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Tidal Power | BC Sustainable Energy Association - 1 views

  • However, estuaries are among the world’s most productive and sensitive ecosystems, and barrages cause large disruptions to their natural processes. We will therefore not further consider barrage based tidal power as a truly sustainable energy resource.
  • While there are non-tidal based ocean currents such as the Gulf Stream, those are usually too diffuse to be a practical energy source. The tides cause water to flow inwards from the ocean twice a day during flood tides, and outwards during ebb tides. Additional monthly and annual cycles vary the strength of this current on a monthly and annual basis. Narrow and shallow constrictions produce the fastest and most powerful movements, whose energy can be captured using submerged turbines.
  • BC Hydro’s 2002 Green Energy Study for BC estimated the realistic energy potential for tidal current energy generation in BC to be 20 TWhrs/year. The estimated cost was 11 cents/kWhr for a large (800 MW) site, and 25 cents/kWhr for a small (43 MW) site. The best sites are in the Strait of Georgia and Johnstone Strait, which are both relatively close to the main centers of consumption.
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  • The second type is based on utilizing the fast-flowing marine currents caused by tidal action. While there are non-tidal based ocean currents such as the Gulf Stream, those are usually too diffuse to be a practical energy source. The tides cause water to flow inwards from the ocean twice a day during flood tides, and outwards during ebb tides.
  • Nevertheless, it is a truly sustainable energy source which is also very predictable. It is not subject to the vagaries of weather or climate change, and while the energy varies, it follows a predictable pattern that is known many years in advance.
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    oceanic tides 
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    The second type is based on utilizing the fast-flowing marine currents caused by tidal action....it is a truly sustainable energy source which is also very predictable. It is not subject to the vagaries of weather or climate change, and while the energy varies, it follows a predictable pattern that is known many years in advance.
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    " costs are expected to fall to between 5 and 7 cents/kWhr."
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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."
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How is Wind Formed? - Answers.Ask.com - 0 views

  • Wind is formed when heats over a large area, causing the air to expand and causing a pressure change. When a low pressure system runs into a high pressure system, it causes a change in the air resulting in wind
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Solar energy - Wikipedia, the free encyclopedia - 3 views

  • Solar energy, radiant light and heat from the sun
  • radiant light and heat from the sun,
  • Solar energy, radiant light and heat from the sun, has been harnessed by humans since ancient times using a range of ever-evolving technologies. Solar energy technologies include solar heating, solar photovoltaics, solar thermal electricity, solar architecture and artificial photosynthesis, which can make considerable contributions to solving some of the most urgent energy problems the world now faces.[1] [2]
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  • "the development of affordable, inexhaustible and clean solar energy technologies will have huge longer-term benefits. It will increase countries’ energy security through reliance on an indigenous, inexhaustible and mostly import-independent resource, enhance sustainability, reduce pollution, lower the costs of mitigating climate change, and keep fossil fuel prices lower than otherwise. These advantages are global.
  • Solar technologies are broadly characterized as either passive solar or active solar depending on the way they capture, convert and distribute solar energy. Active solar techniques include the use of photovoltaic panels and solar thermal collectors to harness the energy. Passive solar techniques include orienting a building to the Sun, selecting materials with favorable thermal mass or light dispersing properties, and designing spaces that naturally circulate air.
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    The technologies of solar energy.
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    the advantages of solar energy for the world 
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Energy and Climate Change Research at The Institute of Energy Systems | School of Engin... - 0 views

  • Our results suggest that in both cases the energy and carbon intensities have low carbon footprint and are broadly competitive with commercial large wind turbines.
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Wind Energy and the Environment - Energy Explained, Your Guide To Understanding Energy ... - 0 views

  • 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. A few wind turbines have caught on fire, and some have leaked lubricating fluids, though this is relatively rare. 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. Many birds are killed from collisions with vehicles and buildings, by house cats and hunters, and by pesticides. Their natural habitats may be altered or destroyed by human development and by the changes in the climate that most scientists believe are caused by greenhouse gases emissions from human activities (which wind energy use can help reduce).
  • Making the metals and other materials in wind turbines and the concrete for their foundations requires the use of energy, which may be from fossil fuels.
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Tidal Wave Energy: New cutting edge technologies - 0 views

  • Tidal wave energy
  • Environmentally friendly power sources which are clean and do not cause pollution or environmental harm are the key to the future
  • one direction
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    What do we have to do to make this resource work for us in the future?
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How is solar energy converted into electrical energy - 0 views

  • Solar energy is very easyto change to electric energy. All you have to do is to take a solar cell. Put it in sunlight or other such source of light. It will use this light energy and will convert it into electric energy.
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    how solar energy is converted into electricity
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Geothermal energy environmental impact | Earth's Heat - 0 views

  • First of all, harnessing geothermal energy does not have the devastating impact on climate change like burning of the fossil fuels does. It is true that fluids drawn from the earth's core include greenhouse gases such as carbon dioxide and methane, but the amount of released greenhouse gas emissions is negligible compared to those from fossil fuel fired power plants.
  • One of the reasons for this is the fact that geothermal power plants are equipped with emission-control systems that reduce the exhaust.
  • geothermal power plants are connected with minimal freshwater and land requirements. This means that geothermal energy commonly has minimal impact on nearby ecosystems.
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  • Geothermal fluids contain elevated levels of certain toxic elements such as arsenic, mercury, lithium and boron, which means that geothermal plants need to be equipped with proper waste disposal units in order to ensure that the waste is disposed back into geothermal fields
    • dpurdy
       
      pollution from geothermal
  • constructing geothermal plant (which includes deep drilling) can affect land stability, and in some cases even trigger earthquakes (especially enhanced geothermal systems).
  • Geothermal power plants operate quietly meaning that they do not cause noise pollution.
  • It is often relatively easy to incorporate them into the existing environment without the obvious visual pollution because of their modest land requirements.
  • This natural source of energy provides efficient way to harness energy from with minimal impact on its surrounding environment.
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Solar Energy Facts: Solar Energy, Solar Cells, Solar Panels | Resourses - 0 views

  • For billions of years, the sun has poured out huge amounts of energy in several forms, including light, heat, radio waves, and even x-ray. The Earth, in orbit around the sun, intercepts a very small part of the sun’s immense output. On Earth, direct sunlight is available from sunrise until sunset, except during solar eclipses. Solar collectors and modules are designed to capture some of the sun’s energy and change it from radiation into more usable forms such as heat or electricity. In fact, sunlight is an excellent source of heat and electricity, the two most important forms of energy we consume.
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    solar energy facts
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Research Report: how does geothermal energy prevent climate chang3 - 0 views

  • Unlike a coal or Natural Gas plant, geothermal facilities do not need to purchase fuel to generate electricity
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Wind power - sustainable power generation from wind farms across the globe - 0 views

  • Wind power is safe, clean and increasingly affordable – with the potential for production on a much larger scale.Government support is crucial in ensuring the expansion of wind power. We believe such support should be transitional and limited. In the US, there is continuing uncertainty over the renewal of the production tax credit, which provides incentives to invest in wind energy. We are working with other wind energy suppliers to make an effective case for wind energy generation and the renewal of the production tax credit.Wind farms can provide large volumes of electricity (sometimes at a lower cost than conventional power generation)
  • Wind power is safe, clean and increasingly affordable – with the potential for production on a much larger scale.Government support is crucial in ensuring the expansion of wind power. We believe such support should be transitional and limited. In the US, there is continuing uncertainty over the renewal of the production tax credit, which provides incentives to invest in wind energy. We are working with other wind energy suppliers to make an effective case for wind energy generation and the renewal of the production tax credit.Wind farms can provide large volumes of electricity (sometimes at a lower cost than conventional power generation) Wind energy and the environment While wind farms can be an attractive alternative energy offering, they can also stir debate. During the planning stage for each new wind farm we assess the potential social and environmental impacts.The impact on wildlife and habitat The impact of wind farms on local residentsNoise from wind turbinesShadow flicker Interference with communications signalsWe then take steps to manage any negative impacts through engineering design changes, technology and other elements.
  • Wind power is safe, clean and increasingly affordable – with the potential for production on a much larger scale.Government support is crucial in ensuring the expansion of wind power. We believe such support should be transitional and limited. In the US, there is continuing uncertainty over the renewal of the production tax credit, which provides incentives to invest in wind energy. We are working with other wind energy suppliers to make an effective case for wind energy generation and the renewal of the production tax credit.
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Geothermal Energy | Energy and Global Climate Change in New England | US EP - 0 views

  • The constant temperature of the Earth creates underground sources of heat, hot water and steam which become fuel to produce geothermal energy. People have used various forms of geothermal energy for hundreds of years; modern technology accesses these underground reservoirs, steam deposits and hot air by drilling, and then using the heat or hot water directly or using it to create power. Geothermal energy represents an enormous, underused power source that provides clean, renewable energy in virtually unlimited supply.
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Fuel Cells for a Sustainable Future? | Tyndall°Centre for Climate Change Rese... - 0 views

  • >It is found that there are both technical and non technical barriers to the development of stationary fuel cells as a major component towards sustainable energy.
  • >It is found that there are both technical and non technical barriers to the development of stationary fuel cells as a major component towards sustainable energy.
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    "It is found that there are both technical and non technical barriers to the development of stationary fuel cells as a major component towards sustainable energy"
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Energy Source: Tidal Power | Renewable Energy & Efficiency | Pembina Institute - 0 views

  • idal power can be harnessed using a barrage (dam) built across an estuary that captures the potential energy generated by the change in height (or head) between high and low tides. As the tide goes in and out, the water flows through tunnels in the dam. The ebb and flow are used to either turn a water turbine or compress air through a pipe that then turns a turbine, which generates electricity. Tidal Fences and Turbines Tidal fences and turbines can also be used to capture tidal power. Tidal fences are turbines that operate like giant turnstiles, while tidal turbines are similar to wind turbines. In both cases, electricity is generated when the turbines are turned by the tidal currents that occur in coastal waters. Ocean currents generate relatively more energy than wind (air currents) because ocean water has a higher density than air and therefore applies greater force on the turbines.
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    how we use it.
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Unearthing the True Cost of Fossil Fuels : TreeHugger - 0 views

  • “true” cost of coal: Depending on how you factor in the costs of climate change, it could be between a few additional cents per kWh to a whopping ¢26.89 extra per kilowatt hour—the high-end estimate from the Harvard study. By way of comparison, the average American paid ¢11.54 per kWh on their residential electric bills last year.
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Climate Change: Causes - 0 views

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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.
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Wave Energy: an Overview (Oxfordshire Climate Exchange) - 1 views

  • Waves are generated by winds blowing over the ocean surface.  Wave energy is effectively a stored and concentrated form of solar energy since the winds that produce them are caused by pressure differences in the atmosphere caused by the sun's differential heating of the earth's surface. Waves can efficiently transport energy for thousands of miles and retain their energy long after the winds that first created them have died down, which makes waves one of the most concentrated and consistent sources of renewable energy. 
  • Globally, the potential use of wave power is, unsurprisingly, limited to areas of the world where there are waves. On a global scale, this is dictated by global wind patterns, with the result that waves are more prevalent in the mid-latitudes (40-60(N/S), than nearer the equator where the lack of ocean wind is referred to as the 'doldrums'.  Interestingly, this potential for wave power contrasts with that of solar power, which is more effective in lower latitudes
    • dpurdy
       
      Location of wave power.
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  • it is widely anticipated that other types of renewable resources, including wave energy, will need to be developed in order to meet more challenging targets beyond 2020. 
  • As with most renewable energy sources, wave devices have no emissions during generation but the energy associated with the construction of the device does have small associated emissions.
    • dpurdy
       
      What do we need to do in the future to make this work.
  • it is essential that the current demonstration schemes are successful, to reassure future investors. The most important objective is to deploy full-size demonstration schemes in order to gain greater confidence in the most developed technologies (as in the EU's Atlas project). 
  • it will be necessary to significantly improve the network connections to the electricity suppliers.
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