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Tidal power plant in India, First of its kind ! Gujarat tidal energy, mnre tidal energy, tidal energy india potential, tidal energy market in india, gulf of cambay, sunderbans tidal energy, tidal stream devices, tidal barrage, tidal stream generator, wave energy, tidal barrage, tidal stream decices,

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Gujarat goes for tidal power at Rs 15 per unit ?!
AHMEDABAD: More than two years after Gujarat government dropped the idea of producing tidal wave power in the Gulf of Khambhat because it was "too costly", the stateenergy department has revived it. While officials suggested before going ahead with it the government would "look into technical issues", a government resolution (GR) has been issued claiming it is "possible to produce tidal wave power at two spots - in the Gulf of Kutch near Mandva, and in the Gulf of Khambhat near Hazira."


GR, significantly, says that at the two spots, respectively, 200 MW and 300 MW of "tidal wavepower can be produced". The decision to drop tidal wave power project was taken in early 2009 after the state government decided to slash down the cost of the Kalpasar project, proposed as a sweet water lake by damming the Gulf of Khambhat. While reviving the project, the GR said, Rs 25 crore have been set aside and handed over to the Gujarat Power Corporation Ltd to begin with the project.

The GR said, "In village Maska in taluka Mandvi, Kutch district, 16 hectares (ha) area has been acquired to kick-start the tidal wave project. The National Institute of Oceanography, Goa, has been asked to carry out marine environment impact assessment for tidal wavepower." Meanwhile, Rs 25 crore have been set aside for soil investigation, topographical survey and geotechnical survey of the sea. Also, studies are being carried out on the type of turbines needed for tidal wave project.

"The Gujarat government is has already entered into a preliminary agreement with US firm Atlantis for starting a 50 MW tidal wave power project at either of the two spots, but preferably in the Gulf of Kutch", a senior official said, adding, "While the state fisheries department and Gujarat Maritime Board have cleared the project, it is lying for a nod with the environment department for over a year."

Sources said, details furnished by Atlantis suggest that cost of one MW in putting up tidalwave power project would Rs 17.1 crore, which includes the cost of the turbine, sub-station equipment, power electronics equipment, cabling and installation. This is if Atlantis puts up a 50 MW tidal project. But in case in case it proposes a 250 MW project, the cost would go down to Rs 14.1 crore.

Tariff of the power to be produced from tidal wave would be Rs 15 per unit, the sources said, which suggests that the Gujarat government would be required to give a massive subsidy for 20 to 25 years in the same as it has done to solar power projects. There is, however, no decision on the matter. "The matter will be looked into in case more firms show in putting up tidal power projects", the official said.

Wave & Tidal Energy

 

India is yet to make any significant progress in exploiting wave and tidal energy sources.

*Tidal energy potential in India

Total available potential

Total identified potential: about 9000 MW

 

West Coast

ü  Gulf of Cambay (7000 MW)

ü  Gulf of Kutch (1200 MW)

 

East Coast

ü  The Ganges Delta in the Sunderbans in West Bengal for small scale tidal power development. Estimates peg the potential in this region to be about 100 MW

Exploited potential of tidal energy in india

ü  The Gujarat state government has approved Rs 25 crore for setting up the 50 MW plant at the Gulf of Kutch. The government has signed a MoU with Atlantis Resource Corporation to setup the plant.

ü  The Gujarat government last year also approved a 10 MW tidal energy plant proposed by Urja Global Limited in association with a US-based company Ocean Energy Industries.

ü  MNRE sanctioned a demonstration project for setting up 3.75 MW capacity tidal energy power plant at the Durgaduani Creek in Sunderbans region

 

Projected capacity of tidal energy in india

No clear projections as capacity additions would be largely driven by policy adopted

Government incentives for tidal energy in india

None at the moment, but India’s Ministry of New and Renewable Energy said in Feb 2011 that it may provide financial incentives for as much as 50 percent of the cost for projects seeking to demonstrate tidal power.

Investments in tidal energy in india

ü  Negligible, currently

ü  In Jan 2011, the state of Gujarat announced plans to install Asia’s first commercial-scale tidal current power plant; the state government approved the construction of a 50 MW project in the Gulf of Kutch. In April 2012, Rs. 25 crores has been approved for the construction of this project.

Challenges for tidal energy in india

üLong development timescales (some technologies have remainedat the development stage for decades)

üHigh capital cost

üLack of infrastructure for connection of the system to the grid

üEnvironmental issues arising out of the cable laying and other construction works

üIntermittent supply – tidal power plants provide power for only around 10 hours each day – when the tide is actually moving in or out

üRegional limitations – tidal power plants require a basin or gulf that has mean tidal amplitude of 7m or above for efficient generation

Cost of power generation of tidal energy in india

Global estimates put the price of generation at 13-15 cents/kWh (no Indian estimates available)

 

 Wave Energy in India

 

Total available potential of wave energy in India

The potential along the 6000 Km of India’s coast is estimated to be about 40,000 MW – these are preliminary estimates. This energy is however less intensive than what is available in more northern and southern latitudes.

 

Exploited potential of Wave energy in india

India built its first seas surface energy harvesting technology demonstration plant in Vizhinjam, near Thiruruvananthpuram.

 

Projected capacity of wave energy in india

 

No commercial projects

 

Government incentives for wave energy in india

None

 

Investments

Negligible; some preliminary efforts being made in the state of Gujarat.

 

Challenges for wave energy 

ü  Lack of clarity about the potential

ü  Technology immaturity

ü  High costs

ü  Lack of clear policy and incentive package from the government

ü  Low energy density

 

Cost of power generation

 

        Wave Power – Potential for Short and Medium Term Growth: Low

        Tidal Power – Potential for Short and Medium Term Growth: Low


 

Global estimates put the price of generation at 15-17 cents/kWh (no Indian cost estimates available)

 

 

 

 

Predicting waves could double ocean energy capture and tidal energy capture too

Put simply, some waves are better than others. To tackle this problem and to get the most out of the waves coming their way, researchers have been working on technology to predict wave power.

We already mentioned this development here at EarthTechling. Now the same team, which is being led by the University of Exeter, in western England, has published research claiming new methods for predicting waves could double current energy capture.

The study was carried out by mathematicians and engineers from the University of Exeter and Tel Aviv University.

The research focused mainly on point absorbers, commonly-used floating devices with parts that move in response to waves, generating energy which they feed back to the grid.

The key to the making the point absorbers work better, the researchers said, was to try and ensure their response matched as closely as possible the force of the waves.

By predicting the force of the oncoming wave and ensuring the energy capture device responded accordingly, this would also limit the likelihood of the device being damaged and mean it would not need to be turned off in stormy conditions, as is currently the case.

Improving the efficiency of wave technology could have significant repercussions for future energy needs, particularly in the United Kingdom.

Marine energy is believed to have the potential to provide the UK with its electricity needs twice over. At present, however, technologies to extract and convert energy from the sea are far less advanced than other renewables, such as solar and wind, and remain as yet largely uncommercial without the intervention of government subsidy.

The University of Exeter is collaborating with Ocean Power Technologies (OPT), a wave energy device developer, to exploit and further develop the results from this research.

OPT wants to use the prediction models in its PowerBuoy wave energy systems. According to OPT, this technology would allow the PowerBuoy to fine-tune its electronic capabilities to better "prepare" for the shape and size of waves as they approach, significantly boosting the power output of the PowerBuoy, and reducing the cost of the energy it produces. more

and more 3/7/12





*When it comes to development Gujarat leads. It already has a double digit growth every year. Gujarat leads the nation in solar energy
.And now here is another first from Modi's Gujarat.
Tidal power plant ! First of its kind in India. Atleast so they say !

 
 London-based Atlantis Resources Corporation and the Gujarat government was signed  an agreemnet. They have studied and  identified the Gulf of Kutch along India�s western coast as ideal  for tidal power generation.  
Tidal power uses turbines to harness the energy contained in the flow of ocean tides.The project currently is estimated to be generate 50 MW and can be enhanced to 250 MW
The project - the first of its kind in the country - will generate 50 megawatts of power.  But its capacity can be increased to 250 megawatts

The Gujarat government is all set to develop India’s first tidal energy plant. The state government has approved Rs 25 crore for setting up the 50 MW plant at the Gulf of Kutch. It will produce energy from the ocean tides.

The state government signed a MoU with Atlantis Resource Corporation last year to develop the plant. “The proposal was approved in this year’s budget session,” says Rajkumar Raisinghani, senior executive with Gujarat Power Corporation Limited (GPCL). Atlantis Resource Corporation is a UK-based developer of tidal current turbines. “The equipment has been imported and work will start anytime soon. We are awaiting Coastal Regulation Zone clearance from Ministry of Environment and Forests, which is expected soon,” adds Raisinghani.

According to the GPCL officials, if this 50 MW plant is successfully commissioned, its capacity will be increased to 200 MW.  As per a study conducted by Atlantis Resource Corporation and the state government two years ago, the Gulf of Kutch has a total potential of 300 MW. The biggest operating tidal station in the world, La Rance in France, generates 240 MW.

 

According to the estimates of the Indian government, the country has a potential of 8,000 MW of tidal energy. This includes about 7,000 MW in the Gulf of Cambay in Gujarat, 1,200 MW in the Gulf of Kutch and 100 MW in the Gangetic delta in the Sunderbans region of West Bengal.  more

Wave Energy Device Tested In Black Sea

 

Israel-based wave power designer and manufacturer Eco Wave Power (EWP) has completed the first open water phase of testing for its new wave energy device. The company said it successfully installed a medium-scale wave energy power plant in the Black Sea during April.

The latest phase of testing follows on from the initial lab-based testing of the device at the Institute of Hydromechanics in Kiev, Ukraine, at the end of last year.

 

wclapper

 

 

During the Black Sea trial EWP examined the characteristics of two different floater shapes, the “Wave Clapper” and the “Power Wing”, as well as measuring of the energy output of the devices under different wave heights and frequencies. The company also looked at the influence of side waves on the floaters, examined the effect of putting floaters in close proximity to each other, and tested the floaters’ storm-protection mechanisms.  more 3/7/12

Tidal Energy

 

The objective of the tidal energy programme is to study, testing and assessment of the potential of tidal energy in the country and to harness it for power generation.
It is nice to see that government of India  has a group head handling tidal energy.

 

Among the various forms of energy contained in the seas and oceans, tidal energy, has been developed on a commercial scale. India has a long coastline with the estuaries and gulfs where tides are strong enough to move turbines for electrical power generation. The Gulf of Cambay and the Gulf of Kutch in Gujarat on the west coast have the maximum tidal range of 11m and 8m with average tidal range of 6.77m and 5.23m respectively. The Ganges Delta in the Sundarbans is approximately 5m with an average tidal range of 2.97m. The identified economic power potential is of the order of 8000 MW with about 7000 MW in the Gulf of Cambay, about 1200 MW in the Gulf of Kachchh in the State of Gujarat and about 100 MW in the Gangetic Delta in the Sunderbans region in the State of West Bengal.

 

 

The most attractive locations are the Gulf of Cambay and the Gulf of Kachchh on the west coast where the maximum tidal range is 11 m and 8 m with average tidal range of 6.77 m and 5.23 m respectively. The Ganges Delta in the Sunderbans in West Bengal also has good locations for small scale tidal power development. The maximum tidal range in Sunderbans is approximately 5 m with an average tidal range of 2.97 m.

The identified economic tidal power potential in India is of the order of 8000-9000 MW with about 7000 MW in the Gulf of Cambay about 1200 MW in the Gulf of Kachchh and less than 100 MW in Sundarbans.

 

The Ministry sanctioned a project for setting up a 3.75 MW demonstration tidal power plant at Durgaduani Creek in Sunderbans, West Bengal to the West Bengal Renewable Energy Development Agency (WBREDA), Kolkata. The National Hydro Power Corporation Ltd. (NHPC) is executing the project on a turnkey basis.

The State Government of Gujarat formed a Special Purpose Vehicles (SPVs) with public private partnership and sponsored a study for large scale exploitation of tidal energy across the coastline of Gujarat. This study is based on one of the advanced technologies developed so for. In this technology kinetic energy of tidal currents has been proposed to be harnessed under the water and along the flow of water and without using the conventional methods like water wheel or other types of turbines.

source

 

Shri Alok Srivastava
Joint Secretary

 

is the group head in MNRE in charge of tidal energy.

 

 

Off : 91-11-24361027
Fax : 91-11-24367413
Res : 91-11-23015544
Email : srivastava[dot]alok[at]nic[dot]in

 

 

 

 

 


Sh B.L.Ram is the division head for tidal energy in mnre.

His id is blrlkmne[at]up[dot]nic[dot]in

 

 

 

 

 

Tidal power, also called tidal energy, is a form of hydropower that converts the energy of tides into useful forms of power - mainly electricity.

Although not yet widely used, tidal power has potential for future electricity generation. Tides are more predictable than wind energy and solar power. Among sources of renewable energy, tidal power has traditionally suffered from relatively high cost and limited availability of sites with sufficiently high tidal ranges or flow velocities, thus constricting its total availability. However, many recent technological developments and improvements, both in design (e.g. dynamic tidal powertidal lagoons) and turbine technology (e.g. new axial turbinescross flow turbines), indicate that the total availability of tidal power may be much higher than previously assumed, and that economic and environmental costs may be brought down to competitive levels.

Historically, tide mills have been used, both in Europe and on the Atlantic coast of North America. The incoming water was contained in large storage ponds, and as the tide went out, it turned waterwheels that used the mechanical power it produced to mill grain.  The earliest occurrences date from the Middle Ages, or even fromRoman times. It was only in the 19th century that the process of using falling water and spinning turbines to create electricity was introduced in the U.S. and Europe.

 

 

Encouraging results for wave energy project

 

The wave energy research project that is being conducted off the coast of Gozo is producing very encouraging results, sparking a lot of interest in Europe and hitting the international media, the Malta Council for Science and Technology said.

The project is funded by the council and the Technology National Research and Innovation programme and coordinated by DexaWave Energy Malta in collaboration with Euromed Eco Power, the Institute for Sustainable Energy and the International Ocean Institute Malta Operation Centre at the University.

The purpose of the project is to transfer technology to adapt a converter for Mediterranean from North Sea conditions. more 2/7/12

 

 

Commercial Status of Tidal Stream Devices (as on 2009)

CompanyClassTechnologyCountryYearStage
Aqua Marine Power Tidal Horizontal Axis Turbine UK 2007 Prototype
Verdant Power Tidal Horizontal Axis Turbine US 2000 Commercial
Marine Current Turbines Tidal Horizontal Axis Turbine UK 2000 Commercial
SMD Hydrovision Tidal Horizontal Axis Turbine UK 2003 Prototype
Open-Hydro Tidal Open Center Turbine Ireland 2006 Pre-Commercial
Hammerfest Strom Tidal Horizontal Axis Turbine Norway 2007 Pilot

source

 

 

 

 

 

 

Tidal power, also called tidal energy, is a form of hydropower that converts the energy of tides into useful forms of power - mainly electricity.

Although not yet widely used, tidal power has potential for future electricity generation. Tides are more predictable than wind energy and solar power. Among sources ofrenewable energy, tidal power has traditionally suffered from relatively high cost and limited availability of sites with sufficiently high tidal ranges or flow velocities, thus constricting its total availability. However, many recent technological developments and improvements, both in design (e.g. dynamic tidal powertidal lagoons) and turbine technology (e.g. new axial turbinescross flow turbines), indicate that the total availability of tidal power may be much higher than previously assumed, and that economic and environmental costs may be brought down to competitive levels.

 

 

  • Intermittent supply - Cost and environmental problems, particularly barrage systems are less attractive than some other forms of renewable energy. Global estimates put the price of generation at 13-15 cents/kWh (no Indian estimates available) 
  • Cost - The disadvantages of using tidal and wave energy must be considered before jumping to conclusion that this renewable, clean resource is the answer to all our problems. The main detriment is the cost of those plants.
  • The altering of the ecosystem at the bay - Damages like reduced flushing, winter icing and erosion can change the vegetation of the area and disrupt the balance. Similar to other ocean energies, tidal energy has several prerequisites that make it only available in a small number of regions. For a tidal power plant to produce electricity effectively (about 85% efficiency), it requires a basin or a gulf that has a mean tidal amplitude (the differences between spring and neap tide) of 7 meters or above. It is also desirable to have semi-diurnal tides where there are two high and low tides everyday. A barrage across an estuary is very expensive to build, and affects a very wide area - the environment is changed for many miles upstream and downstream. Many birds rely on the tide uncovering the mud flats so that they can feed. There are few suitable sites for tidal barrages.
  • Only provides power for around 10 hours each day, when the tide is actually moving in or out.
  • Present designs do not produce a lot of electricity, and barrages across river estuaries can change the flow of water and, consequently, the habitat for birds and other wildlife
  • Expensive to construct
  • Power is often generated when there is little demand for electricity 
  • Limited construction locations
  • Barrages may block outlets to open water. Although locks can be installed, this is often a slow and expensive process.

 

 

MNRE sanctions tidal energy pilot project

A study was undertaken for the assessment of tidal energy potential in the country. According to the study, country has a potential of 8,000 Mw of tidal energy. This includes about 7,000 Mw in the Gulf of Cambay and 1200 Mwin the Gulf of Kutch in Gujarat and about 100 Mw in the Gangetic Delta in the Sunderbans in West Bengal.

The ministry of new and renewable energy (MNRE) has sanctioned a demonstration project for setting up 3.75 Mw tidal energy power plant at the Durgaduani creek in Sunderbans to West Bengal Renewable Energy Development Agency (WBREDA) and will be executed by NHPC Ltd.

Gujarat government has formed a Special Purpose Vehicles (SPVs) with public private partnership and sponsored a study for large scale exploitation of tidal energy across the coastline of Gujarat. One MoU for 50 Mw tidal power project has been signed between UK’s Atlantis Resource Corp. and Gujarat Power Corporation Ltd.

The ministry considers providing financial incentives upto 50 per cent f the cost to the state government implementing agencies for the development of tidal energy projects on cost sharing basis as technology demonstration projects in accordance with its R&D policy guidelines.

 

Comparing with wind power energy and solar energy, tidal power seems not a big 

sustainable resource, but it is doing a fast-rate progress in recent decades. I can see a 

bright future of the tidal power and wave power (we can call them ocean energy) 

when we fix several problems. First we have to make the cost lower, so that it can be 

built in a large scale, hopefully, within six years of operation, the Blue Energy system 

will generate electricity at a competitive  rate of $US 0.04 per kWh, constantly 

trending downward; Secondly, the turbine has to be more effective, technology of its 

working process should be fully developed; the point with tidal power energy is that, 

we should never neglect the environment impacts of tidal power, we do need a way to 

solve the current problems.  more 

 

 

 

Tides play a very important role in the formation of

global climate as well as the ecosystems for ocean

habitants. At the same time, tides are a substantial

potential source of clean renewable energy for

future human generations. Depleting oil reserves,

the emission of greenhouse gases by burning coal, oil

and other fossil fuels, as well as the accumulation of

nuclear waste from nuclear reactors will inevitably

force people to replace most of our traditional

energy sources with renewable energy in the future.

Tidal energy is one of the best candidates for this approaching revolution. Development of new, efRcient, low-cost and environmentally friendly hydraulic energy converters suited to free-Sow waters, such

as triple-helix turbines, can make tidal energy available worldwide. This type of machine, moreover,

can be used not only for multi-megawatt tidal

power farms but also for mini-power stations with

turbines generating a few kilowatts. Such power

stations can provide clean energy to small communities or even individual households located near

continental shorelines, straits or on remote islands

with strong tidal currents. source

 

 Tidal energy fact sheet 

 

 

Advantages and disadvantages of tidal energy

The rise and fall of the tide is consistent, which makes it very predictable and reliable. Tidal energy does not depend on the weather. The making of electricity in this way is usually not very costly.



What are the disadvantages of Tidal energy?

Right now tides do not produce a lot of electricity so its not very efficient. Barrages across river estuaries can change the flow of the water, and because of that it is the place for birds and other wildlife to live, because of this, there are some wildlife that could be in danger.

 

 

 

 

What are the costs of tidal energy?

Tidal power is a form of low-head hydroelectricity and uses familiar low-head hydroelectric generating equipment, such as has been in use for more than 120 years. The technology required for tidal power is well developed, and the main barrier to increased use of the tides is that of construction costs. There is a high capital cost for a tidal energy project, with possibly a 10-year construction period. Therefore, the electricity cost is very sensitive to the discount rate.

The major factors in determining the cost effectiveness of a tidal power site are the size (length and height) of the barrage required, and the difference in height between high and low tide. These factors can be expressed in what is called a site's "Gibrat" ratio. The Gibrat ratio is the ratio of the length of the barrage in metres to the annual energy production in kilowatt hours (1 kilowatt hour = 1 KWH = 1000 watts used for 1 hour). The smaller the Gibrat site ratio, the more desireable the site. Examples of Gibrat ratios are La Rance at 0.36, Severn at 0.87 and Passamaquoddy in the Bay of Fundy at 0.92.

Offshore tidal power generators use familiar and reliable low-head hydroelectric generating equipment, conventional marine construction techniques, and standard power transmission methods. The placement of the impoundment offshore, rather than using the conventional "barrage" approach, eliminates environmental and economic problems that have prevented the deployment of commercial-scale tidal power plants.

Three projects (Swansea Bay 30 MW, Fifoots Point 30 MW, and North Wales 432 MW) are in development in Wales where tidal ranges are high, renewable source power is a strong public policy priority , and the electricity marketplace gives it a competitive edge. Q. What are some of the devices for tidal energy conversion? The technology required to convert tidal energy into electricity is very similar to the technology used in traditional hydroelectric power plants. The first requirement is a dam or "barrage" across a tidal bay or estuary. Building dams is an expensive process. Therefore, the best tidal sites are those where a bay has a narrow opening, thus reducing the length of dam which is required. At certain points along the dam, gates and turbines are installed. When there is an adequate difference in the elevation of the water on the different sides of the barrage, the gates are opened. This "hydrostatic head" that is created, causes water to flow through the turbines, turning an electric generator to produce electricity.

Electricity can be generated by water flowing both into and out of a bay. As there are two high and two low tides each day, electrical generation from tidal power plants is characterized by periods of maximum generation every twelve hours, with no electricity generation at the six hour mark in between. Alternatively, the turbines can be used as pumps to pump extra water into the basin behind the barrage during periods of low electricity demand. This water can then be released when demand on the system its greatest, thus allowing the tidal plant to function with some of the characteristics of a "pumped storage" hydroelectric facility.

What are some of the devices for tidal energy conversion?

The technology required to convert tidal energy into electricity is very similar to the technology used in traditional hydroelectric power plants. The first requirement is a dam or "barrage" across a tidal bay or estuary. Building dams is an expensive process. Therefore, the best tidal sites are those where a bay has a narrow opening, thus reducing the length of dam which is required. At certain points along the dam, gates and turbines are installed. When there is an adequate difference in the elevation of the water on the different sides of the barrage, the gates are opened. This "hydrostatic head" that is created, causes water to flow through the turbines, turning an electric generator to produce electricity.

Electricity can be generated by water flowing both into and out of a bay. As there are two high and two low tides each day, electrical generation from tidal power plants is characterized by periods of maximum generation every twelve hours, with no electricity generation at the six hour mark in between. Alternatively, the turbines can be used as pumps to pump extra water into the basin behind the barrage during periods of low electricity demand. This water can then be released when demand on the system its greatest, thus allowing the tidal plant to function with some of the characteristics of a "pumped storage" hydroelectric facility.

Why tidal energy?

The demand for electricity on an electrical grid varies with the time of day. The supply of electricity from a tidal power plant will never match the demand on a system. But, due to the lunar cycle and gravity, tidal currents, although variable, are reliable and predictable and their power can make a valuable contribution to an electrical system which has a variety of sources. Tidal electricity can be used to displace electricity which would otherwise be generated by fossil fuel (coal, oil, natural gas) fired power plants, thus reducing emissions of greenhouse and acid gasses.

source 

 

 

* TED conversations

Tidal Energy

What do you think about tidal energy? It's not a new idea, but it is one that I think could have potential for success - particularly in poor countries. 

In essence, tidal energy may consist of buoys (of some nature) connected to pistons and crankshafts secured to the sea-floors in areas with potent tides. As the buoys ride the waves the pistons turn and create mechanical power which is sent back to storage facilities onshore. 

Do you think this technology has potential? Do you think it can be efficient in producing energy? Is it too far-fetched?

 

http://www.ted.com/conversations/11950/tidal_energy.html?c=476899

 

 

 Environmental Damage. There is considerable effect on the ecosystem. The exchange of water volume between a basin and the sea is reduced, this leads to the potential for increased pollution, because pollution is left accumulating in the basin. Also, because the exchange of volume is reduced, salinity of the basin decreases and sediment accumulation increases. Basically, anything we place in the water can and does affect the ecosystem.

 Fish population. Even with the best barrage designs, fish mortality rate per pass through the barrage is about 15%. Solutions to resolves this problem have either failed or are too impractical and too expensive.

 Time of day. Tides are predictable, but power stations only generate power when the tide is flowing in or out of the basin, which only happens during certain times of the day.

 Economical. Startup costs to build a tidal energy plant is high, but the maintenance costs are very low. This means that you will not see profits for a few years, causing some investors to back out of the project. This can be seen as both an advantage and disadvantage, depending upon desired profit returns. source

 

 

 

Cost comparison of  1 kw of electricity generation using coal, natural gas, nuclear, tidal, solar, wind, biofuel, etc

 

 

Tidal power stations

 

 

[edit]Operational

The Rance Tidal Power Station.

The following table lists tidal power stations that are in operation as of August 2010.

 

StationCapacity (MW)CountryLocationCommRef
Annapolis Royal Generating Station 20  Canada 44°45′07″N 65°30′40″W 1984 [1]
Jiangxia Tidal Power Station 3.2  China 28°20′34″N 121°14′25″E 1980 [2][3]
Kislaya Guba Tidal Power Station 1.7  Russia 69°22′37″N 33°04′33″E 1968  
Rance Tidal Power Station 240  France 48°37′05″N 02°01′24″W 1966  
Sihwa Lake Tidal Power Station 254  South Korea 37°18′47″N 126°36′46″E 2011 [4][5]
Strangford Lough SeaGen 1.2  United Kingdom 54°22′04″N 05°32′40″W 2008  
Uldolmok Tidal Power Station 1.5  South Korea 34°32′07″N 126°14′06″E 2009 [6]



 

 

 

 

 

*   The first large-scale rollout of tidal energy generation, Scottland


Image1

A trial with one 30m turbine, the HS1000, anchored to the ocean floor in a fast-flowing channel near the Orkney Islands, raised one megawatt of electricity -- enough to power around 500 homes. Now, Scottish Power is planning on building two farms of turbines off the Scottish coast.

The project at the Sound of Islay should hopefully generate 10MW, and then the later project off Duncansby Head (the most northeasterly point of Scotland) should generate around 95MW. While individual turbines have been trialled across the world, the arrays will be the largest of their kind, with local communities having their power provided by renewable tidal sources.

The turbines -- built by Andritz Hydro Hammerfest, a Norwegian firm -- represent a tricky engineering challenge. Considerations for wild plants and fish means that the blades can't move too fast, and the turbines must be located in areas where there is a reliably fast current travelling at at least 2.5m/s (such as the Sound of Islay, a narrow passage between the Scottish mainland and the island of Jura).

Once a suitable location has been identified, a giant steel frame is lowered to the seabed and secured. The turbines are between 40 to 100 metres below the surface of the sea, so theoretically pose no danger to shipping. The turbines are designed to turn in both directions to generate power, giving a constant supply of electricity. Why cant we generate tidal energy for India ? 

With its long coast, it could be possible to get a large amount of energy from tidal for india. more

 

* Tidal energy over other energy sources - video

 

Dutch maritime contractor IHC Merwede has signed a deal with compatriot company Ecofys to buy its Wave Rotor technology, and will now form a new marine renewables division called IHC Tidal Energy.

IHC Merwede buys Wave Rotor and forms tidal-energy arm

more  and about the advantages of vertical axis over horizontal axiz in tidal energy

SeaPower Seeks Partner to Bring Tidal-Energy Generator to Market

 

 

 

On 30 May 2012, IHC Merwede signed an agreement to acquire Wave Rotor technology from Ecofys, which is renowned for its expertise in sustainable energy solutions. The official signing was made by Willem Steenge, Managing Director of IHC Tidal Energy, and Manon Janssen, Managing Director of Ecofys. Wave Rotor technology, which will be managed by the newly established company IHC Tidal Energy, enables IHC Merwede to further secure its position in the renewable market.

Patented technology
With this acquisition, IHC Merwede has secured highly developed knowledge and the patented Wave Rotor technology. In contrast to most tidal turbines, the Wave Rotor is vertically oriented. It converts power from tidal currents and wave motion directly into electricity. The technology is a patented innovation from Ecofys that has been developed over the past ten years and successfully demonstrated in a 30kW pilot plant in the Westerschelde.

After the Wave Rotor was developed, it was brought through the pre-commercial stage by OceanMill. The company proved that the technology has enormous potential and is commercially viable. IHC Tidal Energy has set its goal to successfully bring the acquired technology to market, enriching the world with proven tidal and wave energy converters.

Tidal and wave energy market
IHC Merwede has been active in the renewable energy sector for decades. The market for tidal and wave technology is relatively new, but IHC Merwede foresees a significant growth of activities in Europe, North America and Asia.

Willem Steenge says: “The acquisition of Wave Rotor technology enables IHC Merwede to launch a fully integrated system to generate electricity using tidal energy. IHC Merwede will contribute, as a reliable link in the chain of new energy and land reclamation, to the sustainability or our world. The investment in this emerging market also fits well into the company’s strategic portfolio.”

Manon Janssen adds: “Ecofys is very proud to transfer this innovative technology over to IHC Merwede. With its expertise and global presence, IHC Merwede will bring Wave Rotor technology to the next commercial phase. Ecofys expects that Wave Rotor technology will have a big impact on the world.”

Company profile IHC Merwede
IHC Merwede is focussed on the continuous development of design and construction activities for the specialist maritime sector. It is the global market leader for efficient dredging and mining vessels and equipment – with vast experience accumulated over decades – and a reliable supplier of custom-built ships and supplies for offshore construction. more

 

Tidal energy and wave energy

 

 

Tidal energy is a form of hydropower that converts the energy from tides into electricity.

Tidal power is predictable and relies on the gravitational pull of the moon and the sun to create currents in the oceans. Generating electricity from the tides in oceans is not widely used and there is an emerging marine renewable energy industry. The potential has been recognised since Roman times and in the Middle Ages with evidence of early tide mills found in Europe and on the Atlantic coast of America.

 

The first tidal power station was built at La Rance in France. It was commissioned in 1966 with an installed capacity of 240MW. The first tidal power site in North America is the 18 MW Annapolis Royal Generating Station, Nova Scotia, which opened in 1984. The first in-stream tidal current generator in North America was positioned at Race Rocks on Southern Vancouver Island in 2006.

 

There are two main types of tidal energy – tidal stream systems and barrages.

 

 

Tidal stream systems use the kinetic energy of the moving water to power turbines.

 

 

Barrages use the potential energy in the difference between the height of the high and low tides.

WAVE energy

 

Ocean waves are a tertiary form of solar energy. Due to the contours of the earth’s surface, there is unequal heating of the earth from the sun. This generates wind and wind blowing over water makes waves. Wave power refers to the energy of ocean waves and the capture of that energy to do useful work, including generating electricity, desalination processes and pumping water.  When the wind blows over the surface of offshore water, such as oceans and seas, waves are created by the progressive transference of energy from the wind. Wave energy is stored, concentrated wind energy.  The larger the wave, the more powerful it is. Wave power is determined by wave height, wave speed and water density. Almost 75% of the world’s surface is water. However, waves are a largely unexplored source of energy compared with the progress of solar and wind energy systems.

 

The Aguçadora Wave Farm is the world’s first multi-unit wave farm and the world’s first commercial wave energy project. It is located 5km off the Atlantic coastline of northern Portugal. When wave energy systems are placed five to ten kilometres from shore, it is possible to access the high energy levels found in deep swell waves

 

 

 

Ocean can produce two types of energy: thermal energy from the sun's heat, and mechanical energy from the tides and waves. The fact that the marine renewable sector is less well developed than other energy industries presents companies with both opportunities and challenges

 

 



 

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2 Comments

  • shankar
    shankar -



    In a written reply Indias minister of state for non-conventional energy sources estimated that over 15,000 MW of tidal power potential has been estimated in the country at Gulf of Kachh,  Gulf of Cambay in Gujarat and Durgaduani creek in Sunderbans in West Bengal. No other  tidal energy project has been installed in the country so far.
    Globally the major tidal power projects currently in operation are in France (240 MW), Canada (20 MW) and Russia (0.4 MW). Like

  • sysadmin
    sysadmin -


    Like

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