Introduction
This will be the final blog post of Sustain the World Design Challenge. I really enjoy this challenge and also the conversations that I had with a few folks about this project. Hope to continue some technical and science discussions about this sustainable system. As a summary of this project, I tried to highlight the features of this smart hydroponic system and other alternatives like commercial hydroponic system and Kratky method. I always wanted to build my own hydroponic system, so this was a very good opportunity 
Project Highlight and Comparison
1. This Smart Hydroponic System
This is the block diagram of the system.
Here is how to build a DIY hydroponic system. https://green-scientist.com/2020/05/16/diy-hydroponics-under-10-mins-with-basil/
2. Commercial Smart Hydroponic Systems for comparison
3. Kratky Method (traditional hydroponic system)
A bunch of three-gallon buckets to grow tomatos and peppers. This method is known for many years and you only need to set it up once and that's all.
Here is how to build a Kratky method. https://green-scientist.com/2020/09/13/grow-tomato-indoor-when-air-pollution-is-hazardous-in-oregon/
Here is the summary of the feature sets
| Features | This Smart Hydroponic System | Commercial Hydroponic System |
|---|---|---|
| Light | Yes | Yes |
| Timer | Yes | Yes |
| Water Level Sensor | Yes but broken (new water level sensor is coming) | No |
| Temperature | No - Can be supported but running out of I2C connection | No |
| Humidity | No - can be supported but running out of I2C connection | No |
| Cooling Fan | Yes | No |
| Air Pump | Yes | No |
| Exterior decoration | Bad - Looks like DIY | Good |
| Remote Control | Yes - light, air pump | No |
| Camera | Yes with Real Sense Camera | No |
| CO2 Sensor | Yes | No |
| TDS (Total Dissolved Solid Sensor) | Yes | No |
Conclusion
Thanks very much for Infineon and Element 14 community to give me an opportunity to work on this project. I am still interested in improving this smart hydroponic system in my garage