5 LoRa Alliance
®
A LoRaWAN environmental sensor
equipped with compact solar panels for
energy harvesting. Solar (photovoltaic)
energy is the most widely used ambient
power source for IoT devices due to its
simplicity and relatively high energy yield,
even under indoor light [8].
The result is that device lifetime is no longer capped by battery capacity. With proper
engineering, an energy-harvesting sensor can operate for 10+ years in the field[10]. In
fact, the limiting factor often becomes the longevity of the electronics or sensor
components themselves, not the power source. This flips the usual concern on its head
– as one industry observer noted, with energy harvesting, the new question becomes
"How long will the electronics last?" instead of "When do we need to replace the
battery?"[11].
Solar-powered LoRaWAN devices have already demonstrated multi-year, continuous
operation in real-world deployments (for example, indoor CO₂ sensors with small solar
panels have run over a decade with zero battery replacements[12]). These successes
prove that ambient light can effectively fuel IoT endpoints indefinitely, as long as the
power demands are engineered to stay within the harvested supply.
Lower TCO and Extended Infrastructure Value
When energy harvesting meets a mature IoT ecosystem, the economics change
completely. When a company or city deploys a LoRaWAN network of solar-powered
sensors, they are investing in equipment that will serve them for a decade or more with
minimal upkeep. This dramatically improves the return on investment (ROI) calculus.
