With more than 1.8 billion smart meter connections forecast to be in use by 2027 according to a study by Juniper Research, cellular and low power IoT connectivity is being deployed to connect meters and enable secure, robust data transmission. There is a range of choices for organizations deploying smart meters and much depends on the characteristics of the deployment and the project’s aims, not only at launch but also during each meter’s lifespan which can extend to two decades in some cases.

There’s no typical smart meter so your decision starts with identifying the type of meter you need a module for, the applications and use cases the module will support and the projected lifespan of the smart meter. There are significant differences to consider between water meters, which have very long lifespans of two decades or more and rely on batteries for power, and electricity meters, which have lifespans of about a decade and can be powered from the electricity supply they monitor.

Selecting a module for a water meter is relatively straightforward because the meter will send relatively modest amounts of data and much of its activity will focus on routine counting of water consumption. Therefore, a basic level of low power connectivity, which extends battery life, is all that’s needed here.

Electricity meters in contrast have a wider range of variables. You need to consider not only how long the meter will be deployed for but also which use cases it will support. Smart electricity meters typically go far beyond simply counting consumption with emerging use cases taking into account power generation from renewable sources on domestic and commercial premises plus the need to prepare the grid for demand spikes such as those necessitated by electric vehicle charging.

Innovative utilities providers are also assessing the extent to which meter connectivity and edge intelligence can be applied to wider smart home use cases. If this is an intention or even an aspiration, meter projects need to allow for connectivity and module performance that can support multiple users and use cases with the ability to control loads after the meter, such as for heat pumps or battery charging, to balance the energy consumption in the grid.

Gas meters face fewer challenges because they are usually replaced every ten years so and battery life can accommodate their communication needs, which are more closely related to water metering than energy meters.

Connectivity needs for smart metering

A common factor for all types of smart meters is that they are typically located in hard to reach places such as basements so ability to connect to networks needs to be considered with care. The needs of meters appear to be most closely aligned with low power wireless connectivity such as LoRa or NB-IoT. However, these technologies have incomplete coverage so LTE networks, which are replacing 2G and 3G, are often utilized thanks to their ubiquitous coverage.

To overcome problems with communications in harsh environments or difficult to reach locations, the metering industry is using the 450 MHz band with multiple radio access technologies: NB-IoT, Cat M and LTE with future introduction of 5G as well. Lower frequencies offer better propagation with lower power consumption.

2G and 3G cellular networks are being retired across the globe, although in some markets the lifespan of 2G is being extended purely to support smart meter contractual obligations. That leaves 4G LTE as the most popular cellular option for smart metering. Low power variants such as LTE-M provide the power efficiency, data throughput and cost blend that matches the needs of smart metering.

With the introduction of extended discontinuous reception (eDRX) and power saving mode (PSM) which help reduce module power consumption, LTE Cat 1 and Cat 1 bis modules are also becoming of interest for metering applications. These technologies are mainly being adopted for electricity meters because they can serve use cases where more bandwidth is needed.

Continued deployment of NB-IoT capacity will see it gain further traction, but few expect 5G to be utilized because smart meters simply don’t need the capacity 5G offers and so its cost is hard to justify.

Choosing the ideal module for smart metering applications

Quectel sees the bulk of the cellular smart metering market selecting either NB-IoT modules such as its B660K-GL high-performance LTE Cat NB2 module which has been designed to meet the needs of the smart metering industry, or its BG95 multi-mode LPWA module range. The B660K-GL offers low power consumption which is vital for deployments with expected lifecycles of 15 or 20 years.

The Quectel BG95 module family offers LTE Cat M1, Cat NB2 and EGRPS variants with integrated GNSS. The module provides extensive flexibility in terms of network technology and for future upgrades while delivering maximum data rates of 588 kbps downlink and 1119 kbps uplink using LTE Cat M1.

In addition, Quectel’s EG912N-EN LTE 450 Cat 1 module supports 450MHz and offers a maximum 10Mbps downlink rate and 5Mbps uplink rate. The EG915U-EU module is also well-suited for electricity meter deployments, offering Cat 1 bis performance.

Our advice would be to identify your project’s priorities and then zero in on a module that balances cost, data throughput and power consumption with the available wireless networks in your deployment’s locations. Plans to go beyond basic metering of consumption during the lifespan of the current generation of smart meters should also be accommodated. This is a choice for the long-term and mistakes made now will be impossible to rectify easily in a few years’ time.