Despite the many positive benefits of using algal biofuels, there are many drawbacks to it as well. One of the most pressing dilemmas concerning the usage of algae as energy is the current cost of maintaining and supporting algal colonies. As of 2010, the cost of just one ton of algae happened to be $5,000 which is presently far too expensive for many still developing countries to invest in. Most of this cost is attributed to the equipment required to effectively harvesting algae with improving the extraction of oils and the downstream processing.  (PC3)

 

Despite the conundrum of cost, there are also nutrient and crop protection problems concerning algal growth. Like many other plants and fungi, algae requires the essential light, water, as well as a constant carbon source. However, many species of algae require major nutrients such as phosphorus, nitrogen, iron, and sulfur. Though these species can sequester such nutrients in small scale areas, the needed supplements for a large-scale growth are thought to be exponential and somewhat difficult to gather as the fertilizer needed for these organisms are in part generated from fossil fuels themselves or mined making them nonrenewable. (PC3)

 

Besides the quandary of nutrient supply, there is also the challenge of crop protection to minimize algae death. To prevent death, scientists would need to determine how to overcome the threat of predators, competitors, and/or parasites by creating both open and closed pond systems both of whom produce their own problems such as high capital expense for closed systems or high risk contamination within open systems. Thus, despite the positive factors associated with the growth of algae, there happen to be many setbacks that must be dealt with before usage of this organism as a biofuel and biomass continues onto large scale production (PC3).