Remember the Solar Sailor ferry with its tilting solar wings? Its inventor Robert Dane took that idea out to the open ocean. His company, renamed Ocius Technology in 2014, builds Bluebottle: an uncrewed surface vessel designed to stay at sea for very long periods on renewable energy alone.
Each Bluebottle is about 7.4 m long with a fibreglass hull. Its signature feature is a rigid solar sail: a tall panel covered in solar cells that generates electricity in the sun and acts as a sail in the wind. It also harvests wave energy to help it along. A hybrid version adds a small generator for long periods of low light.
Because it never needs refuelling or a crew, Bluebottle can watch huge areas of ocean, carrying sensors such as radar, cameras and underwater acoustic arrays. It is used by the Royal Australian Navy and the Royal New Zealand Navy. In March 2026 Ocius won a contract to build 40 more for Australia.
From a harbour ferry to a self-sufficient ocean robot, the “solar wing” has come a long way.
Technical data
| Builder | Ocius Technology, Sydney (formerly Solar Sailor), CEO Robert Dane |
|---|---|
| Type | Uncrewed surface vessel (ocean drone) |
| Length | ~7.4 m, fibreglass hull |
| Energy | Rigid solar sail (solar + wind) plus wave energy; optional hybrid generator |
| Payload | Radar, electro-optical/infrared cameras, towed acoustic array |
| Users | Royal Australian Navy, Royal New Zealand Navy |
Photo: CB Researcher / Wikimedia Commons, CC0
Sources: Wikipedia: Ocius Technology