TIDAL ENERGY – ITS PROCESSES AND FUTURE PROSPECTS IN PAKISTAN

1. TIDAL ENERGY – ITS PROCESSES AND FUTURE PROSPECTS IN PAKISTAN BY: Durenayab khan

2. ALTERNATE ENERGY SOURCES • Availability of High Potential of renewable energy resources in Pakistan e.g. • Fossil Fuels • Nuclear plants • Solar Energy • City Solid Wastes • Wood wastes from Furniture • Agricultural Wastes • Forestry Wastes • Animal Slurry from farms • Waste from Chicken farms

3. TIDAL ENERGY TIDAL POWER SOMETIMES CALLED TIDAL ENERGY IS A FORM OF HYDROPOWER THAT EXPLOITS THE MOVEMENT OF WATER CAUSED BY TIDAL CURRENTS OR THE RISE AND FALL IN SEA LEVELS DUE TO TIDES .

4. CATEGORIES OF TIDAL POWER • TIDAL FLOW GENERATORS • Make use of Kinetic Energy from moving • water current to Power Turbines. • TIDAL BARRAGE POWER • Make use of Potential Energy from the • difference in height ( or head ) between • high and low tides

5. TIDAL PROCESS FLOW

7. ARTICLE # 1 The potential benefits of harnessing the powerful, rhythmic movement of the sea -- whether the up-and-down motion of waves or the ebb and flow of the tides -- to spin turbines and generate electricity has been recognized by mankind for some time. The New York Times, for instance, wrote in a 1921 article that "under the urgent need of checking the inroads on the world's resources of coal and oil ... actual projects are being pushed in three countries for the utilization of the Atlantic tides to produce hydroelectric power." Last fall (some 90 years later), Kate Galbraith, a Times energy reporter, wrote that "for years, technological visionaries have painted a seductive vision of using ocean tides and waves to produce power. But the technical difficulties of making such systems work are proving formidable."In short, ocean tides and waves represent potential energy sources whose time is -- and has long been -- yet to come. Still, the allure of tidal and wave power persists -- and for good reason. Ocean movements, spurred by the wind or the gravitational pull of the sun and moon, are eminently renewable, emissions-free energy sources.

8. According to the United States Department of Energy, some experts suggest that as much as 2 terawatts of electricity could be provided by ocean waves alone. In terms of watt-hours (the more familiar measure to anyone who receives an energy bill) the British Wind Energy Association -- a trade and professional body for the British wind and marine renewables industries -- estimates wave-power potential to be anywhere between 8,000 and 80,000 terawatt-hours annually.(Global annual electricity consumption is roughly 16,000 terawatt hours).Tidal power is a bit more limited in its potential. Only about 40 sites on the Earth present a large enough tidal differential -- that is, the difference between high and low tides -- to make electricity generation feasible, according to D.O.E.'s office of Energy Efficiency and Renewable Energy. But even here, experts suggest that, once the technological hurdles are overcome, tidal power has much going for it -- not least because its relationship to the forces exerted by the sun and moon make it arguably the most predictable potential energy source available.

9. Worth noting: A third type of power, called ocean thermal energy conversion, or O.T.E.C., exploits temperature differences between surface and deep waters -- confining its utility mainly to the tropics. The U.S. Energy Department, however, has pointed out that "some energy experts believe that if it could become cost-competitive with conventional power technologies, O.E.T.C. could produce billions of watts of electrical power."-- Tom Zeller Jr., (February 23, 2009) At present, about 100 small companies around the world -- many in Europe, where governments have subsidized the industry -- are working to develop ocean power. However, very little electricity is being generated from the ocean except at scattered test sites around the world.

10. ARTICLE # 2 The £3m turbine has been built into the seabed about a kilometer and a half (one mile) offshore from Lynmouth. The single 11 meter-long rotor blade will be capable of producing 300 kilowatts of electricity and will be a test-bed for further tidal turbines. It is hoped to convert the system to twin rotors by the end of next year. Project developers Marine Current Turbines Ltd and Cornwall-based Seacore hope to have the turbine hooked up to the national grid by the end of August. Martin Wright, of Marine Current Turbines Ltd, said: "We estimate that there is at least 10 gigawatts of power available from tidal power in the UK. "That's the same as about half of the existing nuclear industry." Energy pioneers have launched the world's first offshore tidal energy turbine off the Devon coast.

11. A marine current turbine looks like a smaller version of a modern windmill and the principle is exactly the same. But whereas a windmill draws energy from the movement of air, the marine turbine uses currents in the water. Its backers believe the concept can become a rival to wind power because ocean currents are more reliable than wind and also because they are less obtrusive; the structure is built on the seabed and projects just a few meters above the surface. There is no danger to fish because the blades rotate quite slowly - about 20 revolutions per minute. Several experimental devices working on similar principles have been built before, but the turbine unveiled in Devon is the first such permanent installation in the world to generate electricity. If it performs as expected, the consortium behind it hopes to build a whole set of turbines in the area - a tidal farm. The project is financed by the Department of Trade and Industry and the European Commission's energy programme. The turbine can be raised for maintenance SOURCE: BBC World News

12. PROS AND CONS • No Emissions • No Pollution • No Fossil Fuels • Renewable clean energy • Reduction in nuclear waste. • 365 days/24hr operational plant • Free and Abundant fuel ( Water ) • Expensive civil infrastructure & Time consuming • Improvements and research needed for Cost effective solution

13. TIDAL ENERGY POTENTIAL WORLD MAP

14. PROSPECTS OF TIDAL ENERGY IN PAKISTAN • 170Km available creek system of Indus Delta • Flow of water with high velocity during flood in Creek system • National Institute of Oceanography says sea water inundates up to 80Km at some places due to tidal fluctuations • 2-5 meters tidal heights at Korangi creek and over 5 meters at Sir Creek • Can produce 1100KW Power from a/m sites

15. PROSPECTS OF TIDAL ENERGY IN PAKISTAN • Baluchistan • Sonmiani Hor and Kalmat Khor are good prospects • Development of tidal Energy plants at Pakistan Coast could uplift socio-economic conditions of coastal population of Pakistan

16. OPERATING TIDAL POWER SCHEMES • Rance Tidal Power Plant at La Rance France ( 1960-1966 ) – 240MW Capacity • Annapolis Royal Generating Station in North America – 1984 – 18MW Capacity • Small Power Plant at Kislaya Guba on Barents Sea in former Soviet Union – 0.5 MW Capacity • China has developed several small Tidal Power projects and one large facility at Jiangxia and at mouth of Yalu.

17. CONCLUSION • Tidal Energy can be focused as an alternate source of Energy in Pakistan • Environmental impacts of Tidal process is much more smaller than using conventional fuels such as fossil fuels and nuclear plants etc. • Tidal Power alone cannot fulfills complete demand however can be helpful to overcome the problem of shortage.