Remotely controlled rescues for offshore wind

As offshore windfarms move into ever deeper and more remote waters, operators need to address the increased risks for potential man overboard and emergency evacuation situations. Could an Edinburgh-based autonomous search and rescue (SAR) start-up offer the solution?  

Offshore search and rescue services start-up Zelim has teamed up with Hampshire-based naval architect Chartwell Marine to deliver a remotely operated rescue vessel for the fast-growing offshore wind sector. The innovation comes as countries around the world, from Portugal to Japan, are seeking to accelerate offshore wind projects in response to the crisis in Ukraine, which has triggered price spikes and put fears about energy security firmly on the agenda. 

With the Global Wind Energy Council expecting 235 GW of new offshore wind capacity to be installed over the coming decade, seven times current capacity levels, there are growing concerns about how this rapid growth will be resourced from a personnel perspective. How will a rapidly recruited workforce be trained to cope with the demands of the hostile offshore environment?  The emergence of floating offshore wind, which will take operators into ever deeper and more remote waters, will only increase the hazards in the event of an accident, particularly one that involves an evacuation or man overboard (MOB) scenario. Such incidents may be rare but they are also potentially fatal, as seen last summer when four lives were lost at sea after the jack-up installation vessel Sheng Ping 001 capsized off Guangdong province in southern China while working on the 400 MW Huizhou Gangkou I wind farm. The remaining 61 crew were picked out of the water by rescue vessels and helicopters.  

Saving lives further offshore  

Incident data from G+, the global offshore wind health and safety organisation, has been trending down: in 2020 there were 743 reported incidents and injuries, of which 232 occurred on vessels and 241 in a turbine. Crew transport vessels (CTVs), which transfer personnel to and from offshore wind farms, were the main incident area in 2020, with 79 incidents, as well as being in the top three areas for the number of high potential incidents. As operations move further offshore, the risks only increase.  

This is where Zelim’s Survivor class search and rescue solution comes into play. The unmanned remotely controlled craft sits in a launch and recovery cradle attached to the wind turbine. In the event of a MOB incident, rather than waiting for deployment of a daughter craft from the in-field service operation vessel, the Survivor free falls 25 metres and its twin waterjets activate prior to contact with the water to stop the vessel drifting back towards the turbine. The craft is then remotely controlled by a pilot, who is located outside the offshore situation and using visual, thermal and GPS overlay and machine learning to find the MOB casualty.  

With no rescue personnel physically on board, a rescue conveyor system, rather like an upwards-moving travelator, is used to recover MOB casualties from the water. The unmanned rescue vessel doesn’t take the casualty ashore but rather acts as an accessible safe haven from the debilitating effects of cold-water immersion.  

Speed is of the essence in these situations, stresses company founder Sam Mayall, who speaks from bitter experience. A sailor, Mayall has lost friends at sea and has assisted in a number of emergency situations. “I wanted to be able to do things quicker and without risking rescue personnel,” he says when asked about the inspiration behind the Survivor. “It’s about saving lives without risking lives.” 

The air-conditioned cabin offers folding seating for 12 persons, plus space for two stretchers, along with easy-to-open door handles and a helicopter pick-up zone for evacuation to shore. 

On permanent standby 

This isn’t just a health and safety breakthrough. The technology not only ensures there are lifesaving vessels available on permanent standby operation, with no additional risk to personnel, but there are also significant cost savings and increased flexibility in operations and maintenance, which can account for 25-30 per cent of total lifecycle costs.   

And this will soon be put to the test. Construction on the first craft should start in July 2022, with first deployment in early 2023 in the North Sea. “It’s no longer a dream,” says Mayall. “We’ve done the tank testing, proven its operational in the field using prototypes and we’re now getting a huge amount of interest from different areas all over the world.” 

And there’s more innovation to come. In addition to the Survivor class, Zelim has also developed a smaller unmanned survival and rescue craft, the Guardian class, which can be launched from a ship in the role of a fast rescue craft.  

Amy McLellan is a journalist and author. She was previously editor of Energy Day. Twitter  @AmyMcLellan2