Design and Implementation of a Sustainable Automated Hydroponic System

Abstract

This capstone project presents the design and implementation of a sustainable automated hydroponic system intended to reduce manual labor, improve nutrient management, and support resource-efficient urban agriculture. The system addresses common limitations of conventional hydroponic setups, including manual monitoring of pH, electrical conductivity (EC), temperature, and humidity, which often lead to inconsistent crop growth and human error.

The developed solution utilizes a dual-subsystem architecture based on ESP32 microcontrollers. One subsystem manages nutrient preparation and dosing, while the second controls environmental actuators such as ventilation, humidification, lighting, and water circulation. Real-time monitoring is achieved using pH, EC, water temperature, and air temperature/humidity sensors. Automated control logic was implemented to maintain nutrient solution pH between 5.5–6.5, stabilize EC levels, and regulate environmental conditions within optimal ranges for plant growth.

To improve sustainability and affordability, the system was designed using low-cost embedded hardware, relay-based actuation, and custom 3D-printed PETG enclosures. Several engineering iterations were performed, including the addition of active cooling, sequential nutrient dosing, sensor calibration routines, and automatic pump priming to improve system reliability and dosing accuracy.

Experimental validation was conducted using a 30-liter nutrient reservoir and a basil growth cycle. Results demonstrated stable operation with pH maintained within the target range, EC stabilized around 1200 µS/cm, and environmental conditions consistently controlled during integrated testing. The total prototype cost was 160,094 KZT, remaining significantly below the project budget constraint of 300,000 KZT.

The project demonstrates that an ESP32-based hydroponic automation platform can provide an effective, scalable, and economically accessible solution for sustainable food production. Future work includes integrating both subsystems into a unified control architecture, implementing PID-based feedback control, and conducting long-term field validation under real operating conditions.