Smart Bio Fresh Algae Air Purifier with ESP32 monitoring.
Bio Fresh combines living green algae with low-cost electronics to capture CO2, release oxygen and monitor indoor air quality automatically. Designed for classrooms, labs and eco-friendly homes.
What is the Bio Fresh Algae Air Purifier?
Bio Fresh is a prototype that uses live algae culture in a water tank to improve indoor air quality. Algae naturally absorbs carbon dioxide (CO2) and releases oxygen (O2) through photosynthesis. We enhance this biological process with sensors and an ESP32 microcontroller to monitor the environment in real time.
The system continuously tracks CO2 levels, light intensity, water temperature and tank water level. LED grow lights, controlled using a potentiometer, ensure the algae receives the right amount of light even indoors. All readings can be displayed on a web dashboard or sent to cloud platforms for remote monitoring.
Key Objectives
How the system works from air to data
The purifier has a transparent tank containing water and algae culture (for example, Spirogyra). Air from the room comes in contact with the surface of the tank, and the algae absorbs CO2 while producing oxygen under suitable light conditions.
Typical Sensor Ranges
| Parameter | Typical Range | Purpose |
|---|---|---|
| CO2 (proxy) | 400 – 1200 ppm | Indoor air quality |
| Light (BH1750) | 3000 – 8000 lux | Algae photosynthesis |
| Water Temp | 22 – 30 °C | Algae growth |
| Water Level | Safe / Low | Protect pump & culture |
Values shown are example ranges used for demonstration; actual values can be calibrated depending on the algae species and tank size.
Sensors & Components Used
The design focuses on using easily available and low-cost modules that can be interfaced directly with the ESP32 development board.
Used to measure overall air quality and act as an approximate indicator for CO2 concentration near the algae tank.
Measures the intensity of light falling on the algae tank to ensure there is sufficient light for photosynthesis.
Detects water level inside the algae tank to prevent drying, protect the pump (if used) and keep algae safe.
Monitors the temperature of the algae culture to keep it in the ideal range for growth and photosynthesis.
Main microcontroller that reads all sensor data, controls LEDs and optionally uploads data to a web dashboard or IoT platform.
LED light provides the required spectrum for algae; the potentiometer allows manual brightness control which can also be read by ESP32.
Benefits & Applications
Bio Fresh is not just a science experiment; it is a teaching tool and a starting point for real sustainable air solutions.
Environmental Impact
Educational Value
Technical Highlights
Low-Cost Prototype Design
The project is designed to be affordable for students. Prices vary by country and supplier, so you can adjust the values according to your local electronics market.
| Item | Quantity | Approx. Cost (?) |
|---|---|---|
| ESP32 Development Board | 1 | |
| MQ-135 Gas Sensor | 1 | |
| BH1750 Light Sensor | 1 | |
| HW-828 Water Level Sensor | 1 | |
| DS18B20 Waterproof Sensor | 1 | |
| LED Grow Light + Potentiometer | 1 set | |
| Algae Tank, Tubes & Misc. | 1 set | |
| Total (approx.) | - |
Note: Replace the blank cost fields with your actual component prices from local shops or online stores.
Project Demo & Enquiries
Use this section in your live website to collect feedback or project enquiries from visitors. For now, it is a sample form; you can connect it later to email or Google Sheets.
Spirogyra & Algae Habitat (Info)
Spirogyra is a common green filamentous algae often found in freshwater habitats like ponds, ditches and slow-moving streams. It photosynthesizes actively in the presence of sunlight and clean water.
For this project, a small quantity of Spirogyra can be cultured in a transparent tank with adequate water, light and nutrients. Maintaining a stable temperature and preventing contamination will help keep the algae healthy.
The habitat design demonstrates how even a simple freshwater algae can be used creatively for air purification and environmental education.