Zero-carbon pioneering vessel takes centre stage in New York for Earth Day

Innovative technologies on board

Sustainability lies at the heart of Energy Observer’s design. It was one of the first vessels to integrate a mix of renewable energies with onboard hydrogen generation and storage. Since 2019, Energy Observer has employed two first-of-its-kind automatic wind turbine OceanWings, measuring 32 m², contributing to 30% of the vessel’s propulsion. The wings allow the boat to reach 12 knots without impacting its electricity consumption. The hybrid-powered vessel is fitted with two electric motors that drive variable propellers.

Hydrogen is produced on board by seawater electrolysis for the vessel’s hydrogen fuel cell. Based on a Proton Onsite system specially converted by Energy Observer’s engineers, the onboard electrolyser can produce up to 8 kg of green hydrogen per day and generated more than 300 kg in 2023. Because of its electric consumption, electrolysis is done dockside, though it is possible to electrolyse while underway once the OceanWings provide enough thrust to keep the vessel moving. Currently, 62 kg of hydrogen is stored on board, providing 1 MWh of electricity and 1 MWh of heat. Since it began sailing, Energy Observer has produced over 1.3 tonnes of hydrogen on board.

The vessel’s Energy Observer Developments (EODev) marine hydrogen system is designed around a Toyota hydrogen fuel cell, which powers the onboard electrical production system, operating at a power of 70 kW. Designed ad-hoc to operate on a boat, the cooling system features a temperature exchanger able to withstand moisture and salinity. Toyota and EODev are utilising Energy Observer as a floating lab to test and optimise the lifespan and reliability of this system and to predict maintenance for their other units in operation. 

Energy Observer has two means of energy storage, with 106 kWh of li-ion batteries for short-term storage, and hydrogen produced from seawater and stored in gaseous form (350 bars) on board for long-term storage in eight hydrogen fuel tanks. If the vessel had to store its energy in batteries alone, it would weigh twice as much, according to the operator. The whole system emits no CO2 or fine particles.

To capture solar power, the vessel’s side wings are fitted with 202 m² of bifacial photovoltaic panels, which generate a peak power of 34 kWh. The bifacial photovoltaic panels developed by the Institut National de l’Energie Solaire on the vessel’s side wings and aft section were installed in 2016-2017. Many of these panels, especially forward of the aft wings, have suffered material damage after being slammed into by powerful waves during the passage across the Pacific. As a result, a dip in overall efficiency was observed with these bifacial panels and some have had to be replaced. Some panels have also suffered water ingress in their encapsulation, again due to the waves washing over the decks during sea passages in some very rough weather and heavy seas.

The flexible solar panels all over the vessel form part of a very active partnership with Italian manufacturer Solbian. Innovations in terms of polymers, adhesives and contactors are all tested aboard the vessel, which means their performance is closely followed using monitoring software developed aboard the boat.

Energy Observer’s desalination system has gone through a substantial overhaul, but it is now capable of supplying the crew with fresh water and, above all, high-quality deionised water for the electrolyser.