A science lesson on biomass has led a seventh-grade student in Texas to develop an experiment that could offer new insights into algae-based biofuel production.
Arya Hirsave, a student at Canyon Vista Middle School in Austin, became interested in algae after learning about renewable and non-renewable energy. Her research examined whether microscopic algae could be encouraged to grow more efficiently and produce more lipids, or oils, that can be used as a feedstock for biofuels, The Economic Times reported.
Her project, titled “Micro’fat’ories: Increasing Microalgal Biomass and Lipids for Biofuel Production,” was selected as a finalist for the 2025 Thermo Fisher Scientific Junior Innovators Challenge.
According to the Society for Science, Hirsave became interested in the subject after encountering the term “biomass” in her science class. She focused on algae because they can absorb carbon dioxide through photosynthesis and could serve as a renewable resource.
She tested four types of microalgae — Chlorella vulgaris, Chlorella pyrenoidosa, Nannochloropsis and Tetraselmis chuii. The first two are freshwater species, while the other two are saltwater algae.
Her initial tests found that Chlorella vulgaris and Nannochloropsis were among the fastest-growing species. She then examined whether changes in their growing conditions could increase both growth and lipid production.
Vitamins boosted growth, while salt increased lipids
Hirsave tested vitamins B and C and plant hormones to see whether they could improve algae growth. The results showed that the vitamins supported photosynthesis and increased growth by 6-7%, according to the Society for Science.
She then looked at lipid production, which is important for algae-based biofuel because the oils stored inside the cells can potentially be converted into fuel.
Adding salt to freshwater algae produced a different result. Higher salt concentrations slowed algae growth but increased lipid production.
The finding led Hirsave to consider using the two approaches at different stages rather than trying to maximise growth and lipid production at the same time.
Five-day treatment increased lipid production by 77%
In her most notable experiment, the algae were first treated with vitamins for three days to support growth and photosynthesis. They were then exposed to high levels of salt for two days.
The five-day treatment increased lipid production by 77%, according to the Society for Science.
The experiment showed that conditions that encourage algae to grow quickly may not be the same as those that encourage them to produce more oils. By first supporting growth and then applying environmental stress, Hirsave was able to increase lipid production.
The findings do not establish a commercial algae-based biofuel process. Further research would be needed to determine whether the approach can be reproduced at a larger scale and under commercial production conditions.
Hirsave has taken part in science fairs since third grade and has explored a range of scientific subjects. She is also interested in astronomy and has studied topics including the black hole TON 618.
Her long-term goal is to become an astrophysicist.
For now, her algae research has earned national recognition through her selection as a finalist in the 2025 Thermo Fisher Scientific Junior Innovators Challenge, showing how a question raised in a middle-school science class can develop into research with potential applications in renewable energy.
