Investigating Life

investigating life

Given that petroleum is derived naturally from green algae, can humans use green algae to produce oil commercially?

Scientists are developing new methods for growing green algae for the production of biofuels (fuels produced directly from living organisms, such as biodiesel). Some species of green algae can produce up to 60 percent of their dry weight in oil. So biofuels can certainly be produced from green algae, although the process is not yet commercially viable. Like conventional fossil fuels, biofuels release carbon dioxide into the atmosphere when burned. In the production of biofuels, however, algae remove carbon dioxide from the atmosphere, so the use of these fuels is more sustainable, and results in less accumulation of CO2 in the atmosphere over time, than the use of fossil fuels.

Future directions

The primary commercial limitations to growing algae for biofuels include the need to establish efficient growing facilities, water needs, costs of fertilizers, costs and difficulties associated with harvest and refining, and labor expenses. As we explored in Investigating Life: Can Chlorella Algae Be Grown in Municipal Sewage Wastewater for Biofuel Production? considerable research is being conducted on ways to reduce these costs, such as growing algae for biofuels in municipal wastewater. Many new methods for growing and harvesting algae are being developed (Figure 27.19). Once some of the technical difficulties have been overcome, it is possible that commercial production of biofuels from algae will provide a significant source of energy for humans.

image
Figure 27.19 Biodiesel from Algae In this algal cultivation system for biofuel production, algae are grown in tubes of clear plastic.