems embrace a enormous, several array of technologies, and the present-day status of these can vary considerably. Some technologies are already developed and economically competitive.

All over the world we recognize that utilizing inexhaustible resources has the potential to supply us with fresher air, a more diverse energy portfolio, and less dependence on foreign fossil fuels. Presently renewable resources scores for just 3.4 percent of total global power generation. The International Energy Agency recently published a news report forecasting that in order to cut down greenhouse gasemissions 50% by 2050, global investment funds in renewable energy, energy efficiency and carbon sequestration will need to reach roughly US $45 trillion dollars by that date.

They are bearing that 60% of all our energy will come from renewable resources by the year 2070. But the sooner we stick with the attitude that today is better than tomorrow, the bigger the chance to increase this figure to 80%. 

Renewable energy is sustainable energy that comes from the natural surroundings. Renewable energy or also known as Green Power, is power that comes from renewable resources such as the sunlight, wind, hydro-electric dams and organic matter (biomass). These resources are incessantly replenished by nature and are a healthier source of energy.

If you want to know more about renewable energy, take a look at Renewable Energy Stocks.
Visit Renewable Fuels Stocks and Ethanol Blends also to get familiar with renewable energy.

Read more: http://www.articlesbase.com/environment-articles/renewable-energy-stocks-949879.html#ixzz1OyW9BRYo 
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Renewable energy: The good, the bad, and the so-so

The green movement has created a plethora of buzzwords. One of the more popular phrases is renewable energy. And for good reason. Businesses, traditional and emerging, will soon be affected by how they will respond to the reality of renewable energy depending on where they fall in the supply chain. 

Renewable energy is a term that refers to those potential sources of energy that are naturally replenished, which means that using them does not decrease the amount available in the future. This contrasts with nonrenewable sources (fossil-based fuels) that have a limited supply and will eventually be used up. Renewable energy sources include sunlight, hydrosphere/water cycle, geothermal and some types of biomass and biofuels. Think of energy as a source and electricity as an application. The mechanisms used to generate electricity from these sources vary considerably. For sunlight, there are photovoltaic technologies that generate electricity directly from sunlight. But there are also systems that use the sunlight to heat an intermediate fluid, which is used to turn turbines to generate electricity. There are multiple ways that water can be used to provide electricity, of which the most commonly used is the hydroelectric dam. Other systems that produce electricity from water include wave power systems that convert the kinetic energy of waves into electricity, tidal power systems that use the kinetic energy of tidal flows in a similar fashion, and systems that take advantage of the temperature differences between surface waters and deeper waters in the ocean to generate electricity. Geothermal systems rely on the heat of the earth's interior to generate electricity in various ways, depending on the specific nature of the site. Biomass and biofuels consist of fuels derived from plant and other organic matter, which are renewable depending on the sustainability of the agricultural practices that provide the biomass. Examples include ethanol and biodiesel liquid fuels for transportation, and solid biomass from unused portions of other crops for electricity generation. Presently, renewable energy sources provide only a small fraction of global energy production, and the majority of this is from biomass burning such a wood (which while renewable in the strictest sense is not environmentally friendly) in undeveloped regions of the world. Renewable energy provides less than 1% of the world's energy production even though its use is expected to grow rapidly amid risingconcerns about global warming and the rising price of oil. The biggest impediment to the widespread use of renewable energy sources in the past has been its price compared to the price of coal, natural gas, and petroleum. At present, wind energy costs $0.04-$0.08 per kWh, while coal costs $0.04 per kWh. Other renewable energy sources are even more expensive, such as solar thermal at $0.12-$0.34 per kWh and solar photovoltaic at $0.25-$1.60 per kWh. Water sources vary in cost from being cheaper than coal to costing three times as much. This cost differential, however, is narrowing as the price of oil rises and new technological innovations are bringing down the prices of renewables. Looking forward, the increasing likelihood of carbon taxes or emissions trading schemes being implemented in much of the developed world means that the cost of generating electricity from coal, natural gas, and petroleum will rise even more precipitously, which will make renewable energy even more attractive for future development. The future of renewable energy depends on how government energy policy will develop over the course of the next presidential administration and congress. Will carbon taxes or emissions trading schemes be enacted to limit greenhouse gas emissions? Will green grid technologies become widespread? Will the development of new oil supplies be allowed? All of these possible scenarios will affect the future deployment of renewable energy technologies.As an example, consider the application of rooftop solar photovoltaic systems. Not only will these systems provide electricity to homes and businesses, but they can even be used to sell energy back to the power utility. Farmers and ranchers can plant wind turbines on land unsuitable for growing crops. The widespread use of smart grid technologies can become a major method of decentralizing power generation. Similarly, if emissions trading schemes are enacted, then the rising cost of carbon-producing energy sources will force a shift to renewable energy technologies for large portions of our energy needs. This is deemed so likely that many believe that renewable energy technologies will be the next major industrial boom, similar to the computer technology revolution of the 1980s and the internet revolution of the late 1990s. Increasingly, large quantities of venture capital are pouring into renewable energy companies in expectation of just such an outcome. How you position your firm to take advantage of the probable boom in renewable energy depends on your business's energy needs and usage. If green grid technology becomes widespread, the opportunity presents itself to businesses to become both an electricity consumer and a supplier. If carbon taxes or emissions trading systems drive the move away from petroleum transport fuels to biomass transport fuels, it is important to be prepared for that as well. As the renewable energy debate gains momentum, NOW is the time to prepare for its eventual inevitability to help protect your business from rising energy and transportation costs.Read more: http://www.articlesbase.com/regulatory-compliance-articles/renewable-energy-the-good-the-bad-and-the-soso-498382.html#ixzz1OyTSK1wF Under Creative Commons License: Attribution

Making use of renewable energy

Most of our energy sources are from petroleum, natural gas and coal. Nuclear electric power and renewable sources are the least used for power consumption. The five renewable energy or alternative energy sources that are commonly used include water or hydropower, geothermal, solar, wind and biomass. Biomass includes wood, municipal solid waste, landfill gas, biogas, ethanol and biodiesel. Before, people rely in the use of renewable energy mostly wood. Wood is used to provide heat and light. But when fossil fuel was produced like petroleum and coal, renewable energy was set aside. 

However, nowadays, since fossil fuels emit greenhouse effect which can damage our mother earth, we are again trying to find ways to make use of renewables. Since renewable energy is ecological and can be replenished, it is the best alternative energy available. Waste to Energy is an example of renewable source which is really a promising source of energy. Unlike other renewable resources, the waste to energy source does not use natural resources instead waste materials. Aside from the energy production, it significantly helps in eliminating waste materials thus helping save our environment.

If nations will focus more on developing renewable sources such as waste to energy systems, then we can eventually decrease our dependence on fossil fuels. Moreover, there are studies being conducted with the use of methane as a source of energy. Rotting garbage emits methane thus it is part of biomass-type of renewable energy. If we will be able to use electricity coming from garbage, we won't just be making use of renewable energy but we can also decrease waste in the world. 

Renewables also provide heat and steam for industrial purposes. These are used for transportation and heat for homes. For this purpose, ethanol is the most commonly used renewable energy. Even if in time, we will be using renewable fuels as a source of our energy consumption. Good thing the advancements in science nowadays are of great help in maximizing the use of renewables just like what the Biosphere Technology does. This technology is a waste to energy system that helps in green energy production and waste management without polluting our environment. 

Biosphere technology uses gasification process wherein it employs thermal conversion of waste materials to produce green energy and other end products like pozzolana, distilled water, high alloy steel wire and carbon black. Developing renewable energy such as this significantly helps in environmental conservation. One way of helping our environment is to promote the use of renewable energy source like biosphere technology.

Read more: http://www.articlesbase.com/environment-articles/making-use-of-renewable-energy-4838598.html#ixzz1OySEbcLo 
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Renewable energy



Renewable energy is energy generated from natural resources—such as sunlight, wind, rain, tides, and geothermal heat—which are renewable (naturally replenished). In 2006, about 18% of global final energy consumption came from renewables, with 13% coming from traditional biomass, such as wood-burning. Hydroelectricity was the next largest renewable source, providing 3% of global energy consumption and 15% of global electricity generation.
Wind power is growing at the rate of 30 percent annually, with a worldwide installed capacity of 121,000 megawatts (MW) in 2008, and is widely used in European countries and the United States. The annual manufacturing output of the photovoltaics industry reached 6,900 MW in 2008, and photovoltaic (PV) power stations are popular in Germany and Spain. Solar thermal power stations operate in the USA and Spain, and the largest of these is the 354 MW SEGS power plant in the Mojave Desert. The world's largest geothermal power installation is The Geysers in California, with a rated capacity of 750 MW. 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 percent of the country's automotive fuel. Ethanol fuel is also widely available in the USA.
While most renewable energy projects and production is large-scale, renewable technologies are also suited to small off-grid applications, sometimes in rural and remote areas, where energy is often crucial in human development. Kenya has the world's highest household solar ownership rate with roughly 30,000 small (20–100 watt) solar power systems sold per year.
Some renewable-energy technologies are criticized for being intermittent or unsightly, yet the renewable-energy market continues to grow. Climate-change concerns, coupled with high oil prices, peak oil, and increasing government support, are driving increasing renewable-energy legislation, incentives and commercialization. New government spending, regulation and policies should help the industry weather the 2009 economic crisis better than many other sectors.

Main forms/sources of renewable energy

The majority of renewable energy technologies are powered by the sun. The Earth-Atmosphere system is in equilibrium such that heat radiation into space is equal to incoming solar radiation, the resulting level of energy within the Earth-Atmosphere system can roughly be described as the Earth's "climate." The hydrosphere (water) absorbs a major fraction of the incoming radiation. Most radiation is absorbed at low latitudes around the equator, but this energy is dissipated around the globe in the form of winds and ocean currents. Wave motion may play a role in the process of transferring mechanical energy between the atmosphere and the ocean through wind stress. Solar energy is also responsible for the distribution of precipitation which is tapped by hydroelectric projects, and for the growth of plants used to create biofuels.
Renewable energy flows involve natural phenomena such as sunlight, wind, tides and geothermal heat, as the International Energy Agency explains:
Renewable energy is derived from natural processes that are replenished constantly. In its various forms, it derives directly from the sun, or from heat generated deep within the earth. Included in the definition is electricity and heat generated from solar, wind, ocean, hydropower, biomass, geothermal resources, and biofuels and hydrogen derived from renewable resources.
Each of these sources has unique characteristics which influence how and where they are used.

Wind power


Vestas V80 wind turbines
Airflows can be used to run wind turbines. Modern wind turbines range from around 600 kW to 5 MW of rated power, although turbines with rated output of 1.5–3 MW have become the most common for commercial use; the power output of a turbine is a function of the cube of the wind speed, so as wind speed increases, power output increases dramatically. Areas where winds are stronger and more constant, such as offshore and high altitude sites, are preferred locations for wind farms. Typical capacity factors are 20-40%, with values at the upper end of the range in particularly favourable sites.
Globally, the long-term technical potential of wind energy is believed to be five times total current global energy production, or 40 times current electricity demand. This could require large amounts of land to be used for wind turbines, particularly in areas of higher wind resources. Offshore resources experience mean wind speeds of ~90% greater than that of land, so offshore resources could contribute substantially more energy. This number could also increase with higher altitude ground-based or airborne wind turbines.
Wind power is renewable and produces no greenhouse gases during operation, such as carbon dioxide and methane.

Water power

Energy in water (in the form of kinetic energy, temperature differences or salinity gradients) can be harnessed and used. Since water is about 800 times denser than air, even a slow flowing stream of water, or moderate sea swell, can yield considerable amounts of energy.

One of 3 Pelamis P-750 Ocean Wave Power machines in the harbor of Peniche, Portugal
There are many forms of water energy:
  • Hydroelectric energy is a term usually reserved for large-scale hydroelectric dams. Examples are the Grand Coulee Dam in Washington State and the Akosombo Dam in Ghana.
  • Micro hydro systems are hydroelectric power installations that typically produce up to 100 kW of power. They are often used in water rich areas as a Remote Area Power Supply (RAPS). There are many of these installations around the world, including several delivering around 50 kW in the Solomon Islands.
  • Damless hydro systems derive kinetic energy from rivers and oceans without using a dam.
  • Ocean energy describes all the technologies to harness energy from the ocean and the sea:
    • Marine current power. Similar to tidal stream power, uses the kinetic energy of marine currents
    • Ocean thermal energy conversion (OTEC) uses the temperature difference between the warmer surface of the ocean and the colder lower recesses. To this end, it employs a cyclic heat engine. OTEC has not been field-tested on a large scale.
    • Tidal power captures energy from the tides.
    • Wave power uses the energy in waves. Wave power machines usually take the form of floating or neutrally buoyant structures which move relative to one another or to a fixed point.
  • Osmotic power or salinity gradient power, is the energy retrieved from the difference in the salt concentration between seawater and river water. Reverse electrodialysis (PRO) is in the research and testing phase.
  • Vortex power is generated by placing obstacles in rivers in order to cause the formation of vortices which can then be tapped for energy.

Solar energy

 Monocrystalline solar cell
In this context, "solar energy" refers to energy that is collected from sunlight. Solar energy can be applied in many ways, including to:
  • Generate electricity using photovoltaic solar cells.
  • Generate electricity using concentrating solar power.
  • Generate electricity by heating trapped air which rotates turbines in a Solar updraft tower.
  • Generate hydrogen using photoelectrochemical cells.
  • Heat water or air for domestic hot water and space heating needs using solar-thermal panels.
  • Heat buildings, directly, through passive solar building design.
  • Heat foodstuffs, through solar ovens.
  • Solar air conditioning

Biofuel

Plants use photosynthesis to grow and produce biomass. Also known as biomatter, biomass can be used directly as fuel or to produce biofuels. Agriculturally produced biomass fuels, such as biodiesel, ethanol and bagasse (often a by-product of sugar cane cultivation) can be burned in internal combustion engines or boilers. Typically biofuel is burned to release its stored chemical energy. Research into more efficient methods of converting biofuels and other fuels into electricity utilizing fuel cells is an area of very active work.
Liquid biofuel  Information on pump, California.
Liquid biofuel is usually either a bioalcohol such as ethanol fuel or an oil such as biodiesel or straight vegetable oil. Biodiesel can be used in modern diesel vehicles with little or no modification to the engine. It can be made from waste and virgin vegetable and animal oils and fats (lipids). Virgin vegetable oils can be used in modified diesel engines. In fact the diesel engine was originally designed to run on vegetable oil rather than fossil fuel. A major benefit of biodiesel use is the reduction in net CO2 emissions, since all the carbon emitted was recently captured during the growing phase of the biomass. The use of biodiesel also reduces emission of carbon monoxide and other pollutants by 20 to 40%.
In some areas corn, cornstalks, sugarbeets, sugar cane, and switchgrasses are grown specifically to produce ethanol (also known as grain alcohol) a liquid which can be used in internal combustion engines and fuel cells. Ethanol is being phased into the current energy infrastructure. E85 is a fuel composed of 85% ethanol and 15% gasoline that is sold to consumers. Biobutanol is being developed as an alternative to bioethanol.
Another source of biofuel is sweet sorghum. It produces both food and fuel from the same crop. Some studies have shown that the crop is net energy positive ie. it produces more energy than is consumed in its production and utilization.
Solid biomass  Sugar cane residue can be used as a biofuel
Solid biomass is most commonly used directly as a combustible fuel, producing 10-20 MJ/kg of heat. Its forms and sources include wood fuel, the biogenic portion of municipal solid waste, or the unused portion of field crops. Field crops may or may not be grown intentionally as an energy crop, and the remaining plant byproduct used as a fuel. Most types of biomass contain energy. Even cow manure still contains two-thirds of the original energy consumed by the cow. Energy harvesting via a bioreactor is a cost-effective solution to the waste disposal issues faced by the dairy farmer, and can produce enough biogas to run a farm.
With current technology, it is not ideally suited for use as a transportation fuel. Most transportation vehicles require power sources with high power density, such as that provided by internal combustion engines. These engines generally require clean burning fuels, which are generally in liquid form, and to a lesser extent, compressed gaseous phase. Liquids are more portable because they can have a high energy density, and they can be pumped, which makes handling easier.
Non-transportation applications can usually tolerate the low power-density of external combustion engines, that can run directly on less-expensive solid biomass fuel, for combined heat and power. One type of biomass is wood, which has been used for millennia. Two billion people currently cook every day, and heat their homes in the winter by burning biomass, which is a major contributor to man-made climate change global warming. The black soot that is being carried from Asia to polar ice caps is causing them to melt faster in the summer. In the 19th century, wood-fired steam engines were common, contributing significantly to industrial revolution unhealthy air pollution. Coal is a form of biomass that has been compressed over millennia to produce a non-renewable, highly-polluting fossil fuel.
Wood and its byproducts can now be converted through processes such as gasification into biofuels such as woodgas, biogas, methanol or ethanol fuel; although further development may be required to make these methods affordable and practical. Sugar cane residue, wheat chaff, corn cobs and other plant matter can be, and are, burned quite successfully. The net carbon dioxide emissions that are added to the atmosphere by this process are only from the fossil fuel that was consumed to plant, fertilize, harvest and transport the biomass.
Processes to harvest biomass from short-rotation trees like poplars and willows and perennial grasses such as switchgrass, phalaris, and miscanthus, require less frequent cultivation and less nitrogen than do typical annual crops. Pelletizing miscanthus and burning it to generate electricity is being studied and may be economically viable.
Biogas
Biogas can easily be produced from current waste streams, such as paper production, sugar production, sewage, animal waste and so forth. These various waste streams have to be slurried together and allowed to naturally ferment, producing methane gas. This can be done by converting current sewage plants into biogas plants. When a biogas plant has extracted all the methane it can, the remains are sometimes more suitable as fertilizer than the original biomass.
Alternatively biogas can be produced via advanced waste processing systems such as mechanical biological treatment. These systems recover the recyclable elements of household waste and process the biodegradable fraction in anaerobic digesters.
Renewable natural gas is a biogas which has been upgraded to a quality similar to natural gas. By upgrading the quality to that of natural gas, it becomes possible to distribute the gas to the mass market via the existing gas grid.

Geothermal energy

 Krafla Geothermal Station in northeast Iceland
Geothermal energy is energy obtained by tapping the heat of the earth itself, both from kilometers deep into the Earth's crust in some places of the globe or from some meters in geothermal heat pump in all the places 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.
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.
There is also the potential to generate geothermal energy from hot dry rocks. Holes at least 3 km deep are drilled into the earth. Some of these holes pump water into the earth, while other holes pump hot water out. The heat resource consists of hot underground radiogenic granite rocks, which heat up when there is enough sediment between the rock and the earths surface. Several companies in Australia are exploring this technology.


Read more: http://www.articlesbase.com/technology-articles/renewable-energy-1363047.html#ixzz1OyRfIjm5 
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renewable energy source


Across the world energy is being used at an alarmingly higher rate. This is due to rapid industrialization and increased awareness in the consumers. However, all this is taking toll on the fossil fuel reserves as they are depleting fast and their usage becomes expensive. Due to the depletion of non-renewable sources from the earth, people are exploring more ways to employ natural and renewable energy sources. Let us take a close look at the advantages and disadvantages of green energy.
The biggest advantage is that the renewable energy sources are unlimited and they can be used for millions of years. On the other hand the non-renewable sources are limited as they are contained in a reserved quantity below earth’s surface.
There are certain countries which are employing renewable sources to generate electricity. This has brought development and employment has increased. Apart from the economic benefit is great. There can be a boost in the tourism industry if the area which is benefitting from the green energy is continuously getting supplied by electricity.
As natural energy relies on weather condition, it is difficult to predict how much will be generated on a given day. But you can always store the excess energy in the batteries when the weather is favourable, so that you use it when the weather is not suitable.
Did you know that wind power is one of the oldest energy sources? Its conversion was used to propel the boats in ancient times. Presently wind is used mostly to generate electricity and is one of the most potent renewable energy sourcesWind energy will never pollute the environment and will not have any impact on the climatic changes. To add to this, 1 MW wind turbine will save approximately 2,000 tons of carbon dioxide per year. The wind energy is available abundantly and it is 5 times more than the world’s energy consumption.
Yet another advantage of wind and solar energy is that almost anyone can make equipment that will generate electricity using these sources. You can make enough energy to meet the demand of your home. It doesn’t require having a genius mind to make a wind turbine or a solar panel. There is a lot of information provided on the web to guide you to make your own facility. If you have your own wind turbine, you won’t have to worry about the power cuts. The wind power sector and solar power sector are becoming extremely cost effective with numerous researches being done so as to cut the installation cost and enhance the efficiency of the facility.
There are several countries which have wind power farms or solar power farms. They not only generate good amount of electricity, but they are off the grid. As a matter of fact some of them are supplying electricity to their local grids.
You can construct your own wind turbine or a solar panel in less than $200. There are many guides which can help you easily.