Steven Tompkins, director of sector development for agriculture and rail with Inmarsat, discusses the role of satellite communications in ensuring that shipments of the COVID-19 vaccine remain at designated temperatures for safe transport and delivery.

Satellites have served a key role in supply-chain tracking, tracing and monitoring, including for temperature-sensitive vaccines, for many years. As the only technology that can be deployed on land, sea and air, it’s the “perfect sweet spot for the multimodal supply chain,” Tompkins says. Certain of the COVID-19 vaccines are especially sensitive, with the need to be maintained in ultra-cold storage at temperatures of around minus 70 degrees C.

Sensors inserted into containers of the vaccine relay data on temperature and humidity to a satellite terminal which beams it up to the satellite, then down to a ground station, from which it’s then sent to a user’s smartphone or other monitoring device. The whole process takes no more than a second and a half.

Inmarsat’s satellites are in geosynchronous orbit — meaning they are continually hovering above a designated portion of the earth — at an altitude of around 35,000 kilometers. Because they fly higher than low-orbit craft, they aren’t subject to disruption of signals due to weather events, Tompkins said. Others using that particular communications band include the government, military, maritime and aviation sectors, all of which need an absolutely reliable flow of data. Low-orbit satellites are better suited for the transfer of higher volumes of data, Tompkins says.

In terms of cost per megabyte, satellite communications are more expensive than cellular systems, but because supply-chain data moves in relatively small volumes, the actual cost is similar to cellular plans, according to Tompkins. As a result, the technology is widely used by transportation and logistics providers.