Biofuel from microalgae has significant potential, but the economics of production are still not on par with fossil fuels. One stage of production commonly cited as requiring improvement is harvesting the microalgae from dilute culture solutions. Flotation has emerged as a promising harvesting method that avoids the high energy costs of methods such as centrifugation, but requires the addition of chemical flocculating agents that add to the cost and can contaminate the biomass. To address this, a novel derivative, heat-aided flocculation, is examined. By potentially using waste heat from industry, flotation can be achieved without addition of chemicals.