Imagine a wave energy converter that behaves more like a living organism than a machine: flexible, tuneable, self‑sensing, and capable of healing itself. This vision has been at the heart of Wave Energy Scotland’s (WES) Direct Generation (DG) programme, which has spent the past several years exploring a new class of soft electrostatic materials that produce electricity as they stretch and flex. These technologies offer a fundamentally different pathway from traditional wave energy systems, replacing heavy mechanical components with lightweight, scalable cellular architectures.

This opportunity mirrors other major breakthroughs in clean energy. Solar energy reached global dominance through scaling individual modular units to form large arrays. Direct Generation has the potential to unlock a similar leap for wave energy, by using modular metamaterials instead of monolithic machines.

Over the past two years, the DG programme has brought together technology developers, researchers, and industry leaders to investigate this emerging space in detail. The newly released Direct Generation Final Report captures the findings from this work, covering the scientific foundations, programme activities, technology outcomes, and a roadmap toward commercialisation. It serves both as a resource for researchers looking to advance these technologies and as guidance for policymakers considering where future funding and innovation efforts should focus.

What technologies were investigated?

Two technologies – Dielectric Elastomer Generators (DEGs) and Dielectric Fluid Generators (DFGs) – were investigated as part of the programme. Both operate on the principle of variable capacitance, where electrical energy is harvested as capacitance changes during wave excitation. However, they achieve this through different physical mechanisms. DEGs are driven by material stretch: flexible elastomer membranes coated with electrodes deform under wave loading, changing their capacitance as they stretch and relax. In contrast, DFGs are driven by fluid displacement: dielectric fluid moves between interconnected cells, causing each cell to “zip” closed or open depending on external pressure, which in turn alters electrode separation and capacitance.

How were these technologies investigated?

The programme was structured around three complementary strands:

1.       A concept design competition to stimulate innovative ideas and explore novel DG-enabled WEC architectures, broken down into two rounds:

·       Round 1 involved five teams working intensively over 14 weeks to generate early design concepts, understand systematic benefits and identify research requirements.

·       Round 2 down-selected two teams (4c Engineering and TTI Marine Renewables) for a deeper nine-month investigation, including technical assessments, manufacturing/material identification, and prototype development.

2.       Targeted research projects to deliver the enabling R&D required for materials, metamaterials, and electro-mechanical characterisation.

·       Origami structures were investigated for DFG cell architectures by the University of Oxford and Plymouth as part of a FlexFund Project.

·       Stretchable electrodes for DEG integration were investigated by the University of Manchester as part of a FlexFund Project.

·       Electro-mechanical fatigue for DEG/DFG materials investigated through an EPSRC-funded PhD by Swansea University.

3.       External stakeholder engagement with industry leaders, including SBM Offshore and Wacker Chemie AG, to support knowledge exchange and understand real world manufacturing and deployment considerations.

What were the outcomes of the programme?

The Direct Generation programme uncovered a range of systematic insights through concept development. Across the designs explored, several consistent advantages emerged: (1) lightweight, morphable structures that flex and move naturally with the ocean environment, (2) distributed power generation embedded throughout the device rather than concentrated in a single subsystem, and (3) modularity with inherent redundancy.

When comparing DEGs and DFGs, DEGs emerged as the maturer option, with clearer performance limits and an improved integration path into wave energy devices. DFGs, while earlier in development, showed promising advantages, especially around durability, thanks to their ability to decouple material deformation and rely on fluid movement instead.

Across both technologies, performance was assessed against five core metrics: power density, longevity, manufacturability, sustainability, and cost of energy. A key insight emerged: power density and longevity are strongly interdependent. Achieving longer lifetimes results in large reductions in energy output, which may necessitate a different economic model compared with conventional offshore structures – one where low-cost modules are routinely replaced and recycled as part of normal operations, similar to consumables in other industries. On the manufacturing side, the programme found a clear route toward scalable processes, with roll-to-roll techniques, spray-coated electrodes, and other methods borrowed from the flexible electronics industry offering potential for mass production.

To focus future research, three factors were identified as the main drivers of levelised cost of energy (LCOE) for DG systems, along with guidance values which should be targeted:

·       Power density: ≥ 40 W/kg

·       Longevity: ≥ 7-year module life

·       Metamaterial cost: ≤ £50/kg

Meeting these targets will require sustained progress across materials science, cell and module architecture, power electronics, scalable manufacturing, and system integration. Yet despite the challenges, the programme’s findings show that Direct Generation remains a credible and genuinely innovative pathway for future wave energy systems. The report outlines clear research priorities and identifies the stakeholders best placed to advance them.

Progress will likely follow a staged development pathway, starting with support from the wider electroactive polymer community and early stepping-stone applications in sectors such as sensors and soft robotics. These areas provide valuable opportunities to mature electroactive materials and module designs before moving toward larger marine demonstrators. Due to the inherent simplicity and modularity of DG architectures, early deployments at small scales can deliver meaningful operational learning that directly informs the design of later, utility-scale systems.

In the long term, the scale-up journey for Direct Generation may mirror that of solar energy, where performance improvements, cost reductions, and widespread adoption were achieved not through building bigger machines, but by replicating large numbers of identical, low-cost units into progressively larger arrays – a pathway which Direct Generation could seek to emulate.

For more information on the Direct Generation programme, please refer to Direct Generation Final Report here.