Storm-resistant tech that generates electricity using seawater tested (msn.com)
Story by Ameya Paleja
• 11h
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A prototype of an innovative new technology called Ocean Thermal Energy Conversion (OTEC) is being built in Spain and promises a round-the-clock supply of renewable energy even in remote tropical islands that have conventionally relied on fossil fuels. When ready, the prototype will be deployed for a year-long test in the Canary Islands, Spain.
With the focus on switching to cleaner energy sources, countries are looking for innovative technology solutions that help them reduce carbon emissions and deliver energy security.
The abundantly available solar energy can work as an energy source even in the Alps, but only during the day. For energy demands through the night, the generated power must be stored in large batteries, which adds further costs to this transition.
Many companies have considered the sea waves a potential source of unlimited power. Interesting Engineering has also reported on technologies being used to harvest the power of the waves and how they can be brought onshore.
However, OTEC is a radically new approach to tapping into the ocean for energy. It is being built to brave storms as well.
What is OTEC?At the core of the OTEC technology is a turbine that needs to be moved to generate electricity. The innovation lies in how it moves the turbine using a working fluid.
It is well known that the surface of the seawater is warmer than the water in the depths. OTEC uses the heat from the seawater to vaporize a working fluid, which drives the turbine and generates electricity. The cooler water in the deep sea brings the working fluid to its liquid, and the cycle can be repeated.
The setup consists of three main parts: a cylindrical hull, a cold-water riser pipe, and a gimbal connection point. A scaled-down test in London last year confirmed the project’s technical feasibility, and now teams are building a 1:5 scaled prototype to be installed in the Canary Islands.
The facility near the Canary Islands where the OTEC device will be assembled before its installation. Image Credit: GlobalOTEC© Provided by Interesting Engineering
Built for tropical islandsThe floating energy generator is an ideal energy solution for tropical islands that have conventionally relied on fossil fuels for their energy needs. Renewable energy solutions such as wind and solar power require large tracts of land and favorable weather to maximize their output.
With changing environmental conditions, smaller island developing states (SIDS) are expected to be at the receiving end of extreme weather conditions such as storms, typhoons, and hurricanes. Offshore installation of solar and wind energy projects that can survive such harsh weather are still in their infancy and will take time to scale up.
On the other hand, OTEC is built with storm survivability in mind and can even be dismantled rapidly and carried onshore in extreme weather. When the event subsides, the setup can be connected back to resume energy generation.
Since seawater near tropical regions remains warm throughout the year and even at night, the system can be run round the clock, generating power 24/7.
“This prototype will provide us with the perfect opportunity test our cylindrical hull and gimbal solutions in 20m equivalent waves and hone our offshore connection and disconnection procedure allowing us to maximise asset lifetime and availability even in storm prone regions”, said Sam Johnston, Lead Engineer at Global OTEC, one of the partners of the project.
Other project partners are WavEC Offshore Renewables from Portugal, The Oceanic Platform of the Canary Islands PLOCAN in Spain (Spain), and the University of Plymouth in the UK. |
