Offshore platform that converts ocean temperature differences into electricity

Project stakeholders

The PLOTEC project is driven by a European consortium led by Global OTEC, a company specialized in the development of ocean energy solutions based on OTEC technology. The consortium also includes Cleantech Engineering Limited, WavEC Offshore Renewables, PLOCAN —the Oceanic Platform of the Canary Islands—, Quality Culture, AGRU Kunststofftechnik and the University of Plymouth School of Engineering, Computing and Mathematics. The project is funded by the Horizon Europe programme and UK Research and Innovation, with a total budget of €3.5 million.

Project description

PLOTEC is developing a floating offshore platform to demonstrate the potential of OTEC —Ocean Thermal Energy Conversion— technology in real-world environments. This technology generates electricity by harnessing the temperature difference between warm surface water and cold deep seawater. Through a thermodynamic cycle, this thermal gradient makes it possible to produce energy continuously, unlike other variable renewable sources such as wind or solar.

The main innovative element is not OTEC technology itself, which is already known and has previously been demonstrated at small scale in onshore facilities, but rather the development of a specific offshore platform to make it scalable. Onshore solutions depend on large pipes to capture deep seawater, which limits their technical and economic viability. The offshore proposal reduces the required pipe length by up to 80% compared to land-based systems, facilitating deployment on tropical islands and coastal areas with nearby access to deep waters.

The prototype, called Don, has been installed at PLOCAN’s test site off the coast of Gran Canaria. The infrastructure includes a cylindrical hull, a cold-water intake pipe and a specific connection point. The installation of the seawater intake system has been one of the project’s most relevant technical milestones, as this element is key to validating the operation of an offshore OTEC platform under real conditions.

The project places particular emphasis on climate resilience. The platform is designed to withstand the extreme conditions typical of tropical oceans, including storms, hurricanes and cyclones. For this reason, PLOTEC has direct applicability for islands and tropical territories that mainly depend on diesel or fuel oil generators to produce electricity, facing high energy costs and exposure to fossil fuel price volatility.

The energy generated by this type of system is mainly intended to provide baseload electricity to island communities, strengthening energy security and reducing dependence on imported fuels. In addition, the validation of the prototype can generate knowledge applicable to other offshore marine technologies, especially in structural design, materials, computational modelling and floating systems.

Project objectives

The main objective of this innovation case is to contribute to the energy transition of island territories vulnerable to climate change, offering a renewable energy alternative capable of producing electricity 24/7 at sea. In the field of the blue economy, the case is relevant because it combines marine energy, offshore engineering and climate resilience, with the potential to open up new opportunities.

The project also aims to demonstrate that OTEC technology can operate in offshore environments in a reliable, resilient and economically viable way. It seeks to validate new designs and materials for floating platforms, reduce technical barriers associated with deep-water intake and move towards a scalable model of continuous renewable energy generation.

Publication date

May 15th  2026.

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