SUBSEA TECHNOLOGY POWERSURGE SUBSEA


Stefan Marx and Sören Johannsen delve into the world of subsea energy storage


I


n the ever-evolving realm of underwater technology, German firm SubCtech stands out with its innovative approach to


ocean monitoring and subsea power solutions. Guided by the expertise of founder and CEO Stefan Marx and COO Sören Johannsen, the company has carved out a significant niche in this highly specialised industry. Both here discuss SubCtech’s products, the challenges of subsea engineering and the sustainability of modern subsea energy storage. Based in Kiel, Germany, SubCtech


has two primary business units: Ocean Monitoring and Ocean Power. The company began by manufacturing products to monitor seawater quality, and, over time, its focus has evolved to meet the increasing demand for battery power underwater. From its small beginnings, crafting


small underwater batteries, the firm now boasts a 1MWh battery storage system set to be in operational use from the beginning of 2024. SubCtech’s Ocean Power unit


manufactures subsea batteries that can be deployed aboard underwater vehicles or as backups for oil and gas industry applications offshore. To ensure its customers are comprehensively serviced, the Ocean Power unit is subdivided into three sectors: offshore energy, underwater vehicles, and standard subsea power products. Founder and CEO Stefan Marx says


SubCtech’s Ocean Power unit offers both standard batteries and bespoke solutions: “We offer solutions that fit into the customer’s available space and within its weight limitations – that’s where our roots lie, and that’s the service that has delivered our growth thus far.”


44 www.engineerlive.com


A BOOST IN STORAGE The company’s engineering prowess was on full display in late 2023, with SubCtech’s unveiling of the largest battery that it has ever produced: a 1MWh battery storage system. The battery is the first subsea


MWh battery in the world. But it is also only one among many other batteries in SubCtech’s collection including two perennial off-the-shelf battery solutions dubbed ‘Big Jim’ and ‘Long John’. Both battery units have standard physical dimensions and similar weights, but the innards can be customised according to specific requirements, such as capacity and voltage, both within set limitations. For vehicle-based solutions,


SubCtech offers three different standard battery housing diameters, namely 260mm, 310mm and 416mm internal diameter sizes. Meanwhile bespoke sizes, energy, power, and voltage ranges are available on request.


QUALITY GERMAN ENGINEERING SubCtech was founded in 2010 by Marx, who boasts over 30 years’ experience working in ocean-related industries in various roles. The company was originally headquartered in a small town near Kiel, but soon moved into Kiel, where its staff-count has gradually risen from 20 to 80 to accommodate growing demand for the company’s products. Following several relocations around


the city to accommodate its growing workforce and workload, SubCtech constructed its own production space. SubCtech’s products are qualified


according to military standards, and all are certified by Det Norske Veritas (DNV), an internationally accredited


registrar and classification society headquartered in Norway. This DNV certification, which seeks to guarantee the safeguarding of life, property and the environment, ensures comfort for users of the company’s products and is a legal qualification for any equipment fitted to the deck of a vessel.


THE IMPORTANCE OF MATERIALS SubCtech sources the highest- quality raw materials from around the world for the construction of its products, an important point about the company. “The steps from prototyping to operational use for any material and any product is a long process involving testing and certifications,” says COO Sören Johannsen. “There’s a big difference with the quality of materials used underwater and our task is to sell a fully qualified, 100%-secure product.” One material is titanium used for


every battery’s pressure hull – most of the battery’s internal components are manufactured at SubCtech including battery management systems, hardware, software, testing, control systems. “While we’d prefer to use existing


materials, so many components our products need for deep-sea operations simply aren’t available on the market, and so we have to make them ourselves,” Marx says. The same applies to its production


machinery and even test-bed equipment, all of which is developed and built in-house since it simply doesn’t exist in the market. Mercifully, then, one of the most


important components – lithium battery cells – are sourced from well-known producers with whom SubCtech has supply contracts.


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36  |  Page 37  |  Page 38  |  Page 39  |  Page 40  |  Page 41  |  Page 42  |  Page 43  |  Page 44  |  Page 45  |  Page 46  |  Page 47  |  Page 48  |  Page 49  |  Page 50  |  Page 51  |  Page 52