Nordic Semiconductor’s nRF9151 module powers Wirepas DECT NR+ implementation to enable smart metering in Africa

Sustainable Energy Technologies’ NR+ solution delivers reliable, secure, long range and scalable smart metering thanks to Nordic’s nRF9151 module and Wirepas firmware

South African design and manufacturing company, Sustainable Energy Technologies (SET), has launched a DECT NR+ (NR+) -based Wirepas RF mesh network smart metering solution deployed on Nordic Semiconductor’s next generation nRF9151 module, the lowest power cellular IoT and NR+ solution with industry-leading battery lifetime performance.

The solution has been developed for electricity distribution utilities and meter manufacturers to enable Africa’s transition to smart energy solutions, with an initial focus on South Africa and Kenya. Cape Town-based technology consultancy, Pentafortis, is assisting SET with business and partnership development in the identified territories.

Currently two technologies dominate metering solutions in Africa, power line carrier (PLC) and cellular. For PLC solutions, pre-paid meters communicate over physical power lines, sending data back to a data concentrator unit, that in turn sends it to the Cloud. For cellular solutions, each pre-paid meter has a cellular modem that communicates to a cellular base station, with data then backhauled to an energy company’s software platform. While both technologies are proven, cellular meters require a SIM card that can be difficult for utilities to manage, and blackspots make coverage sometimes unreliable. PLC solutions on the other hand do not work well in the event of power outages—a regular occurrence in Africa—while renewable energy sources added to the grid can also negatively affect PLC communications.

Smart metering made easy

The Wirepas NR+ implementation on Nordic’s nRF9151 module addresses all of the limitations of PLC and cellular meters, while continuously collecting near real time energy data and enabling two-way network communication for remote meter monitoring. Each meter has a Network Interface Card (NIC) with SET’s nRF9151 module-based solution incorporated, enabling the smart meters to wirelessly relay data between each other until it reaches a gateway. From the gateway the data is backhauled via a cellular connection to the utility’s Cloud platform.

“Many areas, particularly in Africa, suffer from poor cellular network coverage,” says Joseph Wamicha, CEO, Sustainable Energy Technologies. “With NR+, smart meters extend and strengthen wireless network coverage. In urban environments each smart meter can connect with over 50 neighboring meters, and a singular cellular subscription can be shared across 1,000 smart meters.

“Also, traditional cellular smart meters typically send data overnight, or a few times per day, because of the cost of data. This lacks ‘real time’ visibility. With NR+, data can be transmitted every minute without a significant increase in cellular subscription fees.”

Nordic’s strong technical support and reference designs, fast response times from application engineers, and reliable supply chain ensuring component availability, reduced our costs and accelerated time to market.

Joseph Wamicha, CEO, Sustainable Energy Technologies

nRF9151 tailored for NR+ and cellular IoT

Nordic’s nRF9151 low power module is specifically designed for DECT NR+ and cellular IoT applications. Support for Wirepas’ NR+ stack enables massive mesh applications that prioritize reliability, security, long range, and scalability. The nRF9151’s high transmit power ensures long-range communication even in areas with weak signal conditions, while its superior receiver sensitivity allows the device to detect weak signals from distant smart meters or network nodes. The 1 MB non-volatile memory (NVM) and 256 KB RAM enables complex metering applications, while its compact footprint (12 by 11 mm) makes it ideal for integration into an NIC inside smart meters.

“At its core, smart metering depends on reliable communication and Nordic Semiconductor’s and Wirepas’ proven expertise and technology enables us to deliver robust, scalable, and self-healing network connectivity for smart meters,” continues Wamicha. “During development, the nRF Connect SDK significantly streamlined development with its pre-built libraries, security features, and optimized communication protocols.

“This combined with Nordic’s strong technical support and reference designs, fast response times from application engineers, and reliable supply chain ensuring component availability, reduced our costs and accelerated time to market.”