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dpurdy

Renewable Energy, Other sources of Renewable Energy - 0 views

www.altenergy.org/...other.html

wave infrastructure

shared by dpurdy on 22 Oct 12 - No Cached
  • "Worldwide, approximately 3000 gigawatts (1 gigawatt = 1 GW = 1 billion watts) of energy is continuously available from the action of tides.
  • The best areas are on the eastern sides of the oceans (western side of the continents) between the 40 and 60 latitudes in both the northern and southern hemispheres.
  • While the "wave power at deep ocean sites is three to eight times the wave power at adjacent coastal sites," constructing and mooring the site and transmitting the electricity to shore would be prohibitively costly.
  • ...1 more annotation...
  • There is a handful of wave energy demonstration plants operating worldwide, but none produces a significant amount of electricity.
  • dpurdy on 31 Oct 12
     
    While the "wave power at deep ocean sites is three to eight times the wave power at adjacent coastal sites," constructing and mooring the site and transmitting the electricity to shore would be prohibitively costly.
dpurdy

Devices that Harness Wave Energy | Wave Energy Cost - 0 views

www.oceanenergycouncil.com/...Wave-Energy.html

wave infrastructure

shared by dpurdy on 31 Oct 12 - No Cached
  • Because wave energy needs only 1/200 the land area of wind and requires no access roads, infrastructure costs are less;
  • dpurdy on 31 Oct 12
     
    "7. Because wave energy needs only 1/200 the land area of wind and requires no access roads, infrastructure costs are less;"
dpurdy

Winds, Waves, Tides - Ocean Energy | Environmental News, Articles & Information | Globa... - 2 views

www.ecoworld.com/...-waves-tides-ocean-energy.html

cost how what sustainable future

shared by dpurdy on 03 Nov 11 - No Cached
  • Can Already Cost Under $.06 per Kilowatt Hour * Pneumatic devices, such as the oscillating water column (OWC), use wave motion to compress and decompress air, and drive a turbine. * Float-based devices utilise a buoyant float moving with the waves, reacting against a sea bed anchor in order to harness energy. * Spillover devices utilise wave height to replenish a reservoir of seawater, which runs a turbine. * Raft-type devices use the relative motion of adjacent rafts or pontoons to harness wave energy. * Moving-body devices articulate in the water, inducing motion, which may be used to drive a hydraulic motor.
  • Tidal stream devices extract energy from the diurnal flow of tidal currents (caused by the gravitational pull of the moon). Unlike wind and wave power, tidal streams offer entirely predictable output. However, as the lunar cycle is of around 25 hours’ duration, the timing of peak outputs differs by around an hour each day and tidal energy cannot be guaranteed at times of peak demand.
  • However, several large grid-connected demonstration projects are expected to enter the water in the near future. Tidal stream is thus a few years behind wave energy.
  • ...3 more annotations...
  • Marine Current Turbines is about to field test a submerged 300 kW tidal turbine off Devon in the United Kingdom
  • The manufacturers of all these devices expect to deliver energy at a cost of 10-14 US cents per kWh, falling to below 6 US cents as experience grows and technologies mature
  • Power generation using wave energy is at a much earlier stage of development. Wave energy offers more predictable outputs than wind, but in early 2003 there was only around one megawatt of generating capacity installed worldwide, all of it essentially with demonstration prototypes. Proposed projects are likely to take this to about 6 MW over the next few years. The wave industry is characterised by a wide variety of novel devices
dpurdy

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

climatex.org/...wave-energy-overview

wave potential future how form history

shared by dpurdy on 30 Oct 12 - No Cached
  • 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
      dpurdy on 30 Oct 12
       
      Location of wave power.
  • ...5 more annotations...
  • 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
      dpurdy on 30 Oct 12
       
      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.
dpurdy

How we know human activity is causing warming | Environmental Defense Fund - 1 views

www.edf.org/...human-activity-causes-warming

pollution Fossil co2

shared by dpurdy on 30 Oct 12 - No Cached
  • The theory of global warming is nothing new. The Nobel Prize-winning chemist Svante Arrhenius first proposed the idea of global warming in 1896. Carbon dioxide, he knew, traps heat in the Earth's atmosphere. He also knew that burning coal and oil releases carbon dioxide (CO2).
dpurdy

Traditional Energy Sources vs. Green Power Sources | National Geographic - 2 views

greenliving.nationalgeographic.com/-green-power-sources-2442.html

pollution Fossil coal biofuel

shared by dpurdy on 20 Jan 12 - No Cached
  • Coal generates 2,249 pounds of carbon dioxide, 13 pounds of sulfur dioxide and 6 pounds of nitrogen oxides for every megawatt hour of energy generated.
  • Biomass produces nitrogen oxides and small amounts of sulfur dioxide. The amount of carbon dioxide produced does not exceed that of the Earth's normal carbon cycle and is considered negligible.
dpurdy

Hydrogen H2 - Fuel Cell Markets - Hydrogen H2 - 0 views

www.fuelcellmarkets.com/...4,1,1,2086.html

hydrogen form

shared by dpurdy on 30 Oct 12 - Cached
  • Hydrogen has the highest energy content of any common fuel by weight,
dpurdy

List of Tidal Power Plants and Future Tidal Stations- Facing Difficult Times | Green Wo... - 0 views

www.greenworldinvestor.com/...tations-facing-difficult-times

tidal future

shared by dpurdy on 30 Oct 12 - No Cached
  • Except for South Korea,not other government in the world is really pushing Tidal Wave Energy which needs massive government support at this stage of development.
  • Tidal Technology is still in the baby phase
  • Most of the tidal power plants using the modern tidal turbine technology are still in the pilot phase and generate negligible power.However tidal power stations have the potential to generate large amounts of energy in a non-polluting way
dpurdy

Visual Health Effects and Wind Turbines - The Society for Wind Vigilance - 0 views

www.windvigilance.com/...alth-effects-and-wind-turbines

wind disadvantages pollution

shared by dpurdy on 22 Oct 12 - No Cached
  • In addition to noise pollution wind turbines also have visual burdens.
  • The health impact of visual burdens cannot be underestimated. An epidemiology study conducted by World Health Organization determined a “bad view out of window” increased the risk for depression by 40%. The same study also demonstrated disturbance by noise and sleep disturbance by noise increased the risk of depression 40%, and 100% respectively.
  • Wind turbines produce noise and visual burdens.
  • ...3 more annotations...
  • Scientific research confirms visuals impacts can adversely affect human health.
  • Wind turbine shadow flicker has the potential to induce photosensitive epilepsy seizures however the risk is low with large modern models and if proper planning is adhered to.
  • Wind turbine shadow flicker induced adverse human health effects include annoyance and/or stress.
dpurdy

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

www.leonardo-energy.org/s-electrical-energy-production

wave convert

shared by dpurdy on 30 Oct 12 - No Cached
  • 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.
smithree98

Fuel cell - Wikipedia, the free encyclopedia - 1 views

en.wikipedia.org/...Fuel_cell

shared by smithree98 on 29 Oct 12 - No Cached
  • There were 140,000 fuel cell stacks shipped globally in 2010
  • although, as of 2010, no public company in the industry had yet become profitable
  • smithree98 on 29 Oct 12
     
    actually a pretty decent site to find info on hydrogen
smithkai143

Re: How is tidal power converted to electricity? - 0 views

www.madsci.org/...1017154685.Ph.r.html

tidal convert how electricity

shared by smithkai143 on 29 Oct 12 - No Cached
  • Tidal Energy originates from gravitational energy. Imagine you have a damn- like structure built along a river. During the high tide, the water flows into the river, causing the turbine to rotate and thus generating electricity. During the low tide, the water flows from the river to the sea, again, turning the turbine. (An electricity generating turbine consists of rotating wires surrounded by strong fixed magnetic field)
smithkai143

What environmental benefits does tidal energy have compared to the traditional fossil f... - 0 views

www.answerbag.com/721036

tidal form fossil fossil fuel fuel

shared by smithkai143 on 29 Oct 12 - No Cached
  • 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.
dpurdy

http://ec.europa.eu/research/energy/pdf/hlg_vision_report_en.pdf - 1 views

ec.europa.eu/...hlg_vision_report_en.pdf

hydrogen uses future co2

shared by dpurdy on 26 Oct 12 - No Cached
    • slentzkel99
      slentzkel99 on 26 Oct 12
       
      Report on hydrogen economy potential 
  • dpurdy on 26 Oct 12
     
    Challenges Producing hydrogen in the large quantities necessary for the transport and stationary power markets could become a barrier to progress beyond the initial demonstration phase.  Uses: Fuel cells will be used in a wide range of products, ranging from very small fuel cells in portable devices such as mobile phones and laptops, through mobile applications like cars, delivery vehicles, buses and ships, to heat and power generators in stationary applications in the domestic and industrial sector. Future energy systems will also include improved conventional energy converters running on hydrogen (e.g. internal combustion engines, Stirling engines, and turbines) as well as other energy carriers (e.g. direct heat and electricity from renewable energy, and bio-fuels for transport). 
dpurdy

HowStuffWorks "How Fuel Cells Work" - 1 views

auto.howstuffworks.com/...fuel-cell1.htm

hydrogen future potential uses history

shared by dpurdy on 26 Oct 12 - Cached
  • The fuel cell will compete with many other energy­ conversion devices, including the gas turbine in your city's power plant, the gasoline engine in your car and the battery in your laptop. Combustion engines like the turbine and the gasoline engine burn fuels and use the pressure created by the expansion of the gases to do mechanical work. Batteries convert chemical energy back into electrical energy when needed. Fuel cells should do both tasks more efficiently.
  • Sir William Grove invented the first fuel cell in 1839. Grove knew that water could be split into hydrogen and oxygen by sending an electric current through it (a process called electrolysis). He hypothesized that by reversing the procedure you could produce electricity and water. He created a primitive fuel cell and called it a gas voltaic battery. After experimenting with his new invention, Grove proved his hypothesis. Fifty years later, scientists Ludwig Mond and Charles Langer coined the term fuel cell while attempting to build a practical model to produce electricity.
  • carrowluk99 on 26 Oct 12
     
    " Combustion engines like the turbine and the gasoline engine burn fuels and use the pressure created by the expansion of the gases to do mechanical work. Batteries convert chemical energy back into electrical energy when needed. Fuel cells should do both tasks more efficiently."
phinneycha99

Energy and kids - 1 views

www.kids.esdb.bg/solar.html

solar how converted

shared by phinneycha99 on 26 Oct 12 - No Cached
  • phinneycha99 on 26 Oct 12
     
    "Photovoltaic cells, like batteries, generate direct current (DC) which is generally used for small loads (electronic equipment).  When DC from photovoltaic cells is used for commercial applications or sold to electric utilities using the electric grid, it must be converted to alternating current (AC) using inverters, solid state devices that convert DC power to AC. "
phinneycha99

Photoelectric effect - Wikipedia, the free encyclopedia - 0 views

en.wikipedia.org/...Photoelectric_effect

solar how converted

shared by phinneycha99 on 26 Oct 12 - Cached
  • 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
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