An Aquatic Approach: How Aquaculture Can Provide Environmentally Sound Clean Energy
While agriculture waste is a potential solution to finding a clean energy source, there are still problems which must be considered, primarily the disruption of the nutrient cycle and the removal of key nutrients from the soils relied on for food production. However, there is another type of agriculture which could provide the necessary biomass for fuel without taking over the limited space we have for food production: aquaculture. Nutrients are a product of aquaculture facilities, and when combined with farm runoff and organic wastes, aquatic ecosystems have acquired toxic levels. This abundance of nutrients can lead to severe problems such as algal blooms and eutrophication, which are harmful to both human and ecosystem health. By removing some of these nutrients in the form of algae and other aquatic plants, the chances of experiencing these problems is greatly diminished, and there is biomass available for energy production!
With available fossil fuel supplies depleting rapidly, it is time to turn to the original source of energy: the plant itself. Algae and other aquatic plants have rapid growth rates, remove carbon dioxide from the atmosphere, and release oxygen (Chan 1993). Farmed algae can be grown for many different reasons, including nutrition or aquaculture feeds, but it can also be a reliable source of energy by producing biofuels and ethanol (Food and Agriculture Organization). One of the most advantageous methods of aquaculture is developing an integrated system where plants and animals feed necessary nutrients to each other, which helps eliminate waste and grow better stocks of both (Chan 1993).
Like other aquatic resources, algae have been historically harvested from the wild. However, aquaculture is continuing to grow at a steady rate (Warwick 2016). Taiwan was one of the first countries to successfully develop an aquaculture farm, where Gracilaria is grown alongside fish and shrimp (van deer Meer 1983). Due to the limited agriculture space an island country can provide, Taiwan began looking towards algae as a source of biofuels (Kao 2008). Learning good techniques to farm, instead of capture, these energy sources will allow sustainability and availability to be maintained, and diminish negative effects on the environment (van deer Meer 1983). Learning about an artificial aquatic ecosystem that could provide biomass in healthy quantities is important, and learning when and how to properly remove and recycle nutrients can lead to increased food and energy, in both the aquatic and terrestrial terrain (Chan 1993).
In Abu Dhabi, a small scale integrated system was opened to figure out the technical aspects behind the science of sustainable aquaculture (Warwick 2016). The goal of the facility is to use the nutrient rich water in aquaculture systems and filter it through halophytes, which will create biomass to be converted into biofuel, while also cleaning the wastewater before it is released (Warwick 2016).
There are many incentives to developing biomass through farmed aquatic plants. One of the most important factors to consider is that utilizing aquatic ecosystems for energy crops does not take land which could otherwise be used for food crops (Kao 2008, Warwick 2016). In addition to utilizing a different space than food crops, algae grow faster than any land based energy crop (Kao 2008). This means that more energy can be produced solely on biofuel, diminishing the reliance on carbon. Algae also take in carbon dioxide, so in Taiwan the energy industry looks toward big industries to redirect their carbon emissions to feed the crops (Kao 2008). This could lead to a reduction of overall carbon emissions if globally initiated.
The key to a successful aquaculture energy system comes from developing technologies which can financially sustain it. However, there are many benefits which may outweigh the costs. Plants grown for biomass can help to alleviate the reliance society has on fossil fuels while also removing CO2 from the atmosphere, making it a far more stable energy source (Kao 2008). The plants grown can also help to filter waste water in order to prevent toxic levels of nutrients entering aquatic ecosystems (Warwick 2016). Many ancient practices that have been used in China and Taiwan have discovered ways to balance the plant material with the primary product (fish or seafood) in order to create an independently functioning system (Chan 1993, van der Meer 1983). By creating these sustainable artificial environments, it is possible to provide biomass fuel without further harming the environment through nutrient removal or ecosystem destruction.
- Chan, G. (1993). Aquaculture, Ecological Engineering: Lessons from China. Ambio, 22(7), 491-494.
- Food and Agriculture Organization of the United Nations. Aquatic Biofuels: Knowledge. http://www.fao.org/bioenergy/aquaticbiofuels/knowledge/en/
- Kao, C. (2008). Development of Biomass Energy in Taiwan: Current Status and Prospects. 4th Iasme/Wseas International Conference on Energy, Environment, Ecosystems and Sustainable Development (EEESD’08). 126-129.