Monaco is extending its environmental ambitions beyond the world of superyachts, with the Yacht Club de Monaco expanding its SEA Index certification to include smaller recreational vessels.
The CO₂ assessment system can now be applied to boats from ten metres in length, including production models and catamarans. Developed with maritime classification specialist Lloyd’s Register, the expanded method covers different designs ranging from displacement and planing monohulls to production catamarans measuring up to 35 metres.
Until now, the SEA Index has primarily been associated with larger yachts. More than 130 vessels over 24 metres have already been certified, but the latest expansion brings a much broader section of the boating community into Monaco’s environmental programme.
Crucially, vessels will not be measured against one sweeping standard. The system compares boats according to characteristics including hull design, speed and typical operating profile, providing a more realistic picture of their environmental performance.
This should give owners and prospective buyers clearer information when comparing emissions. It may also help shipyards consider efficiency earlier in the design process, rather than treating sustainability as an attractive—and occasionally rather shiny—afterthought.
The results could extend beyond the vessels themselves. Marinas, ports, insurers and financial institutions will be able to use more consistent environmental criteria when assessing a wider range of boats.
The certification forms part of the wider Monaco, Capital of Advanced Yachting initiative. Its network already connects 25 marinas across the Mediterranean, Seychelles and Saint-Barthélemy, alongside 87 members of the Japan Marina and Beach Association.
Monaco has long occupied a prominent place in international yachting. The more difficult task is ensuring that influence is used to improve the industry rather than simply admire it from the harbour.
By opening the SEA Index to smaller boats, the Principality is helping make environmental accountability more accessible—and signalling that cleaner navigation should not be reserved solely for the largest vessels at sea.