As the smart meter market matures, old and new ideas are converging to give utilities the ability to deploy affordable and capable networks. Now, utilities can mix and match the best features of both cellular and mesh technology.
In this post, we’ll cover how the hybrid grid has evolved and how it benefits utilities and their customers.
Customer Data-Gathering: from Manual to Mesh
Utilities have been using the telecommunications grid to gather data from customers for years, but this solution has always been used sparingly. Deployment of home-grown solutions using land lines – and more recently, cellular hook-ups – were restricted to remote customers where manual meter reading was economically prohibitive.
In urban settings, however, density allowed meter vendors to develop proprietary mesh networks (meter to meter) as a more affordable solution to manual meter readers. Mesh networks use individual meters with radios to relay data (like stepping stones on a pond) to a backhaul router. A wide variety of technologies – including WiMAX, Ethernet, satellite and cellular – is then used for backhaul systems to communicate with backend systems.
Since mesh networks rely on meters and network devices with radios to communicate with one another, they have a natural redundancy in dense areas. If one meter “goes dark” and stops communicating, then those meters relying on it find a new path to the backhaul endpoint. Dense suburban areas with lots of outdoor meters on the sides of single or multi-dwelling buildings were ideal settings for the development of mesh networks.
The problem for mesh networks begin when meters are:
- Inside large commercial or multiple dwelling unit (MDU)/apartment buildings, where thick concrete walls or energy-efficient glass can interfere with signal.
- In a location where low density cannot justify the placement of a device to connect with the backhaul (router).
How Cellular Technology can Tackle the Pain Points of Mesh
As meter vendors were developing their proprietary mesh technologies, cellular carriers were expanding their networks across North America. Now that the deployment of cellular networks has become so common, even in very rural areas, cellular technology has risen in popularity with meter vendors to overcome some of the challenges of metering isolated customers.
For example, many small communities strung out along highways are covered by a major cellular provider, making them ideal for use of direct cellular meters instead of a mesh network. Often, houses are arranged in single file along a highway and provide a “string of pearls”, requiring repeaters between residences. Currently, if one device in the string becomes non-communicative, all devices behind the non-communicating device will also fail to communicate, breaking the string. Instead of deploying a mesh network in this community, utility providers now have the option to install direct cellular meters.
Similarly, a small cluster of commercial buildings located on the fringe of a community may not justify installation of a mesh router, but are ideally suited for deployment of direct cellular meters.
Takeaway: Hybrid Networks Get the Best of Both Mesh and Cellular
Using the strengths of both direct cellular and mesh networks makes sense for utilities that cover diverse geographic and/or urban and rural regions. Many Smart Grid vendors are working directly with telecommunications companies on large cellular plans in order to decrease the cost of cellular-only deployments, but until those costs can be brought down, cell-only solutions will remain impractical and costly. Hybrid networks, on the other hand, leverage the benefits of a utility-deployed mesh network and the advantage of direct cellular meters where mesh isn’t feasible.
Just as cellular networks have spread over the last 20 years, ubiquitous Wi-Fi in urban areas is the likely next step. It’s only a matter of time before utilities will have access to a broad selection of tools for data gathering, with each option selected for its ability to provide cost-effective, seamless service.
ABOUT THE AUTHOR
Jackie has held several AMI project positions over the years. When she isn’t working on an IPv6 migration schedule and reporting, impacts of firmware upgrades, or meter configuration changes, she enjoys life with her family on the Eastside of Vancouver, British Columbia.
JTS prides itself on making the complex simple. As a niche firm focused exclusively on the utility industry, our team has the practical operational knowledge, innovative thinking and sound business sense to help utilities safely, reliably and efficiently modernize their grid and transform their business for future generations.