esp32S3 Mini - Eco friendly humidity and temperature control for low energy drying and greenhouses

This project was initially inspired by the challenge of recreating a solar-powered dehydrator. The boards operate on the principle of differential humidity which provides low energy drying allowing for off-grid solar powered systems.    It is designed to support larger drying systems for lumber but can easily be used for smaller applications, such as herb drying. The system intelligently vents indoor air as soon as it reaches a higher humidity level which allows extraction of moisture continuing the drying process efficiently.  The general therory started as a shed or shop dryer so whenever the outdoor air is more dry than the indoor air we move exterior air indoors.   It can be used to dry herbs,  lumber, gains, garden sheds, shops, etc. 

I designed the sensor connections to ensure maximum versatility and durability, especially considering the varying tolerances of different sensors to high humidity and temperature conditions. The board accommodates inputs for two I2C sensors, two 1-wire sensors, three single-bus sensors like the DHT22, and two hall sensors. This flexibility allows for easy adaptation to varying environmental conditions and sensor requirements.  14 pins including several ADC enabled pins are exposed in the 16 pin connector.

The motor drivers include three multipurpose drivers, tailored to efficiently manage different ventilation needs in large-scale dehumidification. The setup can support a low-power blower for overcast conditions, a high-power blower for sunny days to effectively manage larger volumes of air, and an additional blower for interior air recirculation.  The  bi-directional motor driver along with hall sensors is for control of louvers which helps  minimize parasitic losses.

I plan to use the same boards with different firmware to enable efficient climate control in four-season greenhouses. The larger solution is designed to use multiple of these boards driving multiple layers of blowers to be activated direct from PV power based on available solar electricity.  When used for this purpose the board may be ony partially populated since it really only needs to sense voltage and temperature. 

Key Applications:

1. Solar Heat Redistribution: These boards are programmed to activate robust heat-redistribution blowers in response to abundant solar heat and available solar PV power, playing a crucial role in recharging thermal storage systems.
2. Humidity Regulation: They facilitate outdoor air exchange to maintain ideal humidity levels, incorporating automated control of louvers for optimal environmental conditions.
3. Temperature Control: By managing the exchange of outdoor air, the boards assist in maintaining target interior temperatures, ensuring a consistent and conducive growth environment.
4. Geo-Exchange Fluid Flow Activation: The design optimizes heat exchange through radiators, pivotal in thermal banking systems, by controlling geo-exchange fluid flow and air circulation.
5. Solar-Assisted Drying: Ideal for drying various materials like wood, grain, and herbs, these boards control airflow in sealed solar-heated structures, harnessing solar power for efficient drying processes.
6. Geo-Exchange Innovation: An exciting feature is the integration of a geo-exchange loop, using the earth's natural coolness to dry air in warmer seasons. This approach is particularly effective in regions with cold winters and hot summers, offering a low-cost, environmentally friendly drying solution.

Technical Specifications:

• Connectivity: BLE and WiFi enabled for smart operation.
• Data Logging: Extensive capabilities for precise monitoring.
• Sensor Integration: Multiple humidity and temperature sensors, compatible with various I2C and 1 Wire devices.
• Power Management: Efficient conversion and PWM charging, with capabilities to handle different power sources including solar panels.
• Display and Controls: OLED display for real-time status, along with capacitive buttons for user interface.
• Versatile Motor Drivers: Accommodating various blower and actuator types, including provisions for linear actuators and louvers.
  
  

Open for Collaboration: This design is free to use for personal projects, and I'm open to discussions for commercial licensing or custom software/firmware development. I'm also keen to receive feedback or suggestions for potential enhancements.

Let's collaborate to advance sustainable practices in our communities!