10 Commandments of Algae Biofuels
10 Commandments of Algae Biofuels
1. Thou shall put no other feedstocks before algae (unless the feedstock is better)
Algae have a number of benefits from high productivity to not competing with agricultural land which makes them one of the more promising candidate feedstocks for biofuels production.
2. Thou will need land
Vast amounts of land will be required to scale up algae for biofuel production. In 2009, 75 million acres of soybeans, and 79 million acres of corn were harvested in the United States (FAO STAT). Soybean and corn are two of the mains sources for biofuel production. So it is necessary to think of the footprint that will be required for algae. While microalgae may be able to use non arable land, it will still require large tracts of land in order to significantly impact our fossil fuel consumption.
3. Thou will need freshwater
It is inevitable that growing algae in inland regions will require freshwater resources. Evaporation alone accounts for a significant loss in open ponds. While algae can inhabit a range of water sources from freshwater, brackish water, wastewater, and saltwater, it is necessary to replace lost water with non saline water. The reason non saline water is needed is that there is an upper limit of salt concentrations that algae can tolerate.
4. Thou shall use cheap nutrients
All algae require some source of nutrients (nitrogen, phosphorus, iron, etc.) in order to survive and create bioproducts like lipids and starch. When the land requirements are put into perspective a large nutrient source is essential. The nutrient source has to be available at a low cost allowing the economics to work in favor of using algae for biofuel production. One cheap source of nutrients could come from wastewater.
5. Thou must have consistent temperature
Temperature is a critical factor in allowing algae to be grown for seasons longer than row crops like soybean and corn. Cooling night temperatures can have a dramatic impact on biomass production. Since the systems for growing algae (ponds) and soybean/corn (soil) are dramatically different it is important to understand the limitations when growing algae on a large scale in ponds.
6. Thou must have sufficient sun
Since most algae are photosynthetic it is critical to locate algae in regions with ample sunlight. (Ignore this if you are growing algae in fermentative systems).
7. Thou must have carbon dioxide
Carbon dioxide is necessary for the algae. Algae can pull carbon dioxide from the air, but it has been proposed to use algae as biological scrubbers consuming emissions from large carbon dioxide emitters such as power plants. It is not likely that algae will consume all of the carbon dioxide provided especially in an open pond growth system, however, the extra carbon dioxide will accelerate the growth of the algae.
8. Thou shall use the optimum strain
With thousands of strains of algae to choose from, it is a critical challenge to screen and identify an algae species which has desirable characteristics for biofuels production.
9. Thou must have a means to harvest
Harvesting is a challenging task with algae accounting for less than 1% of every liter of pond water contains algae. This problem of handling the large volumes of liquid for small amounts of biomass makes it extremely difficult to find a cost effective harvesting strategy.
10. Thou must have a cost effective extraction method
Extraction is another critical engineering challenge that must be addressed. Most biofuel crops are dry which allows for a number of extraction methods to be utilized. Drying algae will either be very energy intensive or a limiting factor to crop turnaround time therefore creating a bottleneck.
Algae have a number of benefits from high productivity to not competing with agricultural land which makes them one of the more promising candidate feedstocks for biofuels production.
2. Thou will need land
Vast amounts of land will be required to scale up algae for biofuel production. In 2009, 75 million acres of soybeans, and 79 million acres of corn were harvested in the United States (FAO STAT). Soybean and corn are two of the mains sources for biofuel production. So it is necessary to think of the footprint that will be required for algae. While microalgae may be able to use non arable land, it will still require large tracts of land in order to significantly impact our fossil fuel consumption.
3. Thou will need freshwater
It is inevitable that growing algae in inland regions will require freshwater resources. Evaporation alone accounts for a significant loss in open ponds. While algae can inhabit a range of water sources from freshwater, brackish water, wastewater, and saltwater, it is necessary to replace lost water with non saline water. The reason non saline water is needed is that there is an upper limit of salt concentrations that algae can tolerate.
4. Thou shall use cheap nutrients
All algae require some source of nutrients (nitrogen, phosphorus, iron, etc.) in order to survive and create bioproducts like lipids and starch. When the land requirements are put into perspective a large nutrient source is essential. The nutrient source has to be available at a low cost allowing the economics to work in favor of using algae for biofuel production. One cheap source of nutrients could come from wastewater.
5. Thou must have consistent temperature
Temperature is a critical factor in allowing algae to be grown for seasons longer than row crops like soybean and corn. Cooling night temperatures can have a dramatic impact on biomass production. Since the systems for growing algae (ponds) and soybean/corn (soil) are dramatically different it is important to understand the limitations when growing algae on a large scale in ponds.
6. Thou must have sufficient sun
Since most algae are photosynthetic it is critical to locate algae in regions with ample sunlight. (Ignore this if you are growing algae in fermentative systems).
7. Thou must have carbon dioxide
Carbon dioxide is necessary for the algae. Algae can pull carbon dioxide from the air, but it has been proposed to use algae as biological scrubbers consuming emissions from large carbon dioxide emitters such as power plants. It is not likely that algae will consume all of the carbon dioxide provided especially in an open pond growth system, however, the extra carbon dioxide will accelerate the growth of the algae.
8. Thou shall use the optimum strain
With thousands of strains of algae to choose from, it is a critical challenge to screen and identify an algae species which has desirable characteristics for biofuels production.
9. Thou must have a means to harvest
Harvesting is a challenging task with algae accounting for less than 1% of every liter of pond water contains algae. This problem of handling the large volumes of liquid for small amounts of biomass makes it extremely difficult to find a cost effective harvesting strategy.
10. Thou must have a cost effective extraction method
Extraction is another critical engineering challenge that must be addressed. Most biofuel crops are dry which allows for a number of extraction methods to be utilized. Drying algae will either be very energy intensive or a limiting factor to crop turnaround time therefore creating a bottleneck.
Judgment Day
Algae based biofuel judgment day will be determined if it is cost competitive with fossil fuels and has a favorable life cycle analysis (LCA) compared to other biofuels. It is absolutely critical that fuel from algae be consistent and meet the appropriate fuel standards set forth for biofuels production.
With algae meeting the above 10 Commandments of Algae Biofuels, and succeeding in achieving LCA and fuel quality standards, we will have a fuel that serves as a plug and play alternative with most of our current fuel infrastructure.
With algae meeting the above 10 Commandments of Algae Biofuels, and succeeding in achieving LCA and fuel quality standards, we will have a fuel that serves as a plug and play alternative with most of our current fuel infrastructure.
