India is taking its first steps for development of tidal or offshore energy. Though this space has immense potential, a few chinks need to be ironed out before whole-scale adoption and deployment of this technology.
India is blessed with a coastline that´s around 7,600 kilometers long. But despite the immense potential offered by this form of tidal energy, the country has still not managed to tap into this seemingly inexhaustible source of power.
Globally, players are beginning to understand the true potential of this sector. For example, a latest study by the Electric Power Research Institute (EPRI) estimates that the potential wave energy resource along the US coastline is at 1,170 terawatt-hours per year, enough to supply half the United States´ annual electricity demand. In fact, the study goes on to state that tidal energy, once the infrastructure is in place, can become a reliable, steady and dependable power source, even cheaper than wind power.
But tidal power technology is still in its infancy, and governments around the world are trying to offer incentives to players in this segment for new initiatives. For example, the EU has recently offered financial incentives for development of tidal power components. Marine energy companies Minesto and Atlantis Resources Ltd have been awarded financial packages from the Eurostars Programme, funded by the European Union. The funding is awarded to a project that aims to reduce the cost of tidal energy and is a unique collaboration between two different marine energy developers on the global arena. According to a statement by Atlantis Tim Cornelius : ¨Constant innovation and collaboration in the development of tidal turbines will be critical to the commercialisation of the industry globally. This funding and consequent partnership will enable us to design and build even better turbines, capable of operating at even greater efficiency in the most hostile of environments.¨ Minesto had earlier signed a Memorandum of Understanding (MoU) with Florida Atlantic University, to examine the technical, environmental and economic feasibility to install demonstration and commercial power plants in the Florida current. The company said in a release that ocean current power is a renewable and unexplored energy source. Explaining why ocean current energy can be a reliable, non-intermittent, renewable energy resource that can supply base grid power (while matching the reliability of nuclear, gas and coal power), the company said that the currents exist in open oceans and they flow predominantly in the same direction. Tidal power can hence be a potential stable and reliable energy source. The British Department of Energy and Climate Change (DECC) has also been funding research in the tidal energy sector, to unlock the low velocity tidal current market in the UK.
India is taking its first steps to build a tidal power plant. According to the Ministry of New and Renewable Energy, the Gulf of Cambay and the Gulf of Kutch in Gujarat on the west coast have the maximum tidal range of 11 m and 8 m with average tidal range of 6.77 m and 5.23 m respectively. The Ganges Delta in the Sundarbans is approximately 5m with an average tidal range of 2.97m. The Ministry says that it has identified economic power potential of the order of 8,000 MW with about 7000 MW in the Gulf of Cambay, about 1,200 MW in the Gulf of Kutch and about 100 MW in the Gangetic Delta in the Sunderbans region in West Bengal. MNRE had earlier 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, but the project failed to see the light of day due to financial constraints. Way back in 2012, the Gujarat government had indicated that it might again look at tapping the tidal power potential in the State, by issuing a notification that claimed that it would be possible to ¨produce tidal wave power at two spots - in the Gulf of Kutch near Mandva, and in the Gulf of Khambhat near Hazira.¨
The Government Resolution said that the National Institute of Oceanography, Goa, has been asked to carry out marine environment impact assessment for tidal wave power.
It remains to be seen if the government will look at developing tidal energy this year as part of its thrust to boost renewable energy production and meet its ´Power for all´ objective. ¨We must move fast to grab India´s legitimate share in the emerging ocean-based industries, which include off-shore wind, tidal and wave energy,¨ Harsh Vardhan, Minister for Science, Technology and Earth Sciences said in a recent statement.
Meanwhile, a number of countries around the world are stepping on the gas as far as tidal power is concerned.
The construction of the world´s largest tidal stream turbine power plant is set to begin in February. The facility will consist of 269 turbines, installed on the seabed of north-east Scotland. It will have a total capacity of almost 400 MW once completed. Japan has selected IHI Corp and Toshiba to develop an underwater tidal energy turbine system. As an island nation, Japan is looking at tidal power in a big way, with the county´s New Energy and Industrial Technology Development Organization (NEDO) promoting R&D projects in ocean energy power generation technologies since FY2011, with the goal of developing world-leading technology and contributing to lower CO2 emissions. The unique ¨underwater floating type ocean current turbine system¨ developed by IHI and Toshiba will demonstrate power generation in a real ocean environment, in a project expected to continue until FY2017. The research work is expected to prove the viability of ocean energy power generation and create the framework for the fledging tidal power industry.
The Perpetuus Tidal Energy Centre (PTEC) is coming up off the Isle of Wright, which will provide the world´s first grid-connected tidal array test facility. Construction is expected to begin only in 2017.
The Road Ahead
Recent research indicates that power from wave energy might be easier to integrate into a national grid, due to the comparative consistency of wave power across different installations. Short-term generation capacity of tidal power can also be accurately predicted as compared to other sources of wind energy. Tidal energy is not intermittent in nature, as waves keep rolling (with almost uniform strength) 24/7 and 365 days a year.
But tidal energy technology, as stated earlier, is still in its infancy. For example, many generators used in tidal power generation get corroded rapidly due to the saline water and constant battering of waves. There are also concerns that marine life might be affected if large-scale deployments of tidal energy installations take place. Siemens said at the end of last year that it would abandon its ocean power generation business and divest Marine Current Turbines, the Bristol-based tidal turbine development company it had acquired in 2010. Scottish wave energy company Pelamis Wave Power has gone bankrupt after it failed to secure developmental funding. Edinburgh-based developer Aquamarine Power is retrenching all but its core staff.
Ergo, lack of funding seems to be the biggest bottleneck for the tidal power industry. India would do well to wait and watch and look at investing in this renewable energy source as technologies develop and become more standardised. Nobody doubts the potential of this important energy source... but tidal energy has some way to go before maturity and large-scale deployment.
- Devarajan Mahadevan