4 LoRa Alliance
®
As of mid-2024, over 350 million LoRaWAN end nodes (sensors and devices) have
been deployed worldwide, along with nearly 7 million LoRa-equipped gateways[6].
Major enterprises and service providers have embraced LoRaWAN as a core layer of
their infrastructure.
The question is no longer "Will this network even work?" but rather "How can we make it
more efficient and scalable?"
IoT has grown up. Deploying a sensor network today is less like a pilot project and more
like building a fiber network or a utility grid: a long-term asset designed to deliver
consistent value over many years.
Solar Energy Harvesting for Sustainable IoT Power
As the IoT market matured, so did energy-harvesting technology, offering a way to
address the battery problem head-on. Energy harvesting refers to capturing ambient
energy (like light, heat, motion, or radio waves) and converting it into electricity to power
devices[7]. For low-power IoT nodes, especially LoRaWAN sensors, this is no longer
theoretical. It's a proven way to enable maintenance-free operation. Among various
options, solar (photovoltaic) energy has emerged as the most practical and widely
adopted form of harvesting for IoT.[8]. It's simple, scalable, and effective across both
indoor and outdoor environments.
Outdoors, a small solar panel on a sensor node can continually recharge its power store
(whether a rechargeable battery or a supercapacitor), easily providing enough energy
each day to run the device. Impressively, even indoor lighting can generate usable
ambient light: modern indoor PV cells (like organic photovoltaic panels) produce on the
order of 50 μW per cm² under typical indoor light conditions (500–1000 lux), which is
sufficient to run ultra-low-power LoRaWAN sensor devices[9].
The design considerations are straightforward: size the solar cell appropriately, manage
energy storage for darker periods, and ensure adequate light exposure. Once those
factors are addressed, the payoff is enormous. Routine battery maintenance
disappears, enabling installations in hard-to-reach places: rooftops, warehouses, remote
fields, where traditional battery changes would have been impossible. [10]
