Projects:2016s1-181 Solar Aquaponics

Project Team

Supervisors

Rastko Zivanovic

Said Al-Sarawi

Group members

Hassan Alabdullah

Kaidi Zou

Project Introduction

Background

The term aquaponics is used for an agriculture system involving the simultaneous cultivation of plants and aquatic animals, such as fish, in a symbiotic environment. Aquaponics systems can be used in outdoor set up or indoor aquaponics greenhouses.

Motivation

Labour and energy usage is the largest cost factor for aquaponics systems. Energy consumption varies largely with the layout and purpose of the system. The project investigates a novel approach of using solar energy to provide electric energy required for sensing and monitoring an aquaponics system.

Project Aim

This project aims to verify the feasibility of using solar PV system to supply the consumption of the aquaponics system and detect how to predict and monitoring the dynamic condition of the system by software and electronic sensors.

System Implementation

The solar aquaponic system model contains three main parts namely solar system, aquaponic system and monitor system.

Solar System

Solar system consists of Mono crystalline PV panel, regulator and backup battery.

Acquaponic System

Aquaponic system is consists of grow bed for plants, fish tank, siphon. Water is done by water pump that pumps water from fish tank to grow bed through biofilter. When water reaches highest level the siphon will drop water to fish tank. Fish will release waste that contains solids and Ammonia (NH3+). Bacteria that colonies on surfaces of the tanks and biofilter will convert Ammonia to Nitrite then Nitrate that is absorbed by plants as organic fertilizer.

Monitor System

The monitor system consists of three electrical sensors which are pH, Ammonia NH3+ and solar irradiation. Monitoring and adjusting these parameters is important and critical. PH level should be within the range 6-7. The ammonia of fish waste should be converted to nitrate that is absorbed by plants as fertilizer.

Solar Aquaponic System Model One

The main parts of the system model were connected to form model one. The measurements are in the correct range comparing with University of Virgin Islands (UVI)system. The solar system supply electrical power to operate water pump and timer circuit. The system was implemented for three months without any shortage in electricity that indicates the PV solar system size is enough to operate the model even in cloudy days using proper battery capacity as storage. The storm of 28th October 2016 was a good test for system model one. The wither was rainy and windy for three days but the system model was working properly using the battery as power source. The monitor system measures critical parameters which are water pH, Ammonia and solar irradiation. The measurements of the monitor system help to ensure that the solar aquaponic model is working properly and adjustments will be applied as needed. Another good indication is healthy plants and fish growing over time for three months. The plants were raised are Strawberry, Mint and Zucchini. The fish raised are Golden fish and Silver perch.

Software Model Simulation

Model explanation

The new model add silver perch in fish type, add strawberry, mint, and zucchini in plant type, which are new introduced in the new aquaponic model. Temperature are added as one factors to determine the simulation outcome. pH changes simulation was added. Water flow and Energy flow were adjusted to satisfy the new grow media and NFT combination model. The solar radiance data was re-written base on the sensor-detected data. The following data and chart do not reflect the real amount or number, but the ratio between each factor.

Fish and plants simulation

The fish and plants simulation reflects the relationship between each index, by choosing different fish type and plant type we could get the simulation graphic. The data used in this model is from the research of UVI [8].

The silver perch growth model was set based on (Silver perch - aquaculture prospects 2016): The optimum temperature range for commercial production is 23-28° C. In a good growing climate, silver perch can be raised to market size of 600-800g in around 18 months. 5×〖(1+x)〗^545=700

Figure 1. Fish simulation

The plants simulation is designed to reflect the plant weight change in growing bed and plant harvest weight under the influence of nitrate concentration from nitric cycle; also, the curve for daily adding water will reflect as water consumption will affect the water circulating system. The water needs to be adding daily mainly due to evaporation and water leakage when circulating

Figure 2. plant simulation

pH simulation

pH is an important index, as the fish and plants could only survive in a proper range of pH. The pH changing simulation is set based on previous study and my understanding of the system. Adding water would increase the pH, as the Adelaide water pH is slightly higher than 7, while fish waste and the feed is under 7, so it slightly decrease pH.

Figure 3. pH change simulation.PNG

Water cycle simulation

The water flow would increase after adding NFT to the model, the fish tank and agriculture area is larger than before, so the evaporation is much more, the water level should keep balance ideally, hence the daily adding water should increase to keep the water level balance.

Figure 4. Water cycle simulation simulation.PNG

Conclusion

Results and Analysis

The plants are growing well, and the strawberry harvest several fruits, and zucchini have flowers. The silver perch and gold fish are growing well, but due to the silver perch is added into the system less than 1 months, it cannot compare its weight with the simulation one. However, as simulated by the software model, the silver perch would harvest in April 2018

Future work

Software Model

First, the software model is not able to simulate when two or more types of fishes exist, as well as plant types. I was trying to figure it out, but it was much more complicated than I expected. Second, the model was set based on UVI’s research and our understanding of solar aquaponics, it have not been proofed whether it could work well in real solar aquaponics environment, it should be verified by experiments before it could be used. Finally, due to the limitation of our knowledge and time, it may have some defects in modelling the system I would apology for that.

System implementation =

First, the software model is not able to simulate when two or more types of fishes exist, as well as plant types. I was trying to figure it out, but it was much more complicated than I expected. Second, the model was set based on UVI’s research and our understanding of solar aquaponics, it have not been proofed whether it could work well in real solar aquaponics environment, it should be verified by experiments before it could be used. Finally, due to the limitation of our knowledge and time, it may have some defects in modelling the system I would apology for that.

Reference

[1]Love, DC, Fry, JP, Genello, L, Hill, ES, Frederick, JA, Li, X & Semmens, K 2014, ‘An international survey of aquaponics practitioners’, PloS one, Vol.9(7), pp.e102662.

[2] Fox, Bradley K.; Howerton, Robert; Tamaru, Clyde. "Construction of Automatic Bell Siphons for Backyard Aquaponic Systems" (PDF). University of Hawaiʻi at Mānoa Department of Molecular Biosciences and Bioengineering. Retrieved 12 March 2013

[3] Rakocy, James E. "Aquaculture – Aquaponic Systems". University of the Virgin Islands Agricultural Experiment Station. Archived from the original on 4 March 2013. Retrieved 11 March 2013.)

[4]Mengna X & Haokun W, proposal seminar ppt.

[5] Software documentation on the company's official website.

[6]Martins, C.I.M, Eding, E.H, Verdegem, M.C.J, Heinsbroek, L.T.N, Schneider, O, Blancheton, J.P, d’Orbcastel, E, Roque & Verreth, J.A.J 2010, ‘New developments in recirculating aquaculture systems in Europe: A perspective on environmental sustainability’, Aquacultural Engineering, Vol.43, no.3, pp.83-93.

[7]Laidlaw, J & Magee, L 2014, ‘Towards urban food sovereignty: the trials and tribulations of community-based aquaponics enterprises in Milwaukee and Melbourne’, Local Environment, pp.1-18, < http://dx.doi.org/10.1080/13549839.2014.986716>.

[8] G. Andreas and J. Ranka, “Aquaponic Systems: Nutrient recycling from fish wastewater by vegetable production,” Desalination, vol. 246, pp. 147–156, 2009

[9] Axelrod, H.R.; Vorderwinkler, W. (1984). Goldfish and koi in your home. T.F.H. Publications. ISBN 0-86622-041-0.)

[10]Lennard, W 2012, ‘Aquaponic System Design Parameters: Fish to plantratios (fish to plant ratios)’, Aquaponic Fact Sheet Series, Aquaponic Solution, pp.1-11, < http://www.aquaponic.com.au/Water%20Chemistry.pdf>.

[11]A. Molki (2010). "Dust affects solar-cell efficiency". Physics Education. 45: 456–458. Bibcode:2010PhyEd..45..456M. doi:10.1088/0031-9120/45/5/F03

[12] Electrical Plug/Outlet and Voltage Information for Australia : Adaptelec, International Electrical Specialists 2016, viewed 18 October 2016, <http://www.adaptelec.com/index.php?main_page=document_general_info&products_id=237>.

[13]Solar Panel Tilt Calculator - DIY Solar Kits 2016, viewed 20 October 2016, <http://www.gogreensolar.com/pages/solar-panel-tilt-calculator>.

[14]Chris Andrews, Interpet Publishing (2002) An Interpet Guide to Fancy Goldfish. ISBN 1-902389-64-6

[15] Silver Perch | #1Aquaponics Australia 2016, viewed 20 October 2016, <http://1aquaponics.com.au/products-page/fish_and_fingerlings/silver-perch/>.