Thermal Control in Algae Cultivation

A successful algal industry would be transformative in the US. The very high productivity of algae relative to land plants will drive massive job creation in rural areas, provide biofuel and biopolymers to reduce dependence on foreign sources of oil, reduce fertilizer run-off with its corresponding water quality impairment, reduce greenhouse gas emissions, and enable use of currently underutilized land and saline water resources for food and fuel production. Overall, the forty-fold increase in agricultural productivity will result in an economic boon for the US and a sustainable way to meet the world’s growing protein and energy needs. Algae cultivation typically achieves higher productivity in higher solar insulation and in shallower raceways or photobioreactors; however, high water temperature in the raceways or photobioreactors is a major limiting factor in achieving shallow operation during the summer and on warmer, higher humidity days in the spring and fall. The converse is true in the winter, with low overnight temperatures lowering the productivity until the raceway warms up. This project will develop a set of novel technologies to achieve thermal control in shallow raceways or photobioreactors, and demonstrate use of the technologies in shallow, open, outdoor raceways. These technologies will benefit the algae industry and the algae biofuel program by enabling a broader application of shallow open systems used to achieve high productivity, increasing productivity through operation in the optimal temperature range, reducing crashes and bacteria levels from release of extracellular materials, allowing use of a much wider variety algae strains, and providing a pathway for use of new approaches to reduce evaporative water loss.By facilitating a commercial algal biofuel and commercial algal protein industry this project will directly benefit rural communities by creating many high-quality jobs in rural areas through the higher productivity per area and per amount of water used, and through the use of currently underutilized land and water resources. The entire US public will benefit from the economic boon created by much high productivity from land and water resources. The public will also benefit from the environmental benefits of reducing agricultural chemical run-off, reducing water requirements for food and biofuel production, reducing greenhouse gas emissions, and reducing pressure to convert forests or other valuable land resources to food and fuel production.