A Turnkey Solution for Rugged Off-Grid IoT
Build off-grid IoT projects faster with the SN1 Solar Node: an IP67-rated, ESP32-C3 development kit with built-in solar charging.
People who have been around a soldering iron for some time know all the tricks they need to design effective and efficient circuits. If more processing power, longer wireless communication range, or more precise sensing is required, they know exactly what to do. But sometimes a new project will come along that throws them for a loop. For example, how do you build an off-grid sensor node that can withstand exposure to the elements? Electronics don’t like rain at all, and they really do like to stay powered up — where to even start?
A lot of effort goes into a design like this, so sometimes the best solution is to take a shortcut. One option is the SN1 Solar Node, which offers everything needed for off-grid, outdoor applications right out of the box. The device comes equipped with a powerful microcontroller and is housed in a weatherproof enclosure. It also has a solar panel to keep its batteries topped off without manual intervention.
Designed by Granz Scientific LLC, the SN1 Solar Node aims to eliminate many of the common hurdles associated with deploying remote IoT systems. At its core is an ESP32-C3 module with a 160 MHz RISC-V processor and integrated 2.4 GHz Wi-Fi and Bluetooth Low Energy. This gives developers plenty of processing power and connectivity for applications like environmental monitoring, smart agriculture, or distributed sensing networks.
The board is housed in an IP67-rated enclosure, meaning it is protected against dust and can withstand immersion in water. The lid-mounted solar panel feeds into an onboard charging system based on a CN3163 charger IC, allowing one or two 18650 lithium-ion batteries to recharge automatically throughout the day. A built-in battery protection circuit and voltage monitoring system further simplify power management, ensuring safe and reliable operation over long periods.
Unlike many fully integrated commercial solutions, however, the SN1 Solar Node doesn’t lock users into a fixed hardware configuration. A prototyping strip-board area is included directly on the PCB, along with access to most of the ESP32-C3’s GPIO pins through a 16-pin header. This makes it easy to add custom sensors or peripherals without needing an entirely separate board. Optional jumpers also allow developers to enable an onboard LED or thermistor for quick testing and basic sensing tasks.
The inclusion of a Texas Instruments TPS63802 buck-boost converter ensures a stable 3.3V supply even as battery voltage fluctuates, while the ESP32-C3’s low-power modes help extend runtime during periods of limited sunlight. A thoughtful addition is the smart power switch, which allows the device to be turned off while still charging from the solar panel.
Out of the box, the SN1 Solar Node comes preloaded with firmware compatible with ESPHome, making it easy to integrate with home automation systems like Home Assistant. For more advanced users, it also supports development via ESP-IDF or the Arduino framework.
By combining weatherproofing, solar power management, and flexible prototyping capabilities into a single package, the SN1 Solar Node offers a practical shortcut for developers looking to bring off-grid IoT ideas to life quickly and reliably. It is currently selling for $49.99 on Tindie.