At Apollo, we’ve supported a wide mix of offshore renewables projects – not just the mainstream, but also the first-of-a-kind including;
- Tidal turbines
- Novel Wave generators
- Offshore multiconnection substations
- Subsea batteries
- Floating foundation
These are the sorts of projects that come with plenty of unknowns. They often don’t have big budgets or ready-made codes. But they do offer the kind of technical challenge we enjoy.
Below are a few examples, shared by one of our engineers during a recent lunch and learn. They’re varied, sometimes messy and always full of learning.
Predictable generation, unpredictable loads
Project: MeyGen Tidal Turbines – Atlantis AR1500, Andritz Hammerfest AH1000 MkI
Apollo was involved in the design of the stab connector — a critical mechanical interface for tidal turbines in high-flow environments. We developed a bespoke fatigue analysis workflow, using ANSYS and custom scripts to handle complex, multi-axial, non-linear loading. The design balance ease of installation with fatigue resilience, using clever design. Material selection was also critical with cast steel, Inconel cladding and wear resistant composite pads.
Scaling floating wind
Project: 15MW Floating Foundation (Pre-FEED)
This tension-leg platform was a step up in scale, and a chance to refine our approach to floating structures. Working from OrcaFlex load data, we used static ULS load cases and full-substructure ANSYS models to understand joint behaviour, connection design, and the need for additional stiffening. Closely working the 3D Autodesk Inventor modelling with the Ansys FEA analysis helped us iterate quickly and optimise the design.
Design for reality
Project: Bombora mWave
A membrane-based wave energy converter, seated on a 75m-long subsea structure. We provided the structural design and tackled challenges around buoyancy, wave-induced loads, and modular assembly. Fabrication yard limits meant bolted connections, which complicated installation plans.
Combining wind and wave
Project: Hybrid Floating Substructure
A concrete foundation intended to host both wind and wave energy devices. Apollo modelled motion response using AQWA and carried out FEA to identify rebar and bracing needs. We also ran sensitivity checks on draft depth and waterplane area, which highlighted new dynamic behaviours and informed mooring recommendations.
Keeping it grounded underwater
Project: Minesto – Subsea Tether for Underwater Kites
Minesto’s kite-based tidal system flies in figure-of-eight patterns to generate power. We helped assess fatigue on the tether pile — a cast-in-place seabed anchor — using simplified analysis informed by first principles and practical assumptions. Despite limited historical data, the work offered a solid foundation for future iterations.
Subsea energy storage
Project: Verlume Battery Foundation
Verlume’s seabed-based battery storage required stability assessment in storm conditions. Apollo applied CFD to evaluate drag loading, seabed shear, and sediment transport. This allowed for optimisation of ballast, improving design efficiency and avoiding over-conservative assumptions. A nice example of oil and gas expertise transferring into renewables.
Looking back, thinking ahead
Project: Tidal Turbine Test Platform – Life Extension in Orkney
This ageing structure, used for turbine testing at EMEC, needed inspection to assess whether it still had a role to play. Apollo managed diver operations, topside inspections, and fatigue assessment using ANSYS. Strong currents and short dive windows limited the inspection scope — but we provided a pragmatic view of remaining life and safety considerations. A change of ownership meant the available design and operational data was very limited, something we are very used to dealing with in ageing oil and gas facilities.
Making connections count
Project: PALM QCS (Quick Connection System)
Apollo’s PALM Quick Connection System supports rapid subsea mating of electrical and mechanical components. We carried out lab-scale and full-scale testing in Orkney, validating performance under real sea conditions. We also assessed extreme pitch behaviour during a 10-year return-period storm – with actual results confirming the conservative nature of the initial model.
Flexible power, shared platforms
Project: Celtic Sea Multi-Use Substation
We’ve performed design for substations that could connect multiple offshore projects. It’s a multi-disciplinary challenge — structural, electrical, technical safety — and constantly evolving. We used everything from hand calcs to automated jacket optimisation tools, adapting as project developed.
Developed for the Pembrokeshire Demonstration Zone, this offshore substation design had to be modular, scalable, and compatible with both commercial wind farms down to wave demonstrator connections. We used ANSYS and response surface optimisation tools to refine the jacket structure. The number and layout of J-tubes turned out to be a key design driver — something we wouldn’t typically see on a standard oil and gas platform.
Summary
There are common themes around these projects requiring the transferring of knowledge and techniques used in existing technology and applying it in a new way for the novel designs. Being able to think out of the box but ensure the resulting designs are robust and safe requires the extensive experience we have developed in offshore engineering.
These projects are rarely straightforward. They require careful assumptions, close collaboration, and a willingness to adapt. But they’re the kind of work that keeps things interesting — and the kind of work we think is worth doing.
If you’d like to know more about how we approach engineering for emerging renewables, or if you’re curious about joining our team, we’d love to hear from you.
Hear more about our projects
To hear more about these projects you can sign up to the Ansys’ Digital Solutions for the Energy Industry on 29-30 April 2025 where Gary Clark will be presenting. The virtual event explores is driving innovation and efficiency in the energy (Green, Renewable, Oil & Gas) and industrial sectors, register here.
Can’t make it? Get in touch renewables@apollo.engineer
This is the kind of work we love to do
If you’re the kind of person who thrives on solving the unknown — we’d like to hear from you.
See careers at Apollo.