by Arvind Ahuja, Zara Maritime
Look around and you will see movement everywhere, whether it is man-made machines viz. cars, escalators or natural viz. people walking, the trees swaying, flags fluttering in the wind or the beautiful soft motion of the sea waves.
When you think about it, it is ultimately some form of energy which is moving the cars and the trees and the seas. When the natural energy, which is allegedly abundant, is tapped or extracted, and converted into another usable form, it is called renewable energy.
Hydro-Electric power generated by using water from dams to drive electric turbines has been used for decades, so extracting energy from water is not exactly new. But obtaining large amounts of energy from sea-water at a viable capital cost and keeping the project commercially cost effective throughout its life cycle is a relatively new challenge.
Wind turbine farms on floating platforms at sea, remain forms of wind energy and cannot be termed as power from marine sources.
Globally, research and development has been mainly in:
- Wave energy converters which need significant wave height
- Tidal turbines which need to be placed in coastal areas
- In-stream turbines require fast moving water in rivers or canals
- Ocean current turbines require strong marine currents
- Ocean Thermal energy converters require deep tropical waters to use the temperature difference of hot water at the surface and the freezing cold water at seabed depths to drive heat engines.
The limitations of the equipment being tested so far, are that they require strong currents, high swell or long amplitude waves, which are available only in a limited number of geographical locations.
The main challenges are that the equipment itself is expensive to produce, deploy and maintain and in many cases must occupy very large areas to generate sufficient power even for a few homes, must be friendly to aquatic life forms and has to be placed in areas away from navigable waters.
The seas surrounding UAE have a swell of more than 2 meters, especially in early evening till late night, and the thermal changes offer an excellent opportunity to researchers to explore and develop area specific technologies and equipment for tapping into this renewable energy source in the UAE.
Further research is being conducted to generate electricity by using the sea’s salinity and to generate hydrogen from sea water to power hydrogen cell technology.
The biggest advantage of the country presents the biggest challenge in using existing marine renewable energy technologies, as the U.A.E. is a maritime nation and even though there is a vast coastline, nearly all of it is navigable.