Global OTEC awarded an Approval in Principle for a Barge to support its Floating Ocean Thermal Energy Conversion system

LR and Global OTEC teams

Global OTEC has been granted Approval in Principle (AiP) by Lloyd’s Register (LR) for a barge to support the world’s first-of-a-kind floating Ocean Thermal Energy Conversion (OTEC) system. The 1.5MW floating unit named Dominique, is being designed by Global OTEC and set to be installed in São Tomé and Príncipe in 2025.  

The project illustrates a pioneering example where diesel fuel imports can be replaced with clean, baseload energy from the ocean. The OTEC operating principle involves an offshore system that uses warm surface seawater to evaporate a low boiling point liquid. The hot vapour produced drives a turbine that produces electrical power. Cold water from the deep ocean is then used to cool the vapour and condense it back into a liquid so the cycle can repeat itself all year round to produce electricity with zero CO2 emissions. 

The LR AiP process provides technology developers with early confidence that their technology is capable of being appraised against existing codes and standards. The award of the AiP, acknowledges that the Global OTEC’s technology barge can meet the necessary requirements for providing a structural basis for the OTEC technology. 

Building on the certificate of approval issued from marine warranty surveyor, ABL Group, we have further validation of our technically sound and reasonable approach to commercialising OTEC technology. The challenges which have stalled OTEC deployments are not insurmountable. Following excellent engineering practices, overseen by regulatory bodies, provides our customers and investors with a great deal of comfort”, highlights Global OTEC Founder and CEO Dan Grech. 

In awarding the AiP to Global OTEC, Jenny Wilson, Engineering Discipline Team Manager at Lloyd’s Register said “LR is pleased to award an Approval in Principle to Global OTEC for a barge to support its Ocean Thermal Energy Conversion platform, Dominique. This project fits squarely within the UN sustainable development goals of the IECRE system that LR as a Renewable Energy Certification Body (RECB) for Marine Energy fully supports. Global OTEC’s platform will offer a green alternative to fossil fuel energy with zero carbon emissions and will be a vital source of renewable electricity for developing countries.

OTEC cycle (reprinted from IEC TS 62600-20, 2018)

Certificate of Approval

In April 2023, Global OTEC already achieved its first Certificate of Approval for the methodology of installation of a Cold-Water Riser, for the purposes of an offshore OTEC platform. This was a crucial step in the design process, using standards already tested and applied to the Oil and Gas industry for implementation in OTEC deployments. The certificate was issued by the Marine Warranty Surveyor company ABL Group and has been in effect since the 4th of April. This approval was particularly important given the technical challenges faced by OTEC installations, and the long history of OTEC’s unsuccessful implementations.

About Global OTEC

Global OTEC is a UK-based private company set up to accelerate the commercialisation of a floating OTEC technology to develop zero-carbon, baseload, clean energy sources that achieve maximum impact in empowering Small Island Developing States (SIDS), Least Developing Countries (LDCs) and Coastal Nations  with energy security whilst helping the Earth reduce greenhouse gas emissions and eventually eliminate total dependence on fossil fuel.

About Lloyd’s Register 

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