Solar Powered PV PI HAT Enables 24/7 Off-Grid Operation for Raspberry Pi

PV PI Solar HAT for Raspberry PI. Images used courtesy of  Kickstarter

The PV PI is an off-grid solar power manager HAT designed to run Raspberry Pi or any other 5V SBCs 24/7 using a 12V LiFePO4 battery and solar. Developed by AutoEcology, it integrates true MPPT charging, smart power automation, and plug-and-play connectivity to simplify long-term solar operations.

The board is built around a Texas Instruments’ BQ25756 charge controller and an STM32F103 MCU handling MPPT tracking, power monitoring, RTC wake scheduling, watchdog-based cycling, and battery-safe reboot logic. It provides a regulated 5V output via a high-current buck/boost converter, XT30 solar/battery connectors, UART communication with PySerial, external 5V and UART breakouts, and a stackable 40-pin header. These features make this device suitable for solar IoT nodes, off-grid Raspberry Pi projects, environmental logging stations, small autonomous robotics, and remote sensor installations requiring 24/7 uptime.

PV PI Solar HAT Hardware Overview. Images used courtesy of  Kickstarter

PV PI Specifications:

• Supported SBCs: Raspberry Pi, Orange Pi, Banana Pi, NVIDIA Jetson (selected 5V models)
• Main MCU: STMicroelectronics STM32F103 (Arm Cortex-M3 @ 72 MHz)
• Charge Controller: TI BQ25756 bidirectional buck-boost charger, MPPT-enabled, 1–14 cell support
• Power Input (Solar): 8V to 55V DC via XT30 connector
• Battery Support: 12V LiFePO₄ packs, XT30 input
• Charging Type: True MPPT with automatic MPP detection
• Charging Current: Up to 10A
• Output Power: Regulated 5V / 8A supply for SBC + peripherals
• Communication Interface: RS-232 serial (UART) for monitoring and control via Python/PySerial
• Power Management:
  • Configurable 5V cutoff during idle periods
  • Automatic restart at safe voltage thresholds
  • Watchdog-based power cycling
  • RTC with backup battery for timed wake events
• Monitoring: Real-time voltage and current telemetry over UART
• Connectors: Dual XT30 ports (solar and battery), stackable 40-pin GPIO header
• Additional Features: 5V and UART breakout headers, onboard RTC backup power
• Form Factor: Raspberry Pi HAT-compatible footprint

PV Pi with NVIDIA Jetson Development board. Images used courtesy of  Kickstarter

The PV Pi HAT uses a basic UART interface and works with any SBC via Python and PySerial, with no custom drivers. It supports monitoring, power control, and wake-up settings. Documentation and example scripts will be available before the March 2026 shipment, though no exact date is given.

The Raspberry Pi MPPT solar charging kit is now available on Kickstarter, with shipments expected in March 2026. Pricing starts at AU$99 (about US$65) for one unit, or AU$267 (about US$174) for a discounted three-pack. There are other bundle options available on the website.

Images used courtesy of Luke Ditria.