Utilization of coal-fired power plant CO2 in Yalova through photobioreactors: A comparative parametric study based on OpenFOAM–CFD, Gibbs energy minimization, and two-stroke drone engine performance evaluation

• Microalgae-based PBRs modeled for CO 2 capture from a coal plant in Yalova. • OpenFOAM–CFD and Gibbs free energy applied for biomass-to-fuel pathways. • Biodiesel, hydrogen, and SAF yields quantified under different scale scenarios. • Engine trials show biodiesel–H 2 blends improve BTE (+28 %) and cut CO/HC (−50 %). • Validation with field data confirms conservative but realistic performance estimates. This work assesses the capture of CO 2 from a coal plant’s flue gas in Yalova, Turkey, with closed photobioreactors (PBRs) growing microalgae. For biomass utilization, options include direct co-firing, biodiesel (FAME), hydrogen, and sustainable aviation fuel (SAF) from hydrothermal liquefaction (HTL). Growth kinetics were modeled in OpenFOAM–CFD, while combustion/gasification products were determined using Gibbs free energy minimization. Additionally, algal-derived fuels and blends were tested in a two-stroke drone engine, quantifying brake thermal efficiency (BTE), brake specific fuel consumption (BSFC), and emission profiles. For a 10 ha PBR system, ∼1,510 t CO 2 /y was sequestered, replacing ∼ 743 t coal/y, with a ∼ 45 t/y ash reduction. Engine trials revealed that biodiesel–H 2 blends improve BTE by up to + 28 %, reduce BSFC by − 18 %, and lower CO/HC emissions, though NOx increased by ∼ 12 %. The integrated modeling and experimental framework demonstrates that CO 2 -to-algae-to-fuel pathways are both environmentally and operationally viable for UAV-scale propulsion applications.