First, a diagram of the vertECO system was defined including all possible connections, where after a basic version of the system was built and expanded into a laboratory-scale version. Next a robust computing system, made up of an electronic board composed of a micro-controller and peripheric (auxiliary boards) was defined and a dedicated software program was developed (in LabView) to permit a user-friendly interface and allow for easy configuration, capable of monitoring and collecting/transferring water quality and level sensor data, and then responding accordingly via activation of control devices (pumps and valves).
Since the available industrial quality sensors differ in power specifications, it was decided to develop 2 software versions. the first for laboratory use, dubbed the VerEcoLab and based on the Melhaus reaLab 1208LS data acquisition card, and another for commercial use based on an adapted ARMX to 32-bit RISC micro-controller with a reduced pin count and low energy consumption requirements. the latter permits advanced connectivity (Bluetooth, WIFI, ADSL, etc) and integration with the energy harvesting systems (in this case the PMFC technology) and the fully integrated system was implemented, tested and evaluated for functionality and reliability.
A search for potential PMFCs for testing on the vertECO system yielding circa 200 publications with few (around 20%) contributing to furthering the state-of-the-art. Although a search PMFC technology products cast light on one particular producer/supplier, ultimately this product was not made available for testing. Alternative "energy harvesting" options were however also considered including the generation of energy from sources such as photovoltaics, piezoelectrics, MEMS pyroelectric generators, thermo-couplers and radio frequency energy harvesting.
To reasonably compare power consumption of the different devices, the EEMBC® CoreMark™ benchmark was applied to showing that ultimately, the “intuitive” choice in favor of low power did not necessarily yield the longest battery life. A series of tests were conducted to conclude that a 32-bit micro-controller powered by a 240 mAhr CR2032 coin-cell battery and performing at 6 MHz translates into 3.6 million iterations, or 100 hours of life. With energy consumption remaining a particularly critical device parameter, PMFCs were considered a plausible energy harvesting solution for electronics based in UCs at 32bits.
With numerous attempts to acquisition the previously selected PMFC modules proving fruitless, it was decided to manufacture the system “in-house”. Once built, tests and experiments on the then fully implemented system (small-scale modelling) were carried out to verify the correct and consistent functionality of the electronics, and to determine the charge and discharge time. Scaled cross the entire vertECO system, the results permit for a charge of up to 12V per day (calculated on 4x1.2V batteries per vessel = 48 batteries distributed along 12 vessels). Similarly, with 1x9V battery per vessel, the system could attain a total charge of 12 volts every 100 minutes, working between 75% to 95% of the discharge to charge rate of the battery.
The supply chain was analysed for cost optimization potential and the feasibility of inclusion of vertECO into different commercial units. The large and variable number of components and devices from different producers with diverse set-ups suggest two variations of possible supply chains. Firstly, it would be possible to acquire the components from individual suppliers, (suitable for large production numbers due to the higher discounts obtainable on large orders, or secondly, where fewer production numbers are involved, it would be more practical to use specialized industrial distributors to obtain discounts and reduced delivery times. The feasibility of the inclusion of the vertECO system into different commercial units was also considered with reference to architectural design, water treatment facilities, combined water-treatment and renewable energies, and with regards to small to medium-sized industries required to treat grey-water before releasing it back into the environment.
Patent searches for competing publications were carried out in the different areas of application. While the searches raised a large number of related publications, they further suggest that whereas individual system components may be subject to existing intellectual property rights, the system "as a whole sum of the individual parts" is innovative and it would be possible to apply for a patents or utility model.
The project has accordingly delivered the expected results in accordance necessary for the market validation and further exploitation of the vertECO system, culminating in the innovative first fully-automated and sensorized stand-alone plant-based water purification system.
