Marine Welfare Technology
High-Performance Bubble Curtain For Offshore Wind Piling
Pulcea brings together expertise from naval research, oil and gas, aquaculture and marine engineering to create a high-performance bubble curtain for underwater noise abatement during offshore wind installation.
Traditional bubble curtains compress air and force it down to the required depth where it is released and rises back to the surface. Pulcea generates fine-scale, neutrally buoyant, oxygen bubbles at various depths and contains them close to the noise source. These different technologies deliver different benefits and can be complementary to each other.
Pulcea’s novel acoustic principle has been demonstrated via controlled testing and independent verification. Development is now focused on validation at a scale relevant to offshore operational deployments.
The offshore wind noise challenge
Sound is fundamental to life underwater. Marine mammals such as the harbour porpoise rely on it to communicate, navigate and locate prey.
High levels of underwater noise can cause disturbance and, at sufficient levels, there is a risk of auditory injury, potentially affecting these essential behaviours.
Effective noise abatement can help reduce these impacts while supporting the continued development of offshore wind.
As offshore wind is scaling rapidly, with larger turbines, deeper waters and increasingly demanding installation programmes, managing underwater noise during installation is an important part of protecting the marine environment and supporting the development required to combat climate change.
The Offshore Wind Industry Council (OWIC) recognises underwater noise as an important environmental and consenting challenge and is working with industry and government to support effective, proportionate approaches to noise management.
The challenge is to deliver effective noise abatement that works in real offshore conditions on a commercial scale.
A different kind of acoustic barrier
Pulcea brings together established principles of physics, chemistry and bubble acoustics, applying them in a new way to underwater noise abatement for offshore wind.
The technology uses a very low concentration of hydrogen peroxide (H2O2), a compound that occurs naturally in the marine environment and breaks down to water and oxygen.
This generates fine-scale oxygen bubbles within a controlled barrier fluid contained around the monopile during installation. A small amount can create a disproportionately large physical effect, generating around 600 times its volume within the barrier fluid.
The bubbles are maintained within the fluid, creating a stable mixture of liquid and gas with different acoustic properties from the surrounding seawater. Close to the noise source, this forms a high performance acoustic barrier that reduces the transmission of underwater sound.
Unlike conventional bubble curtains which release compressed air into open waters, Pulcea maintains fine-scale oxygen bubbles within the controlled barrier fluid, creating a more controlled and efficient approach to underwater noise abatement.
Small bubbles. Significant acoustic effect.
Designed for offshore reality
Engineered for offshore deployment. Designed to scale.
Pulcea is developing its high-performance bubble curtain for the practical realities of offshore wind, with the potential to deliver effective noise attenuation, reduced offshore complexity, scalable deployment and a smaller operational footprint – whilst supporting marine protection and environmental compliance.
Pulcea’s work supports the ambitions of the UN Sustainable Development Goals, helping enable the continued development of offshore wind whilst reducing its impact on the marine environment.
From science to evidence
Pulcea has progressed from scientific principle through laboratory experimentation, modelling and onto controlled testing, steadily building the evidence for offshore application.
Testing has demonstrated the acoustic potential of the approach and enabled Pulcea to understand the relationship between bubble characteristics, fluid properties and sound attenuation.
Independently Verified
Broad Frequency Attenuation
Up to 21.2 dB Modelled Reduction
Controlled testing has demonstrated measurable sound attenuation across a broad frequency range, with subsequent modelling indicating particularly strong reductions at higher frequencies.
Based on the measured insertion loss, modelling by Seiche’s acoustic experts indicates the potential for up to 21.2 dB reduction in weighted sound exposure for very high-frequency cetaceans, such as the harbour porpoise.
With the acoustic principle demonstrated, the next stage is open-water validation at an appropriate scale, building the evidence base for practical offshore deployment.
These open-water testing programmes will also include refining and then assessing the methodology for improving low and medium frequency performances.
Work with Pulcea
Reducing underwater noise is both an environmental and an engineering challenge.
Pulcea’s goal is to support the continued growth of offshore wind while reducing its acoustic impact on the marine environment, bringing together science, engineering and practical offshore deployment.
Pulcea welcomes conversations with offshore wind developers, installation contractors, technology partners, philanthropic and research organisations and investors interested in supporting the next stage of development.