Tidal resource is capable of producing clean, environmental-friendly and significantly affordable electricity on a large scale. It also has an advantage of being totally predictable, as tidal currents result from perfectly known astronomical phenomena. A desired level for exploitation of renewable energy resources has the potential to provide a solution to the present power crisis in Pakistan.
Energy generation based on renewable resources accounts for about one-fifth of the global power generation capacity. Global ocean energy resources are estimated to be over 32,000GW. It is important to note that the net potential of both wave and tidal power is greater than that of wind and solar, on a global perspective.
Tidal power stations are based on the idea of a windmill – a tidal energy unit functions like an underwater windmill. Electric power is transmitted through a sub-sea cable connected to the grid. A new installation method developed recently will reduce installation time significantly.
The first large-scale powerhouse, the Rance Tidal Power Plant of 240MW, was established in France in 1966. The world’s largest tidal power station, of installed capacity of 260MW, is currently located at Sihwa Lake in South Korea. The power station was completed in 2011 at a cost of $250 million, and has the availability rate of 98 percent. It is constructing a 1,320MW tidal power plant (to be commissioned by 2017), whereas another plant of 520MW is being planned.
China is turning its attention to tidal power, with one of its projects set to eclipse anything the world has seen in the sector so far. The Chinese are planning to construct a $30 billion tidal wall that could have an installed power base of about a gigawatt. The dam-like structure has turbines with curved blades that allow marine life to swim through while harnessing the energy in the water. The project has domestic and international backing, including from the Dutch government and eight Dutch companies. Plans of such dimension would enable China to surpass the UK, the current world leader in tidal power technology.Russia which currently operates a 1.7MW tidal power station, plans to construct three mega tidal power stations of 3,640MW, 8,000MW and 8,710MW capacities. Canada operates a 20MW power station.
UK currently operates a 1.2MW power station, and has constructed a 10.5MW plant. It now plans to establish a 300MW power generation facility. Scotland is the world leader in the commercial development of wave and tidal energy, having commenced power generation in November 2000. Meanwhile, a 2,200MW tidal power project is being developed in the Philippines. India is installing Asia’s first commercial-scale tidal power station off the coast of Gujarat.
Currently, Pakistan is confronted with energy crisis due to decline in conventional sources of energy. There is a large gap between demand and supply of electricity. The need for exploring alternative environmental-friendly and renewable energy resources has, therefore, become more important.
Tidal power is available at no fuel cost and minimal running cost. The net potential of both wave and tidal power in the universe is greater than that of wind and solar. If all suitable tidal sites in the world were exploited for tidal power, it’s estimated that 100 TWH of electricity could be produced each year.
Nevertheless, Pakistan has not yet come in this context, despite having different significant locations with high tidal current velocities or strong ocean currents along its 990km coastline. According to a study conducted by the National Institute of Oceanography, creek network in the Indus deltaic region, extending over 70km along the Arabian Sea, can alone generate 900MW tidal power.
Grid-based or off-grid tidal power stations could be constructed, depending on site conditions. In our case, off-grid power stations would be more advantageous for meeting rural needs of electricity. The coastline of Pakistan, which is about 1,045 km-long with dominant features, is the best resource for exploiting the tidal energy.
In Sindh, two sites, creek system of Indus delta of 170km and two to five metres tidal heights at the Korangi Creek, are available to exploit the tidal energy. Sonmiani and Kalamat are also commendable prospects of tidal energy in Balochistan.
Some see that tidal power plants in coastal creeks of Pakistan can remove the energy crisis to some level. The complex creeks network in the Indus Deltaic region, extending over an area of 170 kilometers along the 990-km coastline that Pakistan shares with the Arabian Sea can generate 900 megawatts (MW) of cheap energy, and sufficiently meet the power requirements of Karachi, according to a research conducted by the National Institute of Oceanography (NIO). A team of scientists, led by Dr G. S. Quraishee, a former director general of NIO, conducted the two-year study some 20 years ago, is not considered because Pakistani bureaucracy has a vested interest in producing energy through oil imports.
According to the NIO study entitled “Feasibility Studies for the extraction of energy from current and Halio Hydro Gravity along Pakistan Coast,” water flows with high velocity during floods and ebb tides, which is a “very favorable requirement” for the extraction of energy from currents. The power resources of the creeks system are great assets for future energy supply in the region.
The serious power shortage which the industry is facing at Karachi can be adequately met from these resources,” the study stated. Research carried out in “all the main creeks of Indus Delta,” namely Korangi Creek, Phitti Creek, Chan Waddo Creek, Khuddi Creek, Khai Creek, Paitiani Creek, Dabbo Creek, Bhuri Creek, Hajamaro Creek, Khobar Creek, Qalandri Creek, Kahr Creek, Bachiar Creek, Wari Creek and Kajhar Creek exhibit that,” about 900MW can be generated.
Korangi, Phitti and Chan Waddo creeks, all located near Karachi, “have good potential for power production and the estimated power available is 17,478 and 280MW respectively,” according to study. With the 20 million population of the vast city Karachi grumbling due to endless load-shedding, it is high time that the new governments pay attention to the conclusion of the study and bring some comfort to the distressed people.
In the latest scenario when developed countries are competing to tap into environment-friendly options of tidal energy, one wonders why tidal energy is not being exploited in Pakistan. There are many other new energy resources that could benefit Pakistan, such as ocean energy, including marine current power, osmotic power (from salinity gradients), ocean thermal energy, oceanogenic power (from surface waves), wave energy, and tidal power.
Construction of a 50MW power plant has been undertaken by India in the Gulf of Kutch. More plants are planned in India, as there is a potential of generating 8,000MW by exploiting tidal and wave energy. However, Pakistan has yet to move in this direction, despite having various strategic locations with high tidal current velocities or strong ocean currents along its 990km coastline. According to a study conducted by the National Institute of Oceanography, creek network in the Indus deltaic region, extending over 70km along the Arabian Sea, can alone generate 900MW tidal power.
A detailed study testing and assessing tidal energy across the coastline could show a huge potential for marine energy resources, which could be exploited for power generation on a commercial scale.
Exploiting renewable energy from the ocean is becoming increasingly important. One reason is that ocean energies are renewable and cannot deplete, the study said. The other is that, unlike solar or wind power, which manifests itself in kilowatts, ocean energies are being debated and planned, in some cases even executed, in terms of megawatts.
With the 15-million population of the mega city Karachi groaning due to persistent load-shedding, it is high time that the planners pay heed to the findings of the study and bring some solace to children who have to prepare for exams, the miserable people who need to sleep in order to perform efficiently at their workplaces the next day as well as housewives who have to perform household chores amidst stifling heat.
Research carried out in “all the main creeks of Indus Delta,” namely Korangi Creek, Phitti Creek, Chan Waddo Creek, Khuddi Creek, Khai Creek, Paitiani Creek, Dabbo Creek, Bhuri Creek, Hajamaro Creek, Khobar Creek, Qalandri Creek, Kahr Creek, Bachiar Creek, Wari Creek and Kajhar Creek showed that, “about 900MW can be produced.” Korangi, Phitti and Chan Waddo creeks, all located near Karachi, “have good potential for power production and the estimated power available is 174, 78 and 280MW respectively,” according to the study.
In the emerging scenario when developed countries are competing to exploit into environment-friendly options of tidal energy, one wonders why tidal energy is not being exploited in Pakistan.