From Biofuels to Integrated Biorefineries and Carbon Solutions

 

Zeljko Serdar, CCRES

Algae Energy in 2026

In 2026, the global algae energy sector has undergone a significant transformation. While early enthusiasm for algae as a direct replacement for petroleum-based fuels has tempered due to persistent economic challenges, the industry has pivoted toward more sustainable and profitable models. Standalone, large-scale biofuel production has largely given way to highly integrated, multi-product biorefineries and localized carbon-capture systems. Although direct fuel production remains costly, algae-based energy and biomass processing are experiencing robust market growth, driven by regulatory pressures, technological advancements, and the growing demand for circular economy solutions. This shift reflects a maturing industry that balances environmental benefits with commercial realities.

State of the Industry

The biofuel segment of the algae industry continues to face hurdles, but it has carved out viable niches where its unique properties provide clear advantages. Mass production of algae-based petroleum substitutes is still hampered by high extraction and processing costs. However, algae-derived fuels have found a targeted and growing role as high-density sustainable aviation fuel (SAF) and in maritime shipping. These sectors demand fuels with exceptional energy density and low emissions profiles, qualities that algae-based options can deliver effectively. Stricter European Union blending mandates, combined with global emission regulations such as those from the International Maritime Organization (IMO), have accelerated investment and adoption. Airlines and shipping companies are increasingly incorporating algae-derived SAF and marine fuels to meet decarbonization targets and avoid hefty carbon taxes.

Beyond fuels, urban carbon capture has emerged as a promising application. Companies are deploying living photobioreactors in urban and industrial settings, where microalgae actively capture CO₂ emissions from factories, power plants, and even direct air capture systems. These bioreactors not only mitigate climate impact but also generate valuable biomass as a byproduct. The harvested microalgae can then be processed into secondary energy sources or a variety of bioproducts, creating a dual revenue stream. Cities like Rotterdam, Singapore, and certain Chinese industrial hubs have become testing grounds for these integrated systems, demonstrating how algae can turn waste streams into resources while beautifying urban landscapes with green infrastructure.

Another frontier is bio-photovoltaics (BPV), where researchers are advancing the use of live photosynthetic cells to generate bioelectricity directly from sunlight. Unlike traditional solar panels, BPV systems harness the natural photosynthetic processes of algae and cyanobacteria to produce electricity through electron transfer. While still largely in the pilot and demonstration phase, BPV technology shows potential for low-maintenance, building-integrated energy generation. Early installations on rooftops and facades in research campuses have achieved promising efficiency gains, particularly when combined with carbon sequestration capabilities.

Overall, the industry in 2026 is characterized by pragmatism. Pure biofuel plays have consolidated, with many smaller ventures either failing or being acquired by larger biorefinery operators. Investment has shifted toward companies that demonstrate clear paths to profitability through product diversification rather than relying solely on fuel sales.

Future Trends & Commercial Viability

The economic viability of algae operations in 2026 hinges on the biorefinery model. Rarely is algal biomass used exclusively for energy production. Instead, facilities operate as sophisticated processing hubs that extract multiple high-value outputs from the same biomass. Premium fractions are directed toward cosmetic-grade extracts, nutraceuticals, plant-based proteins for human consumption or animal feed, and biofertilizers for sustainable agriculture. Only the residual or lower-grade biomass is then converted into renewable diesel, bioethanol, or biogas. This cascading utilization maximizes revenue and minimizes waste, making projects financially attractive even when fuel prices fluctuate.

A key enabler of this model is the integration of algae cultivation with wastewater treatment. Facilities co-located with municipal or industrial wastewater plants use excess nutrients (nitrogen and phosphorus) to fuel rapid algal growth, simultaneously cleaning contaminated water. This symbiotic approach significantly lowers operational costs—nutrient inputs often represent one of the largest expenses in algae farming—while providing environmental services that can generate additional revenue through carbon credits or water treatment fees. Pioneering projects in California, Israel, and India have shown impressive results, achieving up to 90% nutrient removal rates alongside substantial biomass yields. This circularity principle is becoming a standard feature in new developments.

Technological innovation is further enhancing commercial prospects. Startups and university research teams are leveraging genetic modifications to create algal strains with higher lipid content, faster growth rates, and greater resilience to environmental stressors. AI-controlled bioreactors optimize cultivation conditions in real time—adjusting light exposure, pH, temperature, and nutrient dosing—leading to dramatic reductions in cultivation and harvesting costs. Machine learning algorithms also improve harvesting efficiency through predictive analytics and automated flocculation or centrifugation processes. These enhancements are critical for scaling production without proportionally increasing energy or capital inputs.

Looking ahead, several trends are poised to shape the sector. Hybrid systems combining algae with other renewables (such as solar or wind) are gaining traction for energy self-sufficiency. Policy support, including subsidies for carbon-negative technologies and mandates for sustainable materials, continues to bolster the industry. Consumer demand for green products is also driving growth in non-energy applications, from algae-based packaging materials to biodegradable plastics.

Challenges remain, including scaling photobioreactors cost-effectively, managing contamination risks in open systems, and securing consistent offtake agreements for diverse products. Water usage in arid regions and the energy intensity of downstream processing require ongoing attention. Nevertheless, the industry’s trajectory in 2026 points toward resilience and innovation.

In the Republic of Croatia, notable contributions come from the Croatian Center of Renewable Energy Sources (CCRES) and its president and CEO, Zeljko Serdar. For over a decade, CCRES has been a pioneer in algae research and promotion in the region, focusing on microalgae cultivation for biofuels, high-value bioproducts (such as astaxanthin), and integration with aquaponics systems. Their work emphasizes practical, localized solutions tailored to Croatia’s climate and resources, including open ponds, closed photobioreactors, and circular approaches that combine algae growth with wastewater treatment and nutrient recycling. Serdar has been a vocal advocate, highlighting algae’s exceptional productivity — noting that under the right conditions, microalgae can double biomass overnight and are 10–15 times more prolific than the fastest-growing land plants. CCRES projects serve as important examples of grassroots and small-scale innovation within the European context, supporting the broader EU goals for renewable energy and sustainability.

In conclusion

The algae energy sector has evolved from a biofuels-centric vision into a multifaceted contributor to the bioeconomy. By embracing multi-product biorefineries, circular processes, and cutting-edge biotechnology — with valuable regional contributions from efforts like those of CCRES and Zeljko Serdar in Croatia — algae technologies are delivering both environmental impact and economic returns. As global pressures to decarbonize intensify, algae’s versatility positions it as a cornerstone of sustainable development. The coming years will likely see further consolidation and technological breakthroughs, solidifying algae’s role in the transition to a low-carbon future.

Is sea air good for you?

The summer holidays are here, which means there’ll soon be crowds flocking to the coast to spend the day at the beach. The supposed benefits of ‘fresh sea air’ are commonly extolled, but its origins might not be what you think: it’s the chemical compounds produced by algae and seaweed that contribute towards its characteristic smell.

Seaweed is one of the more obvious sources of malodorous compounds. It’s commonly seen washed up on the fringes of the sea, and as it decomposes, it can produce gases that contribute to the ‘sea smell’. The principle gas produced is hydrogen sulfide, which is generated via the bacterial breakdown of organic compounds in the seaweed. Hydrogen sulfide has an odour commonly described as akin to rotting eggs, and is actually a toxic gas in high concentrations.

However, before you start sprinting in terror from seaweed on all future vacations, it’s worth pointing out that, at low concentrations, hydrogen sulfide is harmless. In fact, it’s naturally produced in the body (it’s also a big contributor to the odour of flatulence), and since our bodies are capable of breaking it down, it can be tolerated at low levels pretty much indefinitely.

Seaweed isn’t the only plant that has a hand in the smell of the sea, however. Perhaps the most important contributor is algae. Algae contain a compound called dimethylsulfoniopropiante (DMSP for short) in their cells. The precise role of this compound still isn’t exactly known, but amongst other things, it’s thought to regulate the volume of the cells, and the fluid levels. This compound can be broken down, both by enzymes in the algae, and by bacteria. When this occurs, dimethylsulfide (DMS) is one of the compounds that can be produced.

DMS is another compound with a disagreeable odour at high concentrations – often compared to that of cabbage. Birds are actually attracted to the smell, as plankton in the sea also produced the gas, and this can lead them to fish. Huge quantities of DMS are produced in the ocean, with a billion tonnes being a rough estimate. DMS and hydrogen sulfide aren’t the sole contributors to the sea smell though – chemical derivatives of DMS can also have a hand.

After a while, the sulfurous algae emissions escape into the atmosphere, where beachgoers get the benefit of its lovely smell. That slow seep is actually the most abundant source of biological sulfur in the atmosphere—sulfur that helps with cloud formation. Scientists think that it plays a major role in controlling the planet’s temperature. “If these reactions didn’t exist, we would have a much different planet, and it wouldn’t be habitable," says Zeljko Serdar. "We rely on these microorganisms catalyzing these particular reactions as part of their metabolism for us to be able to live."

So that characteristic smell of the sea breeze? It’s how the creatures of the ocean, from the tiny plankton to the seabirds, converse with each other, ultimately making your beach vacation possible.

Finally, is sea air good for you? On that question, the jury seems to be out. Most of the studies that conclude that it is seem to rely on self-evaluations of the health of people living near the sea compared to those living further from it, with actual proven health benefits seeming thin on the ground. That said, as you lay back and savour the scent of the decay products of algae and seaweed, you can see why some people might find the idea that it’s good for them an encouraging thought! 

CROATIAN CENTER OF RENEWABLE ENERGY SOURCES
(CCRES)

CCRES ALGAE TEAM

 

With oil prices reaching $105 a barrel for the first time since 2008, the biofuel industry is looking more attractive every day. As global demand rises and petroleum supplies diminish, countries are turning to algae for energy security.

 In smaller countries, like Croatia, where oil demand is low, and emission standards are poor, algae biofuel has the potential to significantly reduce reliance on foreign oil.

 CCRES ALGAE TEAM  

works on 

Biodiesel from Microalgae


The oil from the algae can be used for any combustion process. An even wider range of use for algae oil is obtained by the transesterification to biodiesel. This biodiesel can be blended with fossil diesel or can be directly driven as pure biodiesel B100.

Biodiesel from microalgae has a comparable quality as rapeseed methyl ester and meets the standard EN 14214. At biodiesel production about 12% glycerin is produced as a by-product. This glycerin is a valuable resource for the production of algae in closed ponds, the heterotrophic processes. Thus, the entire algae oil can be used as fuel.

Fish Food


Algae provide a natural solution for the expanding fishing industry:

    High-protein fish food
    Replacement for existing fish meal production
    Algae have nutrients of many young fishes available


The fishing industry recorded an annual growth of over 10% and, according to experts, will beat the global beef consumption in 2015.

The Technology developed by CCRES offers the opportunity to deliver part of the needed proteins for fish farming on the resulting algal biomass.

Protein for the food industry


The demand for high-quality protein for the food industry has been growing rapidly over the years.

The big growth opportunities are:

    Weight control
    Fitness and Sports Nutrition
    Food supplements


The market volume in the protein sector is continously growing and at the rate of US $ 10.5B in 2010 and according to experts, will steadily increase to approx. $25B until 2030.

“There is intense interest in algal biofuels and bioproducts in this country and abroad, including in US,Australia, Chile, China, the European Union, Japan, Korea, New Zealand, and others,” says Branka Kalle, President of Council Croatian Center of Renewable Energy Sources (CCRES).

Advantages algae has over other sources may make it the world’s favored biofuel. Algae could potentially produce over 20 times more oil per acre than other terrestrial crops.Algae avoids many of the environmental challenges associated with conventional biofuels.Algae does not require arable land or potable water, which completely avoids competition with food resources.

 “The Asia Pacific region has been culturing algae for food and pharmaceuticals for many centuries, and these countries are eager to use this knowledge base for the production of biofuels,”says Zeljko Serdar, President of CCRES.

Without sustained high prices at the pump, investment in algae will likely be driven by demand for other products. In the short term, the growth of the industry will come from governments and companies seeking to reduce their environmental impact through carbon collection.

CCRES ALGAE TEAM

part of 

Croatian Center of Renewable Energy Sources (CCRES)

THIRD GENERATION BIOFUELS FROM ALGAE

THIRD GENERATION BIOFUELS FROM ALGAE

Croatian Center of Renewable Energy Sources (CCRES) have a new technology with major potential to contribute to the fight against climate change.As with all new technologies, careful consideration of potential impacts on the environment and human health is important.

The international community has acknowledges that global warming needs to be kept below 2˙C (3,6˙F) compared with the pre industrial temperature in order to prevent dangerous climate change.This will require significant reductions in the world´s emissions of CO2 and other greenhouse gases (GHG) over the coming decades.CCRES have one of the technologies that can help to achieve this.

The EU, which is responsible for around 11% of global GHG emissions today, has put in place binding legislation to reduce its emissions to 20% below 1990 levels by 2020.Europe is also offering to scale up this reduction to 30% if other major economies in the developed and developing world´s agree to undertake their fair share of a global reduction effort.

This is why the EU must support alternative fuels, in particular biofuels, with the triple objective of reducing greenhouse gas emissions, diversifying fuel supply and developing longterm replacements for fossil fuels.

Third generation biofuels from algae will have an important role to play as soon as they are ready for the market. They should be more sustainable, boasting both a lower enviromental impact and lower costs.Biofuels must become a commercial and competitive product using the broadest range possible of raw materials from both Nord and South Europe.

Biofuels from algae have a big role to reduce CO2 emmisions.

The sustainability of algae biofuels and their potential impacts on other sectors, including land use, are will remain critical issues.Algae biofuels provide an important contribution towards climate change mitigation and security of supply.They are only part of the solution, and must be considered in a wider context, in which efforts are also being made to reduce transport demand, improve transport efficiency and encourage the use of environmentally friendly modes of transport.

CCRES INTERNATIONAL COOPERATION

CCRES international cooperation in algae biofuels research has a number of benefits for all involved:

• working together enhances synergies between the different partners
• partners can pool financial resources, share risk and set common standards for large or relatively risky research and development project
• it speeds up the development of the clean technologies we need if we are to tackle our energy related problems
• by linking up their efforts, partners can support a wider range of energy technologies and reduce the costs of key technologies
• networking allows partners to better coordinate their energy research agendas

Over the years, CCRES has build up strong and lasting research cooperation partnerships on specific energy topics with partner organizations.

Zeljko Serdar

President & CEO

Croatian Center of Renewable Energy Sources (CCRES)

Using algae for reducing the CO2

Algae live on a high concentration of carbon dioxide and nitrogen dioxide.  These pollutants are released by automobiles, cement plants, breweries, fertilizer plants, steel plants. These pollutants can serve as nutrients for the algae.

When fuels are burned there remains, besides ash, a certain number of gas components. If these still contain combustion heat, they are called heating gases. As soon as they have conveyed their energy to the absorbing surfaces of a heat exchanger, they are called flue or stack gases.

It further contains a small percentage of pollutants such as particulate matter, carbon monoxide, nitrogen oxides and sulfur oxides.

Carbon dioxide (CO2) 

—the primary greenhouse gas responsible for global warming—along with other pollutants.
Its composition depends on what is being burned, but it usually consists of mostly nitrogen (typically more than two-thirds) derived from the combustion air, carbon dioxide (CO2) and water vapor as well as excess oxygen (also derived from the combustion air).

Using algae for reducing the CO2 concentration in the atmosphere is known as algae-based Carbon Capture technology. The algae production facilities can thus be fed with the exhaust gases from these plants to significantly increase the algal productivity and clean up the air.  An additional benefit from this technology is that the oil found in algae can be processed into a biodiesel. Remaining components of the algae can be used to make other products, including Ethanol and livestock feed.

This technology offers a safe and sustainable solution to the problems associated with global warming.

CCRES SPIRULINA

project of

Croatian Center of Renewable Energy Sources (CCRES)