mechanical

PURE LiFe: a portable solar generator (college capstone)

Back in college, a team of four of us — me, Michael Moser, Frank Pocino, and Jesse Saylor — built PURE LiFe (Portable User-friendly Renewable Energy Lithium-iron phosphate), a solar-powered generator, for the WERC International Environmental Design Contest at New Mexico State University. The contest’s “Internet of Science and Engineering” division asked for a self-contained device that could be deployed anywhere, run on renewable/harvested energy, and report data over the internet.

The idea

Swap a gas generator for a solar one: charge a battery bank off a foldable solar panel, invert it to standard household AC, and monitor the whole system remotely instead of just eyeballing a gas gauge.

Full system: Pelican case battery bank next to the foldable solar panel, set up outdoors

What we built

Everything lived in a rugged, one-person-portable Pelican case:

  • 12V / 50Ah LiFePO4 battery bank
  • 80-watt foldable solar panel through a 30A MPPT charge controller
  • 300W inverter (110VAC + USB outputs)
  • Arduino Mega with three current sensors tracking generation, consumption, and battery state
  • HC06 Bluetooth module feeding a companion Android app
  • A 2.4“ onboard touchscreen for at-a-glance status
  • Custom expansion shield and a 3D-printed housing for the electronics
  • A keyed safety switch and other redundant safety features

Inside the case: 1. Bluetooth radio, 2. MPPT solar charge controller, 3. data collection microcontroller

Live and historical power data flowed from the Arduino to the Android app over Bluetooth, and from there up to PVOutput.org for logging and analysis — so you could check charge state and generation history without opening the case.

System diagram: solar panel to charging circuit to battery bank to inverter, with sensor data flowing through the microcontroller and Bluetooth radio to a phone and PVOutput

The whole thing was light enough to carry in one trip:

Carrying the case and folded solar panel by hand

Why it mattered

Zero emissions, no fuel, no maintenance, and enough capacity off the 50Ah battery for multi-day autonomy depending on load. Good for camping and RV power, field research sites without grid power, emergency backup, or just scoping out whether a bigger solar install would be worth it somewhere.

Sponsored by Bioenno Power and Custom Circuit Boards. Full writeup and more photos on the original project site.

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