How the internet of things is monitoring the Earth’s resources


22 Apr 2022

Image: Alistair Fulton

Alistair Fulton from LoRa developer Semtech runs through some climate-friendly applications using LoRaWAN-enabled devices.

The development of technology to monitor the way in which we use increasingly scarce resources is vital for minimising the environmental impact of human activity. Earth Day (22 April) is dedicated to highlighting the need to make the most of the resources that we have and the role technology can play in this.

The latest technology developments in low power wide area networks (LPWAN) are opening up the ability to monitor all kinds of equipment in remote areas. This technology now provides low-power links direct to satellite that can be combined with existing networks and cloud services. This is a powerful combination for both monitoring infrastructure and also for providing data that enables that infrastructure to be more efficient by reducing waste and making the best use of resources.

LPWAN offers the most power-efficient technology for environmental monitoring and is already widely used in the unlicensed 868MHz frequency band in Europe or 912MHz in North America.

The physics of these sub-GHz bands give significantly longer range than the bands at 2.4GHz used for Wi-Fi and Bluetooth, but with the trade-off of lower data rates.

For monitoring, however, this lower data rate is less of an issue compared to the benefits of the longer battery life that comes from the lower power consumption or, in some cases, the ability to remove the battery entirely.

Water monitoring solutions for irrigation schemes are now using solar panels to provide power for the sensor nodes across hundreds of square kilometres of desert. This removes the need for someone to go out and manually change the batteries.

Moreover, using the data sent to cloud and artificial intelligence (AI) systems for automated management and optimisation helps to boost crop yields without having to increase the use of fertilisers.

Other LPWAN sensors are using AI in forests to look out for wildfires. The incidence of wildfires is growing, destroying thousands of hectares of forest every year. Sensors on trees can detect levels of carbon dioxide and oxygen in the air and monitor the temperature, giving early warning of the conditions where wildfires are prone to occur. This gives first responders more time to organise prevention, or an effective defence.

However, these sensors still need to connect to a gateway, which for sub-GHz networks provides the link to a cable or cellular network. The latest enhancements to LPWAN protocols now allow sensors on the ground to connect directly to satellites in low Earth orbit.

The LoRa Alliance now has five satellite operators and network partners working to connect LPWAN sensors without the need for gateways on the ground.

The new capabilities that make a signal more robust to reach a satellite can also enhance the efficiency of smart cities. The new protocol gives smart meters greater reach and enables cheaper, lower-power monitors to refine the use of electricity and water, reducing leaks, and minimising waste. Sensors can be placed in many more locations without the worry or expense of having to replace the batteries.

Household leaks waste nearly 900bn gallons of water a year according to the Environmental Protection Agency in the US, and integrating LPWAN into water management systems and smart meters can identify areas where problems need to be fixed, helping to reduce water waste.

Other enhancements are also boosting the use of LPWAN networks in smart city and supply chain applications.

The 2.4GHz band is popular across smart cities as it is an unlicensed band available anywhere in the world. However, that band is full of different networks, which can create interference. Wi-Fi, Bluetooth, Matter, Zigbee, Thread and proprietary systems are all present for different applications.

Having an LPWAN system that is more robust in the 2.4GHz band means that sensors using that band can be used anywhere in the world, linking to any number of gateways. This also helps significantly reduce power consumption. Many protocols use a collision detection and retry architecture, and crowded bands mean more retransmission and higher power use. Using the more rugged LoRaWAN standard helps to keep power use low and extend battery life.

This can be particularly helpful across the supply chain. A low-cost way of knowing where containers are throughout the process of shipping, or where vehicles or equipment are located, is just the first step. This data can be ingested into databases and machine learning can then identify more ways to optimise the supply chain to make it more efficient. This increased efficiency across the globe can make a massive difference to help reduce the use of resources.

For example, Ercogener in France has developed an end-to-end asset tracking solution utilising Semtech’s LoRa devices and the LoRaWAN LPWAN standard that is used by the national state-owned railway company to track shipments across its rail network.

Elsewhere in France, JRI uses LPWAN sensors linked to the cloud to monitor the temperature of refrigerated containers for supermarkets, whether in situ or in transit. This both improves the efficiency of the transportation system but also ensures that the temperature of shipments are tracked and monitored. This can highlight problems before they become critical and prevent perishable shipments going to waste.

Optimising resources is vital for the future of our planet. The combination of global LPWAN devices and cloud services, including AI and machine learning on the data, are actively improving the way we use and conserve increasingly scarce resources.

By Alistair Fulton

Alistair Fulton is senior vice-president and general manager of the wireless and sensing products group at Semtech is the developer of LoRa, a long-range networking used by millions of internet of things devices worldwide.

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