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dpurdy

Explainer: what are biofuels? | Biofuels | SBS World News - 0 views

  • The biofuel industry takes the chemical energy contained in organic materials and converts this into useful energy sources. However, it is not necessarily a sustainable industry. Daniel Tan explains.
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    Explanation of the form of bio fuels.
dpurdy

The hidden costs of fossil fuels - and biofuels, too - CSMonitor.com - 1 views

  • Climate considerations aside, damages wrought by ethanol made from corn were usually similar to, or even slightly worse, than damages from gasoline. That’s because of the extra energy needed to convert corn to biofuel.
mannixjul00

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.
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    "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."
dpurdy

How Does Tidal Power Work? - Energy Informative - 1 views

  • 450 TWh is the estimated yearly potential of electric power that can be produced from tidal energy. In addition to this comes a large and not yet estimated potential in river flows.
  • Tidal stream generators are very similar to wind turbines except their below the water surface instead of above or on land. The turbine and generator converts the movement of water coming from change in tide, the kinetic energy, into electricity. Water is 830 times denser than air and therefore can generate electricity at lower speeds than wind turbines.
dpurdy

Wave power conversion systems for electrical energy production | Leonardo ENERGY - 1 views

  • Sea waves have associated a form of renewable energy which can be captured by using a hydro mechanical device that in turn drives an electrical generator to produce electrical energy.
sopranodan99

Wave & Tidal Energy Technology | Renewable Northwest Project - 0 views

  • Potential
  • Wave energy resources are best between 30º and 60º latitude in both hemispheres, and the potential tends to be the greatest on western coasts
  • While no commercial wave or tidal projects have yet been developed in the United States, several projects are planned for the near future, including projects in the Northwest
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  • ‘Pelamis’ wave energy conversion devices and generates a combined 2.25 MW of electricity. OPD plans to expand the facility to produce 22.5 MW in 2007
  • The United States receives 2,100 terawatt-hours of incident wave energy along its coastlines each year, and tapping just one quarter of this potential could produce as much energy as the entire U.S. hydropower system.
  • Total Annual U.S. Incident Wave Energy 2,110 terrawatt-hours
  • The United States receives 2,100 terawatt-hours of incident wave energy along its coastlines each year, and tapping just one quarter of this potential could produce as much energy as the entire U.S. hydropower system
  • In addition to its abundant solar, wind and geothermal resources, the Pacific Northwest is also uniquely situated to capture the renewable energy of the ocean. Special buoys, turbines, and other technologies can capture the power of waves and tides and convert it into clean, pollution-free electricity. Like other renewable resources, both wave and tidal energy are variable in nature. Waves are produced by winds blowing across the surface of the ocean. However, because waves travel across the ocean, their arrival time at the wave power facility may be more predictable than wind. In contrast, tidal energy, which is driven by the gravitational pull of the moon and sun, is predictable centuries in advance.
  • The United States receives 2,100 terawatt-hours of incident wave energy along its coastlines each year, and tapping just one quarter of this potential could produce as much energy as the entire U.S. hydropower system
  • The Unit
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    the amount of 1/4 of energy around the coasts could be equal to the amount energy produced by hydropower
morehousejam98

Tidal Power - 0 views

  • A dam-like structure is constructed across an estuary to trap a high tide of water and then let it pass through turbines to generate electricity. The water flow can generate electricity on the falling tide only, or on the falling and rising tide.
baileyamb99

How Is Wave Energy Used to Generate Electricity? | eHow.com - 0 views

  • Earth is composed mainly of bodies of water---about 71 percent of the earth's surface is water. Ninety-seven percent of that is found in the oceans. Because the earth's surface is curved, the sun heats it unevenly. This causes winds to blow across the water and generate waves. The sun and moon also exert their gravitational pull on the earth, triggering wave-producing tides. Wave motion energy can be harnessed and generated into electricity.
pettitmat99

Biofuels - 0 views

  • Biofuels are basically any fuel that can be burned in air to produce heat that is produced by biological means, normally by plant growth. Currently the most prominant biofuels are ethanol and bio-deisel because these can be burned in existing internal combustion engines and are thus a direct replacement for oil. The most important biofuel historically is wood with oth
  • Biofuels are currently cheaper than oil although this is only because we are seeing very high oil prices at the moment. Under what might be termed more 'normal' market conditions, biofuels lack any meaningful price advantage. Biofuel production is very labor intensive and very land intensive. Production of ethanol from sugar cane was pioneered by the Brazilians in the 1970's as a solution to an oil import bill they could ill afford. It worked for them as they have plenty of land they can convert to growing sugar cane and at the time, plenty of cheap labor with which to harvest it.
  • he simple truth is the world does not have enough land to produce anywhere near the quantity of biofuels we need to make any dent in our oil consumption. They are only in fashion now oil prices are high and it is cost effective to produce them. Sooner or later food prices will rise to such a point that biofuel production will cease to be economic.
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  • In any case the current price of oil is unlikely to be sustained. Much of today's oil prices can be attributed to the geopolitical situation in the Middle East and the hording of oil both for security of supply and more recently as a hedge against the falling dollar.
  • e they cheaper than oil? That depends how you calculate the cost!
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    "But herein lies the first problem with biofuels. They may be carbon nuetral but they are certainly not as green as they might be. Not if the land to grow sugar is coming from cutting down the Amazon jungle and not if vast quantities o"
pettitmat99

Alternative Fuels Data Center: Biodiesel Production and Distribution - 0 views

    • pettitmat99
       
      great photo on the production of biodeisels
  • he production process converts oils and fats into chemicals called long-chain mono alkyl esters, or biodiesel. These chemicals are also referred to as fatty acid methyl esters, and t
  • Biodiesel is produced from vegetable oils, yellow grease, and tallow.
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  • Raw or refined plant oil, or recycled greases that have not been processed into biodiesel, are not biodiesel and should be avoided
  • Fats and oils (triglycerides) are much more viscous than biodiesel, and low-level vegetable oil blends can cause long-term engine deposits, ring sticking, lube-oil gelling, and other maintenance problems that can reduce engine life
  • Biodiesel is distributed from the point of production to retail fueling stations by truck, train, or barge.
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    good website to find most information on biofuels
hughesacam99

Wave Energy Pros and Cons - Tidal and Ocean Wave Power Still Niche Technologies | Green... - 2 views

  • Wave Power is quite immature,costly and unproven in large scale. While some companies have made good progress, the technology remains largely unproven and has only been put to actual test in pilot cases.
  • While Wave Energy has been known since the 1700s the progress has been extremely slow.
  • One of the biggest problems of Renewable Power is that it is intermittent in nature as it generates energy only when there are waves. This problem can be solved with energy storage however this leads to additional costs.
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  • Severe Weather like Storms and Typhoons can be quite devastating on the Wave Power Equipment especially those place on the Sea Floor.
  • This is a disadvantage which is common to all  the 3 types of Water based Energy that is Tidal, Hydro and Waver Energy. Some forms of Energy are just better suited to some places.
  • Wave Power generate power quite far away from the consumption of electricity. Transportation of Wave Energy can be quite cumbersome and expensive. Some Wave Energy Generators are converting power at the bottom of the ocean or far away from the shoreline. Moving that power towards where it is used can be difficult.
  • The sight of wave generators around the shoreline can look quite ugly and cause loss of tourism potential around shorelines. Also local residents can have problems even with wave power equipment which is not far offshore. The Cape Wind Energy project off the shore of Massachusetts has been delayed by over 10 years as it has drawn serious objections from the owners of coastal homes about loss in their property values.
  • A Wave Power Plant can cost around$6-10 million million to be spent in building 1 Megawatt.
  • Waver Energy does not require any fuel like most other sources of energy
  • Wave Energy is powered by the waves of the ocean which are totally free just like Wind and Sunlight.
  • Wave Energy Generators can be installed in various sizes with as little as 1 MW. This is not possible for other energy forms which require a minimum large size such as Coal, Nuclear etc.
janosjus99

NREL: Learning - Biofuels Basics - 0 views

  • Unlike other renewable energy sources, biomass can be converted directly into liquid fuels, called "biofuels," to help meet transportation fuel needs
  • Today, ethanol is made from starches and sugars, but NREL scientists are developing technology to allow it to be made from cellulose and hemicellulose,
combspat98

How Fuel Cells Work - 1 views

    • combspat98
       
      pictue and descripiton of how fuel cells work
slentzkel99

Haldor Topsoe - Fuel cells for sustainable energy - 0 views

  • What is a fuel cell?A fuel cell produces electricity from fuel and air. The simplest fuel cell produces electricity from hydrogen and air with water as the only by-product.
  • Where can fuel cells be used?Fuel cells in general can be used in many different circumstances, depending on the type of fuel cell. Topsoe Fuel Cell focuses on SOFC fuel cells, which can be used in:Auxiliary power units (APUs) provide electricity where there is no access to grid power. Fuel cell based APUs can be used on, for instance, long-haul trucks to generate power during breaks.Micro combined heat and power units may be scaled to meet the electricity demand in single family households. Combined heat and power generation for households is one of the most efficient ways to meet residential energy requirements.Distributed generation using SOFC technology offers efficient power generation, for example hospitals, shopping malls, in apartment buildings and in areas with low power capacity.
phinneycha99

Photoelectric effect - Wikipedia, the free encyclopedia - 0 views

  • In the photoelectric effect, electrons are emitted from matter (metals and non-metallic solids, liquids or gases) as a consequence of their absorption of energy from electromagnetic radiation of very short wavelength and high frequency, such as ultraviolet radiation.
  • Light–matter interaction Low-energy phenomena: Photoelectric effect Mid-energy phenomena: Thomson scattering Compton scattering High-energy phenomena: Pair production
Connor Wiggins

HowStuffWorks "How Fuel Cells Work" - 0 views

  • This initiative, supported by legislation in the Energy Policy Act of 2005 (EPACT 2005) and the Advanced Energy Initiative of 2006, aims to develop hydrogen, fuel cell and infrastructure technologies to make fuel-cell vehicles practical and cost-effective by 2020
  • Why are governments, private businesses and academic institutions collaborating to develop and produce them? Fuel cells generate electrical power quietly and efficiently, without pollution. Unlike power
  • that use fossil fuels, the by-products from an operating fuel cell are heat and water
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  • With a fuel cell, chemicals constantly flow into the cell so it never goes dead -- as long as there is a flow of chemicals into the cell, the electricity flows out of the cell. Most fuel cells in use today use hydrogen and oxygen as the chemicals.
  • If you want to be technical about it, a fuel cell is an electrochemical energy conversion device. A fuel cell converts the chemicals hydrogen and oxygen into water, and in the process it produces electricity.
  • polymer electrolyte membrane fuel cells (PEMFC)
  • United States has dedicated more than one billion dollars to fuel cell research and development so far.So what exactly is a fuel cell,
  • With a fuel cell, chemicals constantly flow into the cell so it never goes dead -- as long as there is a flow of chemicals into the cell, the electricity flows out of the cell. Most fuel cells in use today use hydrogen and oxygen as the chemicals.
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    "In 2003, President Bush announced a program called the Hydrogen Fuel Initiative (HFI) during his State of the Union Address."
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    It shows how its sustainable 
labrumbra99

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.
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  • 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
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    "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."
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    "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."
dpurdy

Fuel Cells 2000 : Fuel Cell Basics : Applications - 0 views

  • There are many uses for fuel cells — right now, all of the major automakers are working to commercialize a fuel cell car. Fuel cells are powering buses, boats, trains, planes, scooters, forklifts, even bicycles. There are fuel cell-powered vending machines, vacuum cleaners and highway road signs. Miniature fuel cells for cellular phones, laptop computers and portable electronics are on their way to market. Hospitals, credit card centers, police stations, and banks are all using fuel cells to provide power to their facilities. Wastewater treatment plants and landfills are using fuel cells to convert the methane gas they produce into electricity. Telecommunications companies are installing fuel cells at cell phone, radio and 911 towers. The possibilities are endless.
  • Stationary
  • More than 2500 fuel cell systems have been installed all over the world
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  • Telecommunications
  • Landfills/Wastewater Treatment Plants/Breweries/Wineries-
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    Current Applications for fuel Cells
tillmanash98

Biofuel potential is bleak - 3 views

  • 12.48 billion gal of ethanol
  • The 2004 US corn crop totaled about 11.7 billion bushels,
  • The entire 2004 US corn and soybean crop, converted to biomass fuels, could replace about 10.41 billion gal of petroleum (7.6 billion as ethanol and 2.81 billion as biodiesel).
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  • The US consumed about 7.49 billion bbl of petroleum last year,
  • This means that the total biofuel potential of the record 2004 US corn and soybean harvests would offset about 12 days of US petroleum consumption, or about 3.3% of our total yearly petroleum consumption
  • Given that most of the US corn and soybean crop is already committed to other uses, this analysis indicates that biomass-based fuels will have a negligible role in reducing US petroleum consumption, which in turn underscores that replacing petroleum in the US economy will be a monumental challenge.
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    The 2004 US corn crop totaled about 11.7 billion bushels, the largest ever
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