A potential cost effective process to generate biofuel feedstocks may come in the form of using microalgae to treat wastewater and then utilize the biomass as a renewable feedstock for energy production.Municipal, industrial, and food wastewater may serve as an inexpensive feedstock for microalgal growth.Depending on the microalgae, the efficiency of cleaning the wastewater can be extremely high.Our experience with municipal waste at 1000 gallon scale on-site has shown that nitrogen, phosphorus and pathogen removal is accomplished to a level of 99%.The removal of phosphorus from wastewater often requires the use of chemicals, with microalgae systems no chemicals are required.The energy required for algae growth is much less than that used in activated sludge wastewater treatment systems.Microalgae can utilize both ammonia and nitrate as nitrogen sources alleviating the need for a nitrification/denitrification system.The endproduct is a low nutrient, low pathogen, low BOD water which can be further processed to drinking water or be used as irrigation water.The microalgae sludge may be used as a supplement to an anaerobic digestor to produce biogas (methane), or if the microalgae are ultimately nitrogen starved (enhances lipid production), the lipids can be isolated and converted into biodiesel (a drop in fuel).The combination of wastewater treatment and biofuels production can be integrated into a large system to satisfy multiple needs.