One of the paradoxes of using microalgae for biofuel production is that they can get too much of a good thing. Under intense sunlight—exactly when you’d want maximum photosynthetic output—these microscopic organisms often trigger protective mechanisms that reduce their efficiency, slowing growth and lipid production.
Our partners in the EU-funded SUN-PERFORM project have demonstrated a promising solution: an “ATP-battery” that helps microalgae manage energy more effectively under light-saturated conditions.
Igor Vunderink, a PhD candidate working on solar-to-fuel conversion in microalgae at Wageningen University & Research, presented preliminary results at the Netherlands Biotechnology Congress in September 2025. He showed that genetically engineered microalgae containing this ATP-battery system achieved improved growth rates compared to unmodified strains.
How the ATP-battery works
The concept is theoretically simple: engineer proteins to temporarily store solar energy within the microalgae, preventing waste during peak light conditions and improving overall productivity—a buffer against energy fluctuations.
The team inserted arginine kinase enzymes into Nannochloropsis oceanica, an industrially relevant microalga that naturally accumulates oils suitable for aviation fuel. These enzymes convert ATP (the cell’s standard energy unit) and arginine into arginine phosphate—a high-energy storage molecule. When energy demand increases, the reaction reverses, releasing ATP back into the system.
“The ATP-battery aims to reduce the photo-inhibitory effect caused by excessive light,” Igor explains.
Under intense illumination, microalgae normally activate non-photochemical quenching (NPQ)—a protective mechanism that dissipates excess light energy as heat. While this prevents cellular damage, it also diverts energy away from photosynthesis, ultimately reducing both growth and lipid production.
By providing an alternative outlet for excess energy, the ATP-battery system could alleviate these losses and enhance overall photosynthetic performance.
Multiple strategies, one goal
The ATP-battery represents one of several complementary approaches the SUN-PERFORM consortium is pursuing to make algae-based biofuels economically competitive with fossil fuels.
At the same conference, Áureo Cutillas Farray presented work on implementing synthetic carbon fixation pathways that bypass the inefficiencies of the natural photosynthetic enzyme RuBisCO. These engineered pathways use bicarbonate directly and generate acetyl-CoA—a key building block for lipid synthesis—without the carbon losses associated with photorespiration.
This work will attempt the first implementation of a complete synthetic carbon fixation pathway in microalgae. If successful, it could significantly improve both photosynthetic efficiency and net carbon capture.
The consortium is also developing light-converting nanocrystals that shift sunlight into the far-red wavelengths microalgae prefer.
“We’re attacking the efficiency problem from multiple angles,” says Sarah D’Adamo, the project’s coordinator. “Light optimization, carbon fixation, and energy management all need to work together to make microalgae competitive as biofuel producers.”
In her keynote presentation, Sarah outlined how the team is building on Nannochloropsis oceanica’s natural advantages—efficient TAG accumulation and omega-3 production—while systematically addressing biological bottlenecks through genetic engineering.
From lab to application
The Netherlands Biotechnology Congress provided an opportunity for the SUN-PERFORM team to engage with both academic researchers and industry representatives working across biotech applications.
The aviation and shipping sectors are particularly difficult to decarbonize because they require energy-dense liquid fuels that current battery technology can’t provide. Microalgae-based biofuels offer a potential solution, but only if production costs can be brought down significantly.
The ATP-battery results are preliminary—the team is still characterizing exactly how the system affects metabolic efficiency and lipid production under different conditions. But the improved growth rates under light saturation suggest the approach is worth pursuing.
As these complementary strategies mature, the question becomes whether their combined effect can push microalgae cultivation past the economic threshold where it competes with fossil fuels—not just on sustainability, but on price.