Solar Power Technologies for Sustainable Biofuel Production

The SUNFUSION project, funded by the European Union under Horizon Europe, has been launched in January 2025 with a vision to advance sustainable biofuel production from purified microalgae and oleaginous yeasts by utilising state-of-the-art solar technologies. Coordinated by CERTH, this four-year initiative unites 10 partners from 6 countries, working together to provide sustainable aviation and shipping fuel alternatives.

Why Does SUNFUSION Matter?

SUNFUSION is dedicated to accelerating the EU’s renewable energy transition by integrating solar energy into multiple production processes and focusing on energy efficiency and zero waste principles.

The European Union’s transition to renewable energy sources aims to increase the 2030 renewable energy target to 45%. One of the key challenges remains the integration of renewable energy into the transportation sector, which accounted for 30% of the EU’s total energy consumption in 2022. Biofuels, derived from biomass, offer a promising solution.

These fuels can replace fossil fuels while using existing infrastructure for transportation and storage, reducing the need for costly investments in new engines and tanks. Microalgae & oleaginous yeasts offer promising alternative as efficient lipid producers, requiring minimal resources compared to traditional oil plants. This makes biofuels a cost-effective and viable alternative, helping to drive the green transition forward while reducing dependency on conventional energy sources.

Project coordinator from Centre for Research & Technology Hellas (CERTH), Nikolaos Tsongidis, highlights key points of SUNFUSION innovation:

SUNFUSION is pioneering a sustainable pathway for the production of advanced aviation and marine biofuels by leveraging microalgae and oleaginous yeasts, integrated with concentrated solar technologies. Our project combines a series of cutting-edge technologies —from innovative cultivation systems to solar-assisted hydrothermal liquefaction, thermal energy storage and upgrading— pushing the boundaries of biofuel production while minimizing emissions and waste.

By demonstrating the process at TRL 4 and targeting a solar-to-biocrude oil efficiency target exceeding 50%, our aim is to set new benchmarks in renewable energy technologies. As the Coordinator of the project, I am proud to collaborate with a distinguished Consortium of experts across Europe, working together to drive the future of sustainable aviation and shipping fuels by actively promoting the European green transition plan.

SUNFUSION – 4 Pillars of Innovation

The SUNFUSION project is built upon four core pillars which are based on biological and thermochemical processes resulting in sustainable fuel products and byproducts:

Advanced photobioreactors and open raceway ponds for the cultivation and purification of microalgae and oleaginous yeasts
A continuously operating Hydrothermal Liquefaction reactor powered by Concentrated Solar Thermal energy
Hydrotreatment units for producing sustainable aviation fuels and marine fuels, along with research on future solar integration and
Solar-assisted Thermal Energy Storage systems.

Technologies Beyond SUNFUSION

The project aims to achieve significant advancements in several key technologies and processes:

Optimized Biomass Cultivation and Purification: SUNFUSION will optimise cultivation parameters to produce high-lipid, low-nitrogen microalgal biomass, significantly reducing production costs. The project will also establish a dual lipid-rich biomass system integrating yeasts and microalgae for enhanced efficiency.
Advanced Hydrothermal Liquefaction (HTL) Technologies: The project will develop a kinetic model for HTL conversion of microalgae, considering initial biochemical composition. A sophisticated reactor model, incorporating fluid dynamics, chemical reactivity, and solar heating, will be created, followed by implementation of the continuous HTL for biocrude production from microalgae and yeasts, along with membrane-based CO₂ valorisation of post-HTL gaseous streams.
Innovative Thermal Energy Storage (TES): A flexible and scalable TES system, designed to be charged with parabolic trough collectors, will be developed and a lab-scale prototype will be constructed to demonstrate its effectiveness.
Solar-Powered Continuous HTL Reactor: SUNFUSION will design and construct a lab-scale continuous solar HTL reactor. Continuous HTL operation with optimised solar heating will be implemented, determining optimal conversion conditions for desired temperature and residence time.
Biocrude Upgrading for High-Value Fuels: The project will develop hydrotreatment processes (mild and deep) and fractionation techniques to upgrade HTL biocrude, maximising the production of kerosene and marine fuel products.

SUNFUSION aims to demonstrate the feasibility and efficiency of a solar-powered biorefinery, contributing significantly to the EU’s renewable energy goals. By integrating advanced technologies for biomass cultivation, HTL conversion, thermal energy storage, and biocrude upgrading, SUNFUSION will pave the way for a sustainable and economically viable biofuel industry.

Sustainability, collaboration and impact

The SUNFUSION project is dedicated to significantly advancing sustainable energy production. It will cultivate and select five high-performing, energy-efficient strains, converting approximately 40% of biomass into sustainable fuels and achieving solar-to-biocrude energy conversion efficiency exceeding 50%.

It is expected to achieve an 80% round-trip efficiency in its Thermal Energy Storage (TES) system, leveraging concentrated solar heat for both hydrothermal liquefaction (HTL) and biofuel upgrading processes, while also harnessing natural sunlight. Building upon these technical advancements, SUNFUSION is deeply committed to fostering sustainability, collaboration, and impactful change.

With a foundation of modular design, circular economy principles, and continuous stakeholder engagement, the project aims to revolutionise biofuel production.

By actively fostering collaboration among microalgal and biofuel producers, researchers, policymakers, and industry, SUNFUSION will not only drive technological innovation but also pave the way for a secure, environmentally responsible energy future, significantly reducing dependence on traditional fossil fuels and creating lasting positive impact.

All relevant information is available on the project’s website, as well as through its social media channels: LinkedIn, Facebook, Instagram and X . Follow us for more!