Marine biomass and circular value chains in the Baltic Sea

This blog post documents a student-led exploration conducted within the WAVE project, focusing on how marine biomass, such as macroalgae, eelgrass and reed can be better integrated into sustainable value chains. The study combines literature analysis, system mapping, and stakeholder engagement through surveys across five segments of the value chain: primary production, processing, bio-based materials, aquaculture, and supporting actors.

The results suggest that while actors exist throughout the value chain, the system remains fragmented, limiting large-scale implementation. Key challenges include seasonal variability, logistical inefficiencies, processing limitations, and market barriers. At the same time, opportunities emerge in higher-value applications such as bio-based materials and chemicals.

Overall, marine biomass in the Baltic Sea context represents both an environmental challenge and an untapped opportunity, requiring integrated solutions across disciplines to support the development of a sustainable blue bioeconomy.

Introduction

The growing pressure on global food systems, natural resources, and energy supply has underlined the need for more resilient and sustainable bioeconomy models, increasingly evident. Population growth continues to raise demand for food, materials, and energy, while climate change disrupts agricultural productivity and accelerates ecosystem degradation. At the same time, geopolitical instability has revealed how vulnerable global supply chains can be, particularly in energy, fertilisers, and key raw materials (European Commission, 2017; Gurría et al., 2022).

In response, circular economy thinking has gained ground across industries. Rather than following an unsustainable linear model, circular approaches aim to retain value in materials and transform waste streams into new resources (Geissdoerfer et al., 2016; Kirchherr & Hekkert, 2017). One emerging extension of this idea is the blue bioeconomy, which focuses on how aquatic resources can contribute to more sustainable production systems.

Marine biomass plays a central role in this discussion. Although oceans cover more than 70% of the Earth’s surface, they remain largely underutilised as a source of biomass. In regions such as the Baltic Sea, nutrient-driven eutrophication leads to the accumulation of algae, seaweed, and coastal plants such as eelgrass (Zostera marina), much of which washes ashore and is treated as waste. At the same time, this biomass represents a renewable resource with untapped potential (Gurría et al., 2022; Duarte et al., 2017).

Macroalgae and other marine biomasses are especially promising due to their rapid growth and minimal resource requirements. However, their high-water content, seasonal variability, and logistical challenges continue to limit large-scale utilisation (Milledge, Nielsen & Harvey, 2016; Zhang et al., 2021).

This blog post follows our team’s exploration within the WAVE project, focusing on how these materials can be better integrated into circular and sustainable value chains. To better understand how these opportunities and challenges are currently addressed in practice, a structured methodological approach was developed.

Methodology

The methodology combines literature research, system mapping, and stakeholder engagement to explore how marine biomass is produced, processed, and utilised within the Baltic Sea region. The approach aimed to connect theoretical knowledge with practical perspectives from across the value chain.

The first phase consisted of a structured literature review. Scientific publications, policy documents, and project reports were analysed through a process of identification, screening, and synthesis using keywords such as “algae AND circular economy,” “seaweed AND circular economy,” and “eelgrass AND circular economy” were used to guide the search. This phase defined key themes such as biomass availability, processing challenges, and value chain fragmentation.

In parallel, a system mapping exercise identified actors across the value chain, including biomass production, processing, applications, and supporting organisations. The findings indicate that while actors exist across all stages, connections between them remain limited, suggesting a fragmented system.

To complement these insights, a survey-based approach was developed. Surveys were structured into five stakeholder groups: primary production and food chains; processing and biorefinery technologies; bio-based materials; aquaculture systems; and supporting actors.

The survey design was largely driven by the WAVE student group, who initially formulated questions based on their own interests and what they aimed to better understand within the system. These ideas were then organised into broader thematic categories and further refined using insights from the literature review and system mapping. Themes such as biomass availability, logistics, processing, and market development were translated into concrete survey questions reflecting real-world challenges.

A mixed-question format was used, combining multiple-choice questions, scaled responses (0–5), and open-ended questions. This allowed respondents to evaluate challenges while also providing context. While each stakeholder group received a tailored survey, a shared core structure ensured comparability across responses.

The survey was distributed to 26 companies, with 12 responses collected across different stakeholder groups. While the response rate was limited, the structure of the survey enabled identification of recurring patterns across the system.

The collected insights were then synthesised into key challenge areas to guide further exploration and future innovation work.

Results

The results combine insights from mapping and stakeholder survey responses to provide an overview of current practices and challenges in marine biomass utilisation in the Baltic Sea region. A total of 12 responses were collected from 26 contacted companies, covering actors from production to end-use applications.

The system mapping indicates a diverse ecosystem of actors across the value chain, ranging from upstream producers to downstream product developers, as well as supporting actors such as research institutions and platforms. However, the findings suggest that the value chain remains fragmented. While these actors exist across all stages, stronger integration between production, processing, and market deployment is still limited, which restricts the development of scalable systems.

One of the clearest findings relates to raw material availability and variability, particularly highlighted by respondents in primary production and food value chains (Group 1). Biomass supply is strongly dependent on environmental conditions, leading to seasonal fluctuations and inconsistencies in quality. As one respondent noted, “biomass availability is highly seasonal and difficult to predict,” while another emphasised that “quality varies significantly depending on environmental conditions.” These issues directly affect the reliability of biomass as a feedstock and create uncertainty for downstream processes.

Additionally, Group 1 responses revealed challenges related to value creation and competitiveness. For example, one respondent working with seaweed-based products stated that “biostimulants have limited possibilities and it is difficult to find competitive advantages.” Another highlighted that “food is only a small fraction of the seaweed value chain, and the main volumes will come from ingredients to large industries,” suggesting that marine biomass must compete with or outperform land-based inputs to become economically viable.

Responses related to reed as a biomass further underline technical and systemic challenges. One respondent pointed to an “underdeveloped understanding of efficient stabilisation processes,” particularly in achieving cost-efficient and scalable solutions. At the same time, opportunities were identified in integrating biomass harvesting with existing industries, as one response suggested that “operational costs could be reduced through seasonal integration into the fishing industry.” These insights highlight both the current limitations and potential synergies within the system.

A second major challenge across stakeholder groups is logistics and value chain coordination. Respondents consistently identified logistics as a bottleneck, particularly due to the high moisture content and bulkiness of marine biomass. One respondent described logistics as “one of the main bottlenecks in scaling operations,” reflecting the difficulty of transporting and storing biomass efficiently. In addition, limited coordination between producers and processors leads to mismatches in supply and demand, further reducing system efficiency.

From a technological perspective, processing and scalability remain critical constraints. Respondents noted challenges related to drying, pre-treatment, and extraction processes, which increase costs and complicate large-scale implementation. In material-focused sectors, additional concerns include achieving performance levels – such as durability and consistency – that can compete with conventional alternatives.

Market-related challenges were also widely reported, particularly in relation to market development and cultural acceptance. In the food sector, barriers such as regulatory frameworks, distribution channels, and consumer preferences were identified. Cultural factors also play a significant role, as marine ingredients such as seaweed are more strongly associated with Asian cuisines and are not traditionally embedded in European – especially Baltic – food cultures. As reflected in responses, “consumer awareness is still low,” and the introduction of such products requires “significant effort in market education.”

At the same time, responses from aquaculture and production-focused actors (Group 4) suggest that market dynamics are a central uncertainty. One respondent noted that there is an “underdeveloped market, but multiple opportunities as long as the market is there, ”highlighting the dependency of production systems on future demand development.

In contrast, responses from supporting actors and system innovators (Group 5) emphasised emerging opportunities beyond traditional food applications. These include the development of “new markets outside the food industry, such as packaging and bioplastics,” indicating a shift toward higher-value and more scalable applications of marine biomass.

Overall, the results indicate that while the current system faces significant challenges, there is strong potential in transitioning toward higher-value applications. Compared to low value uses such as energy, sectors like materials, chemicals, and industrial applications offer greater economic potential and better alignment with circular economy principles. Environmental benefits, including nutrient removal and carbon capture, were also identified as important value drivers that could further support these developments.

The identified challenges can be summarised into three main categories:

• Technical challenges: improving processing efficiency, scalability, and material performance
• Business challenges: strengthening value chain integration, logistics, and market competitiveness
• Environmental challenges: ensuring sustainable harvesting and managing ecosystem impacts

Overall, the results suggest that marine biomass represents both a complex system challenge and a significant opportunity. Addressing these challenges requires not only technological improvements, but also better coordination between stakeholders and stronger market development to enable large-scale implementation.

Personal insight

Working on this topic has highlighted how closely environmental challenges and economic opportunities are interconnected within marine systems. Biomass that is often perceived as waste – such as algae accumulation – can, when viewed through a circular perspective, become a valuable resource.

At the same time, the process revealed that the key barriers are not only technological, but largely systemic. Fragmentation across actors, limited coordination, and challenges in scaling solutions often prevent ideas from moving beyond pilot stages.

This experience also emphasised the importance of interdisciplinary approaches. Addressing marine biomass challenges requires combining environmental science, engineering, and business perspectives, while also considering policy frameworks and societal acceptance. Future progress will depend on the ability to connect these elements into more integrated and functional systems.

Paula Linderbäck, Principal lecturer in circular economy
Co-writers: Dimitrios Kourouvakalis, Miguel Limachi Tapia

References

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European Commission, Directorate-General for Research and Innovation & Group of Chief Scientific Advisors 2017. Food from the oceans: How can more food and biomass be obtained from the oceans in a way that does not deprive future generations of their benefits?Luxembourg: Publications Office of the European Union. Available at: https://doi.org/10.2777/66235

European Commission, Executive Agency for Small and Medium-sized Enterprises, Technopolis Group & Wageningen Research 2020. Blue Bioeconomy Forum: Highlights – synthesis of the roadmap and a selection of viable and innovative projects. Luxembourg: Publications Office of the European Union. Available at: https://doi.org/10.2826/746132

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