“Why Algae” tells the story of why we believe the tiny aquatic microorganisms, known as algae, have such strong commercial potential. This section includes:
The Growing Global Algae Problem
Reducing Dependence on Arable Land for Biomass Farming
Bio-products, Not Biofuels.
Algae—the smallest and simplest forms of aquatic plants—are remarkable organisms with seemingly endless potential. The term algae may be used to include both green algae and their evolutionary predecessor, cyanobacteria. Cyanobacteria are the earliest form of photosynthetic organisms, which, along with algae, are responsible for approximately 70% of the oxygen produced on the planet.
Alga may be a single-cell organism that measures only a micrometer in size, or may be multicellular and grow as big as 45 meters (48 feet) in length. i
As one of the earliest known forms of eukaryotic life and simplest forms of modern plants, algae are likely the evolutionary ancestors of all plants. From these humble beginnings, algae have grown and diversified to encompass an estimated 72,500 species, which can be found anywhere from the hottest deserts to the coldest oceans.
As photosynthetic organisms, algae utilize CO2, sunlight, water and inorganic nutrients, like nitrogen and phosphorus, to grow. When excessive nutrients are available—from sources such as agricultural run-off and water treatment facilities—algae can aggressively expand their population size, doubling their biomass in less than a day. During these high growth events, algae may generate what are called “blooms” that can become destructive to the environment.
Algae are composed of protein, carbohydrates and lipids, and these fractions of the biomass can be extracted and used for a variety of applications. The immense biodiversity of algae mean they have several advantages over traditional crops, including:
- independence from arable land to grow
- their capacity to create biomass rich in protein, carbohydrates, and lipids
- their high growth rates
- a long growing season in warm climates, and
- their capacity to create high value products servicing a number of markets including foods, fuels, nutraceuticals, and plastics
The Growing Global Algae Problem
When realizing the potential market impact of algae, it is also important to recognize the major environmental detriments wild algae have caused. Generally, algae work with other parts of the ecosystem to create environmental balance—but in the case of blooms, excessive nutrient concentrations from human or non-human causes can produce explosions of the algal population.
When these population explosions occur, the algae may oxygen starve the water. This causes other organisms in the ecosystem to die off in large masses called “dead zones.” In some more severe cases, they may produce potent toxins that damage other organisms in the ecosystem. Blooms have become especially prevalent in the last decade as global temperature rises have created optimal water temperatures for algae to proliferate.
Blooms have also been impacted by increase in human population sizes, and from activities like overfishing, which have increased the nutrient loading of waterways. These blooms can have far reaching impacts that may affect regional economies and ecosystems. While algae blooms are not a new problem, the occurrence and severity of blooms have become substantially worse since the early 21st century.
Since 2005, the Baltic Sea has experienced massive seasonal algal blooms, once generating the largest recorded “dead zone” in history. ii
An occurrence known as “red tides” has also increased in frequency and intensity all around the Americas, including the Gulf of Mexico, and the Californian and Canadian coastal areas.
China’s Yellow Sea—plagued by blooms for years—hosted the largest ever recorded bloom in 2013, and battles seasonal bloom issues. iii
However, algal bloom issues are not just isolated to salt water sources. They often impact some major sources of drinking water as well. Lake Erie has recently seen several major blooms in the shallower (and therefore more susceptible) southwestern part of the lake. In 2011, Lake Erie saw the largest bloom for that region—three times larger than any bloom that had ever existed there previously—affect the drinkability of water for weeks. iv
China’s Lake Taihu, a once scenic lake and popular vacation spot in the 1980s, has been plagued by yearly blooms since the late 1990s. In 2007, algal blooms caused 2 million people to go without water for several weeks.
As a result, China invested $155 million into remediating problems in the lake.v
These blooms also can have deleterious effects on not just the environments in which they occur, but also on industries related to those environments, such as:
- Food markets primarily in fishing and shellfish farming,
- Tourism and recreation industries
They can also cause human health problems; creating demand for national aid in drinking water and other supplies; and increase poverty levels in regions affected, thus increasing dependence on social services, and subsequently, tax strains on national economies. vi
While the vast proliferation of algal bloom left untouched within local ecologies wreak havoc on the environment and the municipalities that manage them, technologies exist to help mitigate these harmful effects. It is possible to turn negative environmental impacts into positive, sustainable market opportunities that benefit the environment, human health, and the economy.
Reducing Dependence on Arable Land for Biomass Farming
As of 2004, the International Energy Agency reported 14 million hectares (about 35 million acres) of cropland were converted for biofuels production.7 These crop field conversions increase prices for agricultural commodities. Thus, with an increase in the sale price of these products, it provides further incentives for farmers and land owners to convert more rainforests into agricultural land. This promotes the destruction of forests and other natural ecosystems in many developing countries.
“It is possible to turn negative environmental impacts into positive, sustainable market opportunities that benefit the environment, human health, and the economy.”
One of the most common crops for biofuels production is corn. While the FAO reports that growing corn can remove 1.8 metric tons of carbon dioxide per hectare per year, it also reports that clearing forests for farmland can generate 600 to 1,000 metric tons of carbon dioxide per hectare.8 This is because the slash and burn techniques used by the developing world in clearing land generate harmful greenhouse gases, which the Intercontinental Panel on Climate Change reports account for 20% of all human-caused greenhouse gas emissions.9 It may take up to 500 years to sequester the carbon dioxide created in the conversion of land into croplands to accommodate biofuels and bio-products production (excluding the carbon dioxide created from biofuel usage).
Algae are not limited by the same constraints as terrestrial crops, and can offer substantial benefits that aid sustainable production methods. While efficient algae production is primarily limited to warmer temperatures, it does not require the use of arable land. In fact, much of the current algae production exist in rural, arid environments, due to the lack of sun obscuring vegetation, and the lower risk of pond contamination from wild algal species. Furthermore, since the strains of algae targeted for industrial applications are not the same as those used for food, and because they have less stringent growth restrictions, they are not likely to compete for land with food production or affect food prices in any way.
Algae may also aid the process of cleaning water from both the environment and human waste sources. In conventional wastewater treatment processes, the clean water that leaves the treatment facilities may contain large amounts of natural biological molecules like nitrates, nitrites, ammonia, and phosphates. These are generally considered harmless, but can cause very rapid growth of bacteria, algae, and other aquatic plants. If the nutrients are high enough in concentration, they can cause blooms that have negative environmental effects. Algae production may be added to these existing water treatment operations to provide a final polishing step, or it can be tied to large ecosystems, such as lakes, to help correct long-term contamination effects. In both cases, algae may be farmed on non-arable land to help correct environmental contamination issues that spur from industrial processes or population density. Algae farming is therefore a promising alternative to conventional biomass or biofuel farming techniques.
Bio-products, Not Biofuels
Using algae to make consumer products is not a new idea. Due to their high protein and healthy pigment content, algae are widely used today as a health food supplement. As a food commodity, algae have been used by some of the world’s earliest civilizations in warmer climates throughout Central and South America, Africa, and Asia. More recently, however, algae have come into focus for their innovative uses in industry.
Algae were researched for natural gas production as early as the 1950s. After the 1980s fuel crisis, algae were targeted for their oil producing potential. Since then, a number of companies were founded around the concept of using algae for fuels; but over the past 20 years several large limitations have been realized. The most important of these limitations is the narrow list of oil-producing strains of algae. Strain selection and specificity add cost (as added measures must be taken to eliminate wild species contamination risk), and limits the means of algae production. Furthermore, the oil production process often requires the algae to undergo certain stressors. Stressing the algae complicates the process by inhibiting their growth, thereby limiting their oil production potential. Finally, oil or other fuel produced from algae, requires an extra extraction process to get the targeted compound. While this process is, to some extent, advantageous compared to traditional crude oil production, it is also very costly and limiting in its scope.
Alternatively, when algae can be used in a non-strain specific way without any extraction processes, the potential market impact is significant. In the case of harvesting algae for its biomass, you can target a number of different sources for harvesting algae, including unfarmed sources. Since the whole biomass is used and strain specificity is not an issue, harvesting operations can be planned in conjunction with environmental clean-up efforts. An algae cultivation process for biomass production might include algae for animal feed, anaerobic digestion, or bio-plastics.
For bio-plastics, algae’s high protein content (as high as 65% of the dried biomass in some cases) is particularly attractive, because it makes them naturally capable of behaving like a polymer after exposure to heat and pressure. (Since algae naturally tend towards high protein content when nutrients are abundant, and only move towards starch or lipid production when nutrient availability is low, strain specificity is not an issue, and extraction is not required.) Because the production process of algae for plastics is so simple, implementing the practice is economical and sustainable.
The rapid spread of algal blooms across the globe causes great harm to natural ecologies, human health, and the industries that rely heavily on clean waterways. By harvesting non-specific strains of algae from the affected water sources, we may help mitigate the damaging effects caused by the overabundance of algae, while taking advantage of the many industrial benefits algae biomass affords us.