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kramerjac99

Tidal Energy Ltd » The Technology - 0 views

  • Tidal energy is a form of hydropower that converts the energy of the tides into electricity or other useful forms of power. The tide is created by the gravitational effect of the sun and the moon on the earth. Tidal energy is therefore a predictable form of renewable energy, which can be harnessed in two forms:
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    what it is.
dpurdy

What makes geothermal energy clean? - Curiosity - 0 views

  • The water that creates the energy ultimately returns to the Earth, where it can be used again.
olearydev99

Climate: Facts, dangers and what you can do | Environmental Defense Fund - 0 views

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    "Scientists track changes to the planet's temperature in many ways. Land-based weather stations and ocean buoys in every corner of the world monitor temperatures constantly."
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.
smithkai143

What environmental benefits does tidal energy have compared to the traditional fossil fuel energy production? | Answerbag - 0 views

  • A benefit is very little pollution. However, there is a very serious potential draw back. It can be very hard of fish populations. The proposal for tidal power is to put turbines on the bottom of a bay and let the water rushing in and out with the tide turn them and generate electricity. However, along with the water will come fish and other marine animals. What do you think will happen when these critters get sucked into the turbines. Can you say sushi, boys and girls? Putting some kind of screen in front of the turbine to prevent this would just mean that the animals would be sucked up against the screens, obstructing the flow of water through the turbines.
troisichr99

Research Report: what are the best uses for solar power - 1 views

  • A quick search on TreeHugger shows that ' solar power ' most often occurs in connection with producing electricity and only secondarily in connection with solar water heaters
  • Compared to electrically heated Water , Solar Water Heating is 57% of the internal rate of return, the scientists found
giumarraant99

Hydrogen Fuel Cell | Yale Office of Sustainability - 1 views

  • At 250 kilowatts, the fuel cell produces 40-50% of the electricity for the Environmental Science Center. Its electricity production alone is 47% effective, and the addition of heat recovery allows for up to 60% efficiency
  • While designed to run on pure hydrogen, Yale’s fuel cell is actually powered by natural gas, 80% of which is usable hydrogen. The fuel cell takes in natural gas and water and produces water, electricity, and hot air.
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    Explains what this energy source is best suited for and how this energy source reduces other forms of pollution
Connor Wiggins

Fuel Cells Information, Fuel Cells Facts, Fuel Cells Technology - National Geographic - 0 views

  • A fuel cell is a device that uses a source of fuel, such as hydrogen, and an oxidant to create electricity from an electrochemical process.
  • Most fuel cells in use today, however, use hydrogen and oxygen as the chemicals.
  • Although hydrogen is the most abundant element in the universe, it is difficult to store and distribute. Canisters of pure hydrogen are readily available from hydrogen producers, but as of now, you can't just fill up with hydrogen at a local gas station.
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  • All fuel cells have the same basic configuration; an electrolyte and two electrodes. But there are different types of fuel cells, based mainly on what kind of electrolyte they use.
  • All fuel cells have the same basic configuration; an electrolyte and two electrodes. But there are different types of fuel cells, based mainly on what kind of electrolyte they use.
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    According to many experts, we may soon find ourselves using fuel cells to generate electrical power for all sorts of devices we use every day
espercla98

What is photon? - Definition from WhatIs.com - 1 views

  • Modern physicists have demonstrated that the energy in any electromagnetic field is made up of discrete packets. The term photon (meaning "visible-light particle") has been coined for these energy packets.
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    "The term photon (meaning "visible-light particle")"
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.
smithree98

Hydrogen Fuel-Cell Vehicles - Is Hydrogen the Fuel of the Future? - 1 views

  • The benefits of ditching fossil fuels for hydrogen are many, of course. Burning fossil fuels like coal, natural gas and oil to heat and cool our buildings and run our vehicles takes a heavy toll on the environment, contributing significantly to both local problems such as elevated particulate levels and global ones such as a warming climate. The only by-product of running a hydrogen-powered fuel cell is oxygen and a trickle of water, neither of which will cause any harm to human health or the environment.
  • But right now, 95 percent of the hydrogen available in the United States is either extracted from fossil fuels or made using electrolytic processes powered by fossil fuels, thus negating any real emissions savings or reduction in fossil-fuel usage. Only if renewable energy sources—solar, wind and others—can be harnessed to provide the energy to process hydrogen fuel can the dream of a truly clean hydrogen fuel be realized.
  • They concluded that we’d lower greenhouse gas emissions more by driving gasoline/electric hybrid cars than by driving fuel-cell cars run on hydrogen from coal. Hydrogen made using natural gas would fare a little bit better in terms of pollution output, while making it from wind power would be a slam-dunk for the environment.
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  • many reasons, ranging from safety to cost to lack of demand.
  • Another problem is the lack of hydrogen refueling stations
  • replacing the fossil fuels responsible for global warming and various nagging forms of pollution.
  • they are spending upwards of $1 million to produce each one due to the advanced technology involved and low production runs. Toyota hopes to reduce its costs per fuel-cell vehicle to around $50,000 by 2015
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    says most things about hydrogen and what it does
eldredzac98

What is Biofuel? - 1 views

  • Biofuels or biodiesels are fuels that are, in essence, biodegradable and non-toxic. They are manufactured from vegetable oils, waste cooking oils, animal fats or tall oil (a by-product of the pulp and paper industry).
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    They are manufactured from vegetable oils, waste cooking oils, animal fats or tall oil (a by-product of the p
wellsann99

Wind Power History - 0 views

  • It development of technology have been well proven over the years of time. When the sun emit heat to warm of the Earth it would be unbearable without wind. Wind widely disperses the heat making it bearable for all living things to survive. Without wind nothing would exist, it would just like all the other planets uninhibited by human nature or any living things for that matter.
  • A wind turbine is a machine that transforms kinetic energy from the wind into mechanical energy.
  • Wind power was first used in ancient times with the sail boat.
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  • When windmills were first developed they were used to assist man with the chores of pumping and grinding.
  • Well wind power is the transformation of energy from wind to electricity or other forms of energy
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    what wind power is
conboyeri98

Fuel cell - Wikipedia, the free encyclopedia - 0 views

  • A fuel cell is a device that converts the chemical energy from a fuel into electricity through a chemical reaction with oxygen or another oxidizing agent.[1] Hydrogen is the most common fuel, but hydrocarbons such as natural gas and alcohols like methanol are sometimes used. Fuel cells are different from batteries in that they require a constant source of fuel and oxygen to run, but they can produce electricity continually for as long as these inputs are supplied
  • A fuel cell is a device that converts the chemical energy from a fuel into electricity through a chemical reaction with oxygen or another oxidizing agent.
  • A fuel cell is a device that converts the chemical energy from a fuel into electricity through a chemical reaction with oxygen or another oxidizing agent.[1] Hydrogen is the most common fuel, but hydrocarbons such as natural gas and alcohols like methanol are sometimes used. Fuel cells are different from batteries in that they require a constant source of fuel and oxygen to run, but they can produce electricity continually for as long as these inputs are supplied.
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  • A fuel cell is a device that converts the chemical energy from a fuel into electricity through a chemical reaction with oxygen or another oxidizing agent
  • There are many types of fuel cells, but they all consist of an anode (negative side), a cathode (positive side) and an electrolyte that allows charges to move between the two sides of the fuel cell.
  • The principle of the fuel cell was discovered by German scientist Christian Friedrich Schönbein in 1838
  • Stationary fuel cells are used for commercial, industrial and residential primary and backup power generation. Fuel cells are very useful as power sources in remote locations, such as spacecraft, remote weather stations, large parks, communications centers, rural locations including research stations, and in certain military applications. A fuel cell system running on hydrogen can be compact and lightweight, and have no major moving parts. Because fuel cells have no moving parts and do not involve combustion, in ideal conditions they can achieve up to 99.9999% reliability.[49] This equates to less than one minute of downtime in a six-year period.
  • Although there are currently no Fuel cell vehicles available for commercial sale, over 20 FCEVs prototypes and demonstration cars have been released since 2009. Demonstration models include the Honda FCX Clarity, Toyota FCHV-adv, and Mercedes-Benz F-Cell.[64] As of June 2011 demonstration FCEVs had driven more than 4,800,000 km (3,000,000 mi), with more than 27,000 refuelings.[65]
  • A fuel cell is a device that converts the chemical energy from a fuel into electricity through a chemical reaction with oxygen or another oxidizing agent.[1] Hydrogen is the most common fuel, but hydrocarbons such as natural gas and alcohols like methanol are sometimes used.
  • The fuel cell he made used similar materials to today's phosphoric-acid fuel cell.
  • In 2003, U.S. President George W. Bush proposed the Hydrogen Fuel Initiative (HFI). This aimed at further developing hydrogen fuel cells and infrastructure technologies with the goal of producing commercial fuel cell vehicles. By 2008, the U.S. had contributed 1 billion dollars to this project
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    "A fuel cell is a device that converts the chemical energy from a fuel into electricity through a chemical reaction with oxygen or another oxidizing agent.[1] Hydrogen is the most common fuel, but hydrocarbons such as natural gas and alcohols like methanol are sometimes used. Fuel cells are different from batteries in that they require a constant source of fuel and oxygen to run, but they can produce electricity continually for as long as these inputs are supplied."
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    Explains what a fuel cell is.
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    "Individual fuel cells produce relatively small electrical potentials, about 0.7 volts, so cells are "stacked", or placed in series, to increase the voltage and meet an application's requirements.[2] In addition to electricity, fuel cells produce water, heat and, depending on the fuel source, very small amounts of nitrogen dioxide and other emissions. The energy efficiency of a fuel cell is generally between 40-60%, or up to 85% efficient if waste heat is captured for use."
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    "A fuel cell is a device that converts the chemical energy from a fuel into electricity through a chemical reaction with oxygen or another oxidizing agent.[1] Hydrogen is the most common fuel, but hydrocarbons such as natural gas and alcohols like methanol are sometimes used."
dpurdy

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.
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  • 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.
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dpurdy

EIA Energy Kids - Geothermal - 3 views

  • Geothermal Basics What Is Geothermal Energy? The word geothermal comes from the Greek words geo (earth) and therme (heat). So, geothermal energy is heat from within the Earth. We can recover this heat as steam or hot water and use it to heat buildings or generate electricity. Geothermal energy is a renewable energy source because the heat is continuously produced inside the Earth.
  • Geothermal energy is generated in the Earth's core. Temperatures hotter than the sun's surface are continuously produced inside the Earth by the slow decay of radioactive particles, a process that happens in all rocks. The Earth has a number of different layers:
  • Where Geothermal Energy is Found The ring of fire goes around the edges of the Pacific. The map shows that volcanic activity occurs around the Pacific rim.Source: National Energy Education Development Project (Public Domain) Naturally occurring large areas of hydrothermal resources are called geothermal reservoirs. Most geothermal reservoirs are deep underground with no visible clues showing above ground. But geothermal energy sometimes finds its way to the surface in the form of: Volcanoes and fumaroles (holes where volcanic gases are released) Hot springs Geysers
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  • U.S. Geothermal Is Mostly in the West Most of the geothermal reservoirs in the United States are located in the western States and Hawaii.
  • Electricity generation power plants require water or steam at very high temperature (300° to 700°F). Geothermal power plants are generally built where geothermal reservoirs are located within a mile or two of the surface.
  • The United States Is the Leader in Geothermal Power Generation The United States leads the world in electricity generation with geothermal power.  In 2009, U.S. geothermal power plants produced 15 billion kilowatt-hours (kWh), or 0.4% of total U.S. electricity generation.  In 2009, five States had geothermal power plants:
  • Geothermal power plants use hydrothermal resources that have two common ingredients: water (hydro) and heat (thermal). Geothermal plants require high temperature (300°F to 700°F) hydrothermal resources that may come from either dry steam wells or hot water wells.
  • high-pressure hot water from deep inside the Earth and convert it to steam to drive the generator turbines. When the steam cools, it condenses to water and is injected back into the ground to be used over and over again. Most geothermal power plants are flash steam plants.
  • Geothermal Power Plants Have Low Emission Levels Geothermal power plants do not burn fuel to generate electricity, so their emission levels are very low. They release less than 1% of the carbon dioxide emissions of a fossil fuel plant. Geothermal plants use scrubber systems to clean the air of hydrogen sulfide that is naturally found in the steam and hot water. Geothermal plants emit 97% less acid rain-causing sulfur compounds than are emitted by fossil fuel plants. After the steam and water from a geothermal reservoir have been used, they are injected back into the Earth.
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    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
bakereli00

What are Biofuels? - 0 views

  • Biofuels are liquid fuels which have been derived from other materials such as waste plant and animal matter. There are two main types of biofuels – bioethanol and biodiesel. Bioethanol is used as a replacement for gasoline and biodiesel is used as a replacement for diesel.
mannixjul00

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.
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  • produced by the rise and fall of tides which occur in all parts of the world.
westkea00

Wave power: how it works | SmartPlanet - 0 views

  • What is wave power? Wave power is renewable energy derived from ocean waves. It is the kinetic energy of wind interacting with water and creating waves
  • Wave energy is generated by the wind
  • The best wave energy environments are along western coastlines because the largest, most consistent winds come from the west,
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  • How does wave power work? Most of the energy comes from the rising and falling water level and requires exposure to the waves
  • There might never be a dominant technology for harnessing this power
  • because of the differences in potential wave energy sites throughout the world.
  • all ocean energy resources, including wave power, would combine to create energy 800 times more powerful than wind
  • Currently, wind is our biggest renewable energy source
  • What are the benefits of wave power? Because wave devices tend to be on the surface and don’t have propellers, as tidal power technologies do, some believe they will create less environmental damage than other renewable energy technologies,
  • There are advantages compared to wind in that the devices are smaller and don’t have the visual profile that wind turbines have.”
dpurdy

What Is Geothermal? | GoGoGeo - 0 views

  • The short answer to this question is that Geothermal Energy is a type of renewable energy that is generated and stored within the Earth.
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