Powering Generic Node, a LoRaWAN® device packed with sensors, using solar energy with Qoitech

TheThings Network

The Things Network Global Team

Posted on 01-03-2022

Generic Node Sensor Edition is a long-range, low-power wireless LoRaWAN® development board packed with sensors to be able to support multiple use cases. Its original design suggests powering Generic Node with two AA batteries in a built-in battery compartment. Such batteries allow Generic Node Sensor Edition to operate without fault for a period of 2+ years. However, some power-hungry use cases require the device to consume more power.

For example:

  • if it transmits frequent uplink messages (e.g. bioacoustics monitoring in the rainforests and oceans),
  • if it continually opens receive windows for downlink messages (e.g. water and gas cut-off valves)
  • and if it requires more external sensors, which is possible with customizable hardware.

For at-home and industrial purposes, this is easy to implement using a battery charger (only for rechargeable batteries). However, if your Generic Node needs to be kept in a place with no access to electricity, other renewable energy sources, such as solar or wind power, can be used for energy harvesting.

Things to consider when designing a solar-powered Generic Node:

  • Estimated power consumption as per use case.
  • Estimated available solar energy at the device location: apart from direct and indirect sunlight, some solar panels can use artificial indoor light sources such as LED, fluorescent, incandescent, and halogen to generate electricity.
  • Solar panel power rating in Watts, Open Circuit Voltage (OCV), and the current-voltage (I-V) curve.
  • Battery storage chemistry, capacity, charge cycles, safety, and price.
  • Voltage rating of the solar charger (linear or MPPT) and the output voltage of the regulator.

A well-designed solar energy charging solution with a regulated output (2.2V - 5.5V) can be used to safely power Generic Node. For example, you can build a simple charger using a solar panel and a solar harvesting circuit (needed to efficiently harvest solar panel energy and store the energy into a lithium battery or lithium-ion capacitor). As energy storage, Lithium-ion capacitors are somewhat more expensive than lithium batteries. They provide more charge cycles (about 50,000) and a wide range of operating temperatures than standard lithium-ion or lithium-polymer batteries. In most cases, lithium-ion capacitors are a great choice over lithium batteries.

Watch the video by Björn Rosqvist from Qoitech on Energy harvesting and batteries for Generic Node to learn more about powering Generic Node Sensor Edition using solar power with a proof of concept:

Build your next LoRaWAN use case using Generic Node. Get Generic Node

LoRaWAN® is a mark used under license from the LoRa Alliance®.