Carbon Dioxide Capture by Engineering a Self-Sustained Coral Reef Park with Renewable Energy Paulane C. Quiray ,Umar Raja, David Athey, Tabatha Savage, Matthew Egeland and Dr. Tsung-chow Su, Department of Ocean and Mechanical Engineering FAU and Hiroko Suzuki, Department of Bioengineering, University of Tokushima, Japan

Method Results Discussion Is it possible to engineer a coral reef park that is self-sustained with • We investigated the Biorock ® method of W. Hibertz Using the ocean bottom current as an on-site • It is well known that while coral reefs remove carbon and T.J. Goreau, which uses low voltage direct currents Renewable Energy Source. We looked at both the from the ocean, they are, in fact a source of to the renewable energy on site? CO2 (above 1.2 Volts) to grow solid limestone mineral on frontal kinetic energy flux and compared it with planform atmosphere. This is because the ocean is a pH conductive substrates. This low current also prevents kinetic energy flux. The planform kinetic energy flux buffered system in which electrical charge is Will it enhance bio-diversity, provide rusting on the steel substrates. The Biorock material (Pvert) is of an order of magnitude higher conserved. For every atom of bicarbonate in sea coastal protection, promote tourism, could be 3 times stronger than cement if grown slowly. water that is converted to carbonate and deposited as Its strength increases with age, and the material is self- P C- . U and have a positive effect on Vert planform limestone, one molecule of bicarbonate is converted to repairing. There is no limit to the size or shape of carbonic acid and then to CO2 (released to climate change? Biorock structures; they could be grown to be hundreds . , sea water density atmosphere) , park area of miles long. Aplanform U, ocean current speed • In our engineered coral reef, we introduce electrons to Introduction , turbulence velocity fluctionation u’ (streamwise), and w’ (wall-normal) and ensemble average <..> the process of forming limestone. Therefore the conservation of electric charge will not require the • A coral reef is a natural wonder, providing bio- Modeling the planform flux with basic theory of release of CO2 to the atmosphere. The engineered diversity, enhanced beach protection, and serving as a turbulence; coral reef sequestration of CO2 may be possible. tourist attraction. However coral reefs can be  . 3 Pvert / Aplanform damaged by ocean acidification, coral bleaching and • If we scale up the coral reef park to 1000km by destructive fishing. There are several protective Assuming, .   3, U= 0.5 m/s, the flow energy flux 1000km, then 2.3 x 1012 kg(C)/year removal may be measures in progress through monitoring and 2 through the top of the coral reef park is about 14 W/m . achieved, corresponding to about 28% of CO2 flux to restoration in its decline. Therefore, it is desirable to the atmosphere from fossil fuel burning world wide in consider engineering a self-sustained coral reef park For a 10 km by 10 km park, this translates into a 2009. Correspondingly, a significant amount of CaCO3 to complement its natural processes in order to 1.4 x 109 W of flow power. formation will result, specifically 1.5 x 1010 tonne. prevent or reverse its loss. Schematic of the Biorock method Through the deployment of an array of Mamikon Conclusion spinners, and assuming that 10% of flow power is It was found that it is possible to engineer a coral reef • To provide an energy source, we investigated the captured and converted to electricity, the coral reef park park that is self-sustained with renewable energy. The potential of a Mamikon spinner, which is a turbine with will receive current threats of ocean acidification, coral bleaching continuously folded one piece blade uniquely suitable 1.4 x 1 08 W of power. for underwater applications. The spinner is also and destructive fishing are harming the current stock of coral reefs. This method to generate self-sustained attractive in its art form and can be deployed on a large This amount of power equates to 15 (Joule) or 4.40 x 10 J coral reefs has the possibility to enhance bio-diversity, scale. This spinner can utilize the flow of energy of 34 (electron volts). And, at , this amounts 2.75 x 10 eV 1.2 V provide coastal protection, promote tourism and have a ocean’s bottom current to generate sufficient electricity to 2.3 x 1034 electrons, generated annually. to provide self-sustained growth of a coral reef park. positive effect on climate change with renewable energy on-site. With the chemical reactions for formation of b carbonic acid: H2O + CO2 H2CO3 , 2+ b References and limestone: Ca + H2CO3 + 2 e H2 + CaCO3 , 1. Conservation of Coral Reefs through Active Restoration Measures: Recent each two electrons will take one CO2 molecules to Approaches and Last Decade Prograss; Envron.Sci.Technol., 2005, 39 (12), Flynn Reef produce one molecule of CaCO3 (limestone). pp 4333-4342 2. Biorock Inc.; Hilberz, W.H. and Goreau, T.J. 1996. Method of Enhancing the Growth of Aquatic Organisms, and Structures Creadted Thereby, US Patent 10 As a result, about 1.9 x 10 moles of CaCO3 forms in the No. 5543034, US Patent Office (14pp) 10 3. Mamikon Spinner Patent Publication No. US 6524073 B2 (2003), Application Decoration of Caltech campus Flow Energy coral reef park. 1.9 x 10 moles of CO2 is equivalent to 2.3 x 8 No. US09/945453 (2001) 10 kg(C)/year. 4. Su, J. T.; Su, T.-C.; Bingham, C.; Kellier, L., On N-fold Propellers and Turbines • The Mamikon spinner is highly durable, produces less American Physical Society, 54th Annual Meeting of the Division of Fluid noise, and is especially bio-creature friendly. Images Dynamics November 18 - 20, 2001 San Diego, California Meeting ID: DFD01, below show water channel testing with fish easily abstract #FE.007 5. Whittlesey R.W., Liska S.C., Dabiri J.O. (2010) “Fish Schooling as a Basis for gliding through the rotating turbine. Vertical-Axis Wind Turbine Farm Design” Bioinspiration and Biomimetrics”, 5:035005. 6. "Flynn Reef." Web. 22 Mar 2011. http://upload.wikimedia.org/wikipedia/commons/2/2e/Coral_Outcrop_Flynn_R eef.jpg 7. "Great Barrier Reef." Web. 22 Mar 2011. http://completeaquarium.blogspot.com/2010_08_01_archive.html. 8. "Biorock Method." Web. 22 Mar 2011. http://www.biorock- workshop.org/biorock/what-is-biorock.html. Great Barrier Reef 9. "Mamikon Spinner." Web. 22 Mar 2011. For example, “Barnacle Reef” Ihuru in the Maldives. Restored http://www.its.caltech.edu/~mamikon/Chips.html. Bio- Creature friendly Mamikon spinner 10. "Barnacle Reef." Web. 22 Mar 2011. . Undergraduate Research Symposium, April 6, 2012