How much of the world's energy does the United States use?
In 2009, world total primary energy consumption was 483 Quadrillion Btu. The United States' primary energy consumption was about 95 Quadrillion Btu, about 20% of the world total.
Learn More:
International Energy Statistics: Total Primary Energy Consumption
Last updated: July 9, 2012
Group items tagged
1More
What are the advantages and disadvantages of solar energy - 0 views
-
"Advantages: Solar power gives you a return on your investment, while paying your utility for electricity gives you 0% return. Solar energy is renewable unlike the conventional resources (coal, oil) which will inevitably run out. Non-polluting, no carbon dioxide like fossil fuels Free except for capital expenses. Longevity - solar panels can last over twenty years Low maintenance - solar panels require very little upkeep Independence - an off-grid system allows you to break free from the electrical grid Environmentally friendly because the conversion of energy doesn't produce any carbon dioxide. It comes from the sun, which, unless you are in The South or North pole, comes out almost everyday Solar power is better for the environment, compared to burning fossil fuels and other electrical power. sun is renewable You get clean energy without harming the environment [in term of carbon emissions] , in certain countries, excessive power generated can be sold back to local electricity provider reduces pollution helps create jobs - shores up economy - to build -> you hire - innovate-maintain - basically economic activities reduced dependence on fossil fuels Once installed, the power is free It is environmentally friendly and no pollution is associated with solar power You can sell your excess power back to the power companies It can be installed anywhere You can use batteries to store power for use at night Energy from the sun is renewable, that is, it keeps on coming It is free It does no damage to the earth or its atmosphere It produces no carbon dioxide It doesn't have to be dug up from the ground like coal, oil, natural gas, or uranium It doesn't have to be cut down, like wood from forests. It produces clean, green power in the form of electricity and can be used to power just about everything we need. There is more solar energy landing on the earth every day than it would take to supply the world for a year. Solar energy can heat swimming pools, power calcul
2More
Biofuel Facts - 0 views
-
Much of the gasoline in the United States is blended with a biofuel—ethanol. This is the same stuff as in alcoholic drinks, except that it's made from corn that has been heavily processed. There are various ways of making biofuels, but they generally use chemical reactions, fermentation, and heat to break down the starches, sugars, and other molecules in plants. The leftover products are then refined to produce a fuel that cars can use.
-
On the face of it, biofuels look like a great solution. Cars are a major source of atmospheric carbon dioxide, the main greenhouse gas that causes global warming. But since plants absorb carbon dioxide as they grow, crops grown for biofuels should suck up about as much carbon dioxide as comes out of the tailpipes of cars that burn these fuels. And unlike underground oil reserves, biofuels are a renewable resource since we can always grow more crops to turn into fuel.
8More
HowStuffWorks "How Does Geothermal Compare to Other Energy Sources? " - 0 views
-
Because the energy is generated right near the plant, it saves on processing and transportation costs compared to other types of fuel.
-
The initial costs of geothermal energy are high -- wells can cost $1 to $4 million each to drill, and installation of a home geothermal pump system can run as much as $30,000
-
However, a home geothermal energy pump can cut energy bills by 30 to 40 percent and will pay for itself within 5 to 10 years
- ...3 more annotations...
-
Geothermal energy is considered renewable because the heat is continually replaced. The water that is removed is put right back into the ground after its heat is used.
-
The initial costs of geothermal energy are high -- wells can cost $1 to $4 million each to drill, and installation of a home geothermal pump system can run as much as $30,000 [sources: REPP, Consumer Energy Center]. However, a home geothermal energy pump can cut energy bills by 30 to 40 percent and will pay for itself within 5 to 10 years [source: Consumer Energy Center].
-
about 2,700 megawatts of which is produced in the United States (the equivalent of burning 60 million barrels of oil each year)
-
Not having to pay for transportation can lower the overall cost of geothermal energy. -
Comprehensive up-to-date news coverage, aggregated from sources all over theworld by Google News.Finance - About Google News - Languages and regions - Editors' Pickswww.killdo.de.ggNews Online from Australia and the World ...News headlines from Australia and the world. The latest national, world, business, sport, entertainment and technology news from News Limited news papers.www.killdo.de.ggBreaking News Updates | Latest News Headlines ...Breaking News, Latest News and Current News from FOXNews.com. Breakingnews and video. Latest Current News: U.S., World, Entertainment, Health, ...www.killdo.de.gg
3More
How much CO2 does one solar panel create? | MNN - Mother Nature Network - 2 views
-
solar panels are at least 20x better on the climate than coal, kWh for kWh.
-
Based on that study, solar PV works out to about 50g of CO2 per kWh compared to coal's 975g of CO2 per kWh, or about 20x "cleaner."
2More
How Does Tidal Energy Work - 0 views
-
Tidal turbines use similar technology to wind turbines, although their blades are much shorter and stronger. So a good way to think of them is as underwater windmills. Basically the water currents turn the turbines, which in turn activate a generator that produces electricity. These systems work best where there are very strong tidal zones (Norwegian and British coastlines.) and although it is still in it’s infancy it does show great promise.The upfront cost of these tidal stream systems is very high and also installation and maintenance is difficult.
-
"Tidal turbines use similar technology to wind turbines, although their blades are much shorter and stronger. So a good way to think of them is as underwater windmills. Basically the water currents turn the turbines, which in turn activate a generator that produces electricity. These systems work best where there are very strong tidal zones (Norwegian and British coastlines.) and although it is still in it's infancy it does show great promise. The upfront cost of these tidal stream systems is very high and also installation and maintenance is difficult."
1More
Tidal stream generators - Brightside - 0 views
-
Tidal stream generators look and work like underwater wind turbines. As opposed to using the rising and falling movement of the tides, tidal stream generators take advantage of the fast moving sea currents (tidal streams), which flow when tides are moving in and out. These tidal streams cause the turbines to rotate, turning the generators which generate electricity. Tidal stream generators have the advantage of being much cheaper to build, and do not have as much of an environmental impact as a tidal barrage. The turbines turn relatively slowly, hence do not affect sea life. This is different to tidal barrages which can disrupt fish migrating up rivers from the sea.
2More
EIA Renewable Energy-" Renewable Energy Consumption and Electricity Preliminary 2006 St... - 1 views
-
There is a graphic that shows we don't use much wave energy it's mainly experimental.
11More
Wind Energy Basics - 1 views
-
The major challenge to using wind as a source of power is that it is intermittent and does not always blow when electricity is needed. Wind cannot be stored (although wind-generated electricity can be stored, if batteries are used), and not all winds can be harnessed to meet the timing of electricity demands. Further, good wind sites are often located in remote locations far from areas of electric power demand (such as cities).
-
Although wind power plants have relatively little impact on the environment compared to fossil fuel power plants, there is some concern over the noise produced by the rotor blades, aesthetic (visual) impacts, and birds and bats having been killed (avian/bat mortality) by flying into the rotors. Most of these problems have been resolved or greatly reduced through technological development or by properly siting wind plants.
-
A Renewable Non-Polluting Resource Wind energy is a free, renewable resource, so no matter how much is used today, there will still be the same supply in the future. Wind energy is also a source of clean, non-polluting, electricity. Unlike conventional power plants, wind plants emit no air pollutants or greenhouse gases. According to the U.S. Department of Energy, in 1990, California's wind power plants offset the emission of more than 2.5 billion pounds of carbon dioxide, and 15 million pounds of other pollutants that would have otherwise been produced. It would take a forest of 90 million to 175 million trees to provide the same air quality.
- ...7 more annotations...
-
Cost Issues Even though the cost of wind power has decreased dramatically in the past 10 years, the technology requires a higher initial investment than fossil-fueled generators. Roughly 80% of the cost is the machinery, with the balance being site preparation and installation. If wind generating systems are compared with fossil-fueled systems on a "life-cycle" cost basis (counting fuel and operating expenses for the life of the generator), however, wind costs are much more competitive with other generating technologies because there is no fuel to purchase and minimal operating expenses.
-
-
Wind energy is very abundant in many parts of the United States. Wind resources are characterized by wind-power density classes, ranging from class 1 (the lowest) to class 7 (the highest). Good wind resources (e.g., class 3 and above, which have an average annual wind speed of at least 13 miles per hour) are found in many locations
-
Wind speed is a critical feature of wind resources,
-
In other words, a stronger wind means a lot more power.
-
Horizontal turbine components include: blade or rotor, which converts the energy in the wind to rotational shaft energy; a drive train, usually including a gearbox and a generator; a tower that supports the rotor and drive train; and other equipment, including controls, electrical cables, ground support equipment, and interconnection equipment. Wind turbine diagram - click for enlarged image.
-
Wind is a form of solar energy. Winds are caused by the uneven heating of the atmosphere by the sun, the irregularities of the earth's surface, and rotation of the earth. Wind flow patterns are modified by the earth's terrain, bodies of water, and vegetative cover.
-
How Wind Power Is Generated The terms "wind energy" or "wind power" describe the process by which the wind is used to generate mechanical power or electricity. Wind turbines convert the kinetic energy in the wind into mechanical power.
11More
A Basic Overview of Fuel Cell Technology - 0 views
-
they generate electricity with very little pollution—much of the hydrogen and oxygen used in generating electricity ultimately combine to form a harmless byproduct, namely water.
-
Scientists and inventors have designed many different types and sizes of fuel cells in the search for greater efficiency, and the technical details of each kind vary
-
in general terms, hydrogen atoms enter a fuel cell at the anode where a chemical reaction strips them of their electrons. The hydrogen atoms are now “ionized,” and carry a positive electrical charge. The negatively charged electrons provide the current through wires to do work. If alternating current (AC) is needed, the DC output of the fuel cell must be routed through a conversion device called an inverter.
- ...6 more annotations...
-
But in general terms, hydrogen atoms enter a fuel cell at the anode where a chemical reaction strips them of their electrons. The hydrogen atoms are now �ionized,� and carry a positive electrical charge. The negatively charged electrons provide the current through wires to do work. If alternating current (AC) is needed, the DC output of the fuel cell must be routed through a conversion device called an inverter.
-
Every fuel cell also has an electrolyte, which carries electrically charged particles from one electrode to the other, and a catalyst, which speeds the reactions at the electrodes. Hydrogen is the basic fuel, but fuel cells also require oxygen. One great appeal of fuel cells is that they generate electricity with very little pollution–much of the hydrogen and oxygen used in generating electricity ultimately combine to form a harmless byproduct, namely water.
-
A fuel cell is a device that generates electricity by a chemical reaction. Every fuel cell has two electrodes, one positive and one negative, called, respectively, the anode and cathode. The reactions that produce electricity take place at the electrodes.
-
fuel cell is a device that generates electricity by a chemical reaction. Every fuel cell has two electrodes, one positive and one negative, called, respectively, the anode and cathode.
-
One detail of terminology:
-
Oxygen enters the fuel cell at the cathode and, in some cell types (like the one illustrated above), it there combines with electrons returning from the electrical circuit and hydrogen ions that have traveled through the electrolyte from the anode. In other cell types the oxygen picks up electrons and then travels through the electrolyte to the anode, where it combines with hydrogen ions. The electrolyte plays a key role. It must permit only the appropriate ions to pass between the anode and cathode. If free electrons or other substances could travel through the electrolyte, they would disrupt the chemical reaction. Whether they combine at anode or cathode, together hydrogen and oxygen form water, which drains from the cell. As long as a fuel cell is supplied with hydrogen and oxygen, it will generate electricity. Even better, since fuel cells create electricity chemically, rather than by combustion, they are not subject to the thermodynamic laws that limit a conventional power plant (see "Carnot Limit" in the glossary). Therefore, fuel cells are more efficient in extracting energy from a fuel. Waste heat from some cells can also be harnessed, boosting system efficiency still further
-
"A fuel cell is a device that generates electricity by a chemical reaction. Every fuel cell has two electrodes, one positive and one negative, called, respectively, the anode and cathode. The reactions that produce electricity take place at the electrodes." -
"A fuel cell is a device that generates electricity by a chemical reaction. Every fuel cell has two electrodes, one positive and one negative, called, respectively, the anode and cathode."
6More
Environmental, economic, and energetic costs and benefits of biodiesel and ethanol biof... - 0 views
-
Negative environmental consequences of fossil fuels and concerns about petroleum supplies have spurred the search for renewable transportation biofuels.
-
To be a viable alternative, a biofuel should provide a net energy gain, have environmental benefits, be economically competitive, and be producible in large quantities without reducing food supplies.
-
Ethanol yields 25% more energy than the energy invested in its production, whereas biodiesel yields 93% more. Compared with ethanol, biodiesel releases just 1.0%, 8.3%, and 13% of the agricultural nitrogen, phosphorus, and pesticide pollutants, respectively, per net energy gain. Relative to the fossil fuels they displace, greenhouse gas emissions are reduced 12% by the production and combustion of ethanol and 41% by biodiesel. Biodiesel also releases less air pollutants per net energy gain than ethanol.
- ...3 more annotations...
-
Even dedicating all U.S. corn and soybean production to biofuels would meet only 12% of gasoline demand and 6% of diesel demand. Until recent increases in petroleum prices, high production costs made biofuels unprofitable without subsidies. Biodiesel provides sufficient environmental advantages to merit subsidy. Transportation biofuels such as synfuel hydrocarbons or cellulosic ethanol, if produced from low-input biomass grown on agriculturally marginal land or from waste biomass, could provide much greater supplies and environmental benefits than food-based biofuels.
-
We use these criteria to evaluate, through life-cycle accounting, ethanol from corn grain and biodiesel from soybeans.
-
These advantages of biodiesel over ethanol come from lower agricultural inputs and more efficient conversion of feedstocks to fuel. Neither biofuel can replace much petroleum without impacting food supplies.
4More
How Much Solar Energy Can We Harvest? - 2 views
-
The sun delivers about 7000 times more energy than we currently consume globally. However, we cannot cover the whole surface of the Earth with solar energy collectors. How much of this energy can we collect? Will it be enough to replace fossil fuels?
-
Our global consumption of electricity in 2005 was 15,182 TWh/y (see The Little Green Handbook). However, 9,541 TWh/y of electricity was produced by fossil fuels and 2,555 TWh/y by nuclear power, or the total 12,096 TWh/y. Assuming the lowest solar potential and the lowest efficiency of solar cells we can calculate that we could produce 35 times more electricity than produced by fossil fuels and nuclear power. The additional advantage is that solar power is clean and last practically forever.
-
Even if we used only 1% of unused land area we could produce nearly 4 times more electricity than we produce using fossil fuels and nuclear power.
6More
EIA Energy Kids - Hydropower - 1 views
-
Tides are caused by the gravitational pull of the moon and sun, and the rotation of the Earth. Near shore, water levels can vary up to 40 feet due to tides. Dam of the Tidal Power Plant on the Estuary of the Rance River, Bretagne, France Source: Stock photography (copyrighted) Tidal power is more predictable than wind energy and solar power. A large enough tidal range — 10 feet — is needed to produce tidal energy economically.
-
The United States has no tidal plants and only a few sites where tidal energy could be produced economically. France, England, Canada, and Russia have much more potential to use this type of energy.
-
Tidal turbines are basically wind turbines in the water that can be located anywhere there is strong tidal flow. Because water is about 800 times denser than air, tidal turbines have to be much sturdier than wind turbines. Tidal turbines are heavier and more expensive to build but capture more energy.
- ...2 more annotations...
-
Waves are caused by the wind blowing over the surface of the ocean. There is tremendous energy in the ocean waves. It's estimated that the total potential off the coasts of the United States is 252 billion kilowatthours a year, about 6% of the United States' electricity consumption in 2010. The west coasts of the United States and Europe and the coasts of Japan and New Zealand are good sites for harnessing wave energy.
-
Many more ways to capture wave energy are currently under development. Some of these devices being developed are placed underwater, anchored to the ocean floor, while others ride on top of the waves. The world's first commercial wave farm using one such technology opened in 2008 at the Aguçadora Wave Park in Portugal.
-
Stay Online on the worldwide web on the worldwide web on the world wide web online on the world wide web online roulette from Modern contemporary modern sydney, Fun and Free! Now you is able of doing Real "www.funlivecasino.com.au" Stay Online on the worldwide web on the worldwide web on the world wide web online on the world wide web online roulette for Fun in Modern contemporary modern sydney on a product new web page, FunLiveCasino.com.au. Using the newest on the worldwide web working technology, Fun Stay Gambling house allows you be a factor of a genuine action occurring on a genuine desk in a genuine betting house, all approved on Live! You can see other real gamers in the betting house betting on the same outcomes you do providing you greatest believe in in the outcomes as they are not designed 'just for you a, like other action being affected by products such as 'live studios' or pc designed actions. Its awesome to think when your really in the betting house that you might be on digicam, and individuals on the worldwide web might be watching! The long run is scary! Believe one day soon this will be the only way individuals would bet on the worldwide web because the worldwide web is complete of fraudsters, you have to be extremely cautious, and why would you perform Online Online on the worldwide web on the worldwide web on the world wide web online on the world wide web online roulette any other way except from a Real Gambling house you can assess out, see, pay interest to and trust! Amazingly this web page is definitely 100 % 100 % 100 % 100 % 100 % 100 % 100 % free and has no determining upon up process, no junk, no pc bunny rabbit bunny rabbit rabbit mouse mouse clicks and no stress. Just Immediate Fun "www.funlivecasino.com.au" 100 % 100 % 100 % 100 % 100 % 100 % 100 % free Stay Roulette! Give it a try, its value verifying out! "www.funlivecasino.com.au" Australia's Online Fun Stay Casino! Backlink designed from http://fiverr.c
9More
Energy Resources: Geothermal power - 0 views
-
Geothermal energy has been used for thousands of years in some countries for cooking and heating.
-
How it works
-
Hot rocks underground heat water to produce steam. We drill holes down to the hot region, steam comes up, is purified and used to drive turbines, which drive electric generators.
- ...5 more annotations...
-
Advantages Geothermal energy does not produce any pollution, and does not contribute to the greenhouse effect.
-
Once you've built a geothermal power station, the energy is almost free. It may need a little energy to run a pump, but this can be taken from the energy being generated.
-
The big problem is that there are not many places where you can build a geothermal power station. You need hot rocks of a suitable type, at a depth where we can drill down to them. The type of rock above is also important, it must be of a type that we can easily drill through.
-
Hazardous gases and minerals may come up from underground, and can be difficult to safely dispose of.
-
Is it renewable? Geothermal energy is renewable. The energy keeps on coming, as long as we don't pump too much cold water down and cool the rocks too much
-
Most quality online stores. Know whether you are a trusted online retailer in the world. Whatever we can buy very good quality. and do not hesitate. Everything is very high quality. Including clothes, accessories, bags, cups. Highly recommended. This is one of the trusted online store in the world. View now www.retrostyler.com
16More
EIA Energy Kids - Wind - 1 views
-
Wind is simply air in motion. It is caused by the uneven heating of the Earth's surface by the sun. Because the Earth's surface is made of very different types of land and water, it absorbs the sun's heat at different rates. One example of this uneven heating can be found in the daily wind cycle.
-
The Daily Wind Cycle During the day, the air above the land heats up more quickly than the air over water. The warm air over the land expands and rises, and the heavier, cooler air rushes in to take its place, creating wind. At night, the winds are reversed because the air cools more rapidly over land than over water. In the same way, the atmospheric winds that circle the earth are created because the land near the Earth's equator is heated more by the sun than the land near the North and South Poles. Wind Energy for Electricity Generation Today, wind energy is mainly used to generate electricity. Wind is a renewable energy source because the wind will blow as long as the sun shines
-
Like old fashioned windmills, today’s wind machines (also called wind turbines) use blades to collect the wind’s kinetic energy. The wind flows over the blades creating lift, like the effect on airplane wings, which causes them to turn. The blades are connected to a drive shaft that turns an electric generator to produce electricity. With the new wind machines, there is still the problem of what to do when the wind isn't blowing. At those times, other types of power plants must be used to make electricity.
- ...12 more annotations...
-
Wind Production In 2010, wind turbines in the United States generated about 2% of total U.S. electricity generation. Although this is a small fraction of the Nation's total electricity production, it was equal to the annual electricity use of about 8.7 million households.
-
Operating a wind power plant is not as simple as just building a windmill in a windy place. Wind plant owners must carefully plan where to locate their machines. It is important to consider how fast and how much the wind blows at the site
-
As a rule, wind speed increases with altitude and over open areas that have no windbreaks. Good sites for wind plants are the tops of smooth, rounded hills, open plains or shorelines, and mountain gaps that produce wind funneling.
-
Conditions are well suited along much of the coasts of the United States to use wind energy. However, there are people who oppose putting turbines just offshore, near the coastlines, because they think the wind turbines will spoil the view of the ocean. There is a plan to build an offshore wind plant off the coast of Cape Cod, Massachusetts.
-
Wind is a renewable energy source that does not pollute, so some people see it as a good alternative to fossil fuels.
-
Since early recorded history, people have been harnessing the energy of the wind. Wind energy propelled boats along the Nile River as early as 5000 B.C.
-
As late as the 1920s, Americans used small windmills to generate electricity in rural areas without electric service. When power lines began to transport electricity to rural areas in the 1930s, local windmills were used less and less,
-
In the early 1980s, wind energy really took off in California, partly because of State policies that encouraged renewable energy sources.
-
Wind is a clean source of energy, and overall, the use of wind for energy has fewer environmental impacts than using many other energy sources. Wind turbines (often called windmills) do not release emissions that pollute the air or water (with rare exceptions), and they do not require water for cooling. They may also reduce the amount of electricity generated from fossil fuels and therefore reduce the amount of air pollution, carbon dioxide emissions, and water use of fossil fuel power plants.
-
Modern wind turbines are very large machines, and some people do not like their visual impact on the landscape.
-
Some people do not like the sound that wind turbine blades make. Some types of wind turbines and wind projects cause bird and bat deaths. These deaths may contribute to declines in species that are also being affected by other human-related impacts.
-
Most wind power projects on land also require service roads that add to their physical impact on the environment.
-
Most quality online stores. Know whether you are a trusted online retailer in the world. Whatever we can buy very good quality. and do not hesitate. Everything is very high quality. Including clothes, accessories, bags, cups. Highly recommended. This is one of the trusted online store in the world. View now www.retrostyler.com
4More
What is Tidal Energy? | Renewable Green Energy Power - 0 views
-
It was used in the watermills along the shores of England during the Roman age and also used along the shores of France and Spain. This period was around 900 AD. The water rising from the tides was impounded in barrages and it was allowed to flow through waterwheels and other energy capturing devices thus capturing the energy and converting it into useful work used to grind grains and produce flour. The first tidal mill in the US was built in Salem, MA in 1635.
-
In recent history it was not until the 1960s that a tidal energy plant was built in France, on the estuary of La Rance, to capture the tidal energy and produce electricity. The plant has been operating for the past 50 or so years producing electricity without missing a tide. The second tidal energy plant was built about 20 years later in 1982 in Nova Scotia, Canada.
-
Water is much denser than air and this means that the tidal energy turbines would be much smaller than the wind energy turbines needed for the production of the same amount of electricity.
- ...1 more annotation...
-
produced by the rise and fall of tides which occur in all parts of the world.
10More
Advantages and Disadvantages Of Wave Energy - 0 views
-
Wave energy is as source of power that comes from the endless march of the waves as they roll into the shore then back out again. Humans harness this power along the coastal regions of the United States, Canada, Scotland, and Australia. Energy that comes from the waves in the ocean sounds like a boundless, harmless supply.
-
Advantages of Wave Energy 1. Renewable: The best thing about wave energy is that it will never run out. There will always be waves crashing upon the shores of nations, near the populated coastal regions. The waves flow back from the shore, but they always return. Unlike fossil fuels, which are running out, in some places in the world, just as quickly as people can discover them. Unlike ethanol, a corn product, waves are not limited by a season. They require no input from man to make their power, and they can always be counted on
-
Also unlike fossil fuels, creating power from waves creates no harmful byproducts such as gas, waste, and pollution. The energy from waves can be taken directly into electricity-producing machinery and used to power generators and power plants nearby. In today’s energy-powered world, a source of clean energy is hard to come by.
- ...7 more annotations...
-
Another benefit to using this energy is its nearness to places that can use it. Lots of big cities and harbors are next to the ocean and can harness the power of the waves for their use. Coastal cities tend to be well-populated, so lots of people can get use from wave energy plants.
-
A final benefit is that there are a variety of ways to gather it. Current gathering methods range from installed power plant with hydro turbines to seafaring vessels equipped with massive structures that are laid into the sea to gather the wave energy.
-
The biggest advantages of wave power as against most of the other alternative energy sources is that it is easily predictable and can be used to calculate the amount that it can produce. The wave energy is consistent and proves much better than other sources which are dependent on wind or sun exposure.
-
The biggest disadvantage to getting your energy from the waves is location. Only power plants and towns near the ocean will benefit directly from it. Because of its source, wave energy is not a viable power source for everyone. Landlocked nations and cities far from the sea have to find alternate sources of power, so wave energy is not the clean energy solution for everyone.
-
As clean as wave energy is, it still creates hazards for some of the creatures near it. Large machines have to be put near and in the water to gather energy from the waves. These machines disturb the seafloor, change the habitat of near-shore creatures (like crabs and starfish) and create noise that disturbs the sea life around them. There is also a danger of toxic chemicals that are used on wave energy platforms spilling and polluting the water near them.
-
Another downside is that it disturbs commercial and private vessels. Power plants that gather wave energy have to be placed by the coastline to do their job, and they have to be near cities and other populated areas to be of much use to anybody. But these are places that are major thoroughfares for cargo ships, cruise ships, recreational vehicles and beach goers. All of these people and vessels will be disrupted by the installation of a wave energy gathering source. This means that government officials and private companies that want to invest in wave energy sources have to take into account and consider the needs of those they may be disturbing.
-
Wind power is highly dependent on wavelength i.e. wave speed, wave length, wavelength and water density. They require a consistent flow of powerful waves to generate significant amount of wave power. Some areas experience unreliable wave behavior and it becomes unpredictable to forecast accurate wave power and therefore cannot be trusted as reliable energy source.
6More
Wind Power - 0 views
-
We have been harnessing the wind's energy for hundreds of years. From old Holland to farms in the United States, windmills have been used for pumping water or grinding grain. Today, the windmill's modern equivalent - a wind turbine - can use the wind's energy to generate electricity.
-
Wind turbines, like windmills, are mounted on a tower to capture the most energy. At 100 feet (30 meters) or more aboveground, they can take advantage of the faster and less turbulent wind. Turbines catch the wind's energy with their propeller-like blades. Usually, two or three blades are mounted on a shaft to form a rotor.
-
A blade acts much like an airplane wing. When the wind blows, a pocket of low-pressure air forms on the downwind side of the blade. The low-pressure air pocket then pulls the blade toward it, causing the rotor to turn. This is called lift. The force of the lift is actually much stronger than the wind's force against the front side of the blade, which is called drag. The combination of lift and drag causes the rotor to spin like a propeller, and the turning shaft spins a generator to make electricity.
- ...1 more annotation...
-
Wind turbines can be used as stand-alone applications, or they can be connected to a utility power grid or even combined with a photovoltaic (solar cell) system. For utility-scale sources of wind energy, a large number of wind turbines are usually built close together to form awind plant. Several electricity providers today use wind plants to supply power to their customers.
-
Today, the windmill's modern equivalent - a wind turbine - can use the wind's energy to generate electricity. -
Today, the windmill's modern equivalent - a wind turbine - can use the wind's energy to generate electricity.
3More
Tidal Energy : Advantages and Disadvantages - 0 views
-
Advantages of Tidal Energy1) It is an inexhaustible source of energy. 2) Tidal energy is environment friendly energy and doesn't produce greenhouse gases. 3) As 71% of Earth’s surface is covered by water, there is scope to generate this energy on large scale. 4) We can predict the rise and fall of tides as they follow cyclic fashion. 5) Efficiency of tidal power is far greater as compared to coal, solar or wind energy. Its efficiency is around 80%. 6) Although cost of construction of tidal power is high but maintenance costs are relatively low. 7) Tidal Energy doesn’t require any kind of fuel to run. 8) The life of tidal energy power plant is very long. 9) The energy density of tidal energy is relatively higher than other renewable energy sources.
-
Disadvantages of Tidal Energy 1) Cost of construction of tidal power plant is high. 2) There are very few ideal locations for construction of plant and they too are localized to coastal regions only. 3) Intensity of sea waves is unpredictable and there can be damage to power generation units. 4) Influences aquatic life adversely and can disrupt migration of fish. 5) The actual generation is for a short period of time. The tides only happen twice a day so electricity can be produced only for that time. 6) Frozen sea, low or weak tides, straight shorelines, low tidal rise or fall are some of the obstructions. 7) This technology is still not cost effective and more technological advancements are required to make it commercially viable. 8) Usually the places where tidal energy is produced are far away from the places where it is consumed. This transmission is expensive and difficult. Tidal Energy is thus a clean source of energy and doesn’t require much land or other resources as in harnessing energy from other sources. However, the energy generated is not much as high and low tides occur only twice a day and continuous energy production is not possible.
