Smart grids have been with us for over a decade. But for many power industry stakeholders, they’re associated almost exclusively with smart meters. Remote meter reading is certainly a compelling use case, and one which justified many initial deployments, especially in the U.S. where end-customer sites are spread out over large distances. But there’s much more to smart grids today.
Mounting requirements for improved grid reliability, resilience, and distribution efficiency mean utilities can leverage many more benefits from their smart grid and meter deployments. But only if they have the right communications infrastructure in place.
The Right Topology
The field area network (FAN) is arguably one of the most critical elements of this infrastructure, enabling connectivity between customer meters and distribution networks on a very large scale—effectively putting the “smart” in smart grid. The right network topology is key. Wireless mesh offers several advantages over star networks.
First, because you’re not routing traffic through a centralized collection point, it opens the door to the benefits of deploying edge computing in distribution network locations. Thus, you can collect and process data directly from smart meters, faster and more efficiently.
Decentralized mesh networks also make fault detection and management easier. With ubiquitous connectivity you’re able to put sensors on the distribution network to spot problems early, and reroute power around areas experiencing outages. That not only improves the customer experience, it can save operational costs by enabling utilities to pinpoint exactly where they need to send out engineers to fix a problem.
Pole-tilt sensors are a great example, empowering providers to immediately spot when overhead lines are down and even predict when they may be about to fail. In a world where extreme weather is an increasingly regular occurrence, more and more utilities will need to avail themselves of predictive maintenance, and measures to enhance grid resilience and reliability.
The Cost Equation
For any business, effective cost management is also going to be crucial. Mesh networks can be self-healing, so data can be re-routed if there’s an outage. And transmissions are usually made over shorter distances, so utilities have the advantage of enhanced performance and power efficiency. By spotting outages early on, there’s also an opportunity to isolate and disconnect a misbehaving part of the network, potentially reducing the costs associated with a faulty device dumping power.
Mesh-based FANs could also support voltage/VAR optimization (VVO) efforts to reduce energy wastage. In many countries, utilities are mandated to provide a minimum voltage to reach their subscribers’ smart meters, which means they often provide unnecessarily high voltages through the distribution network to guarantee these levels. But by monitoring voltage at the meter, and including VVO sensors and equipment to the network, those same utilities can measure exactly how much voltage they’re providing and reduce it if necessary, hence reducing power wasted in the network. Recent stats are hard to find, but one U.S. government estimate claims utilities that have implemented VVO have reported 1% to 4% savings on initial deployments.
There’s also a cost to the planet of energy production, which is why many providers are looking at ways to add more power from renewables to their networks. But while traditional sources like coal-fired and nuclear power stations offer fairly good stability, solar, wind, and other renewables can lead to huge variations in power generation. To manage this effectively, providers need better control of their grids. Once again, mesh networks supply distributed data communications at lower latency, meaning utilities can use more edge computing on their distribution networks for greater control.
Why Open Standards Matter
Topologies aside, edge computing demands strong cybersecurity baked into equipment from the start. To support this security-by-design approach, companies need to choose a communications ecosystem that is standards-based—ensuring all components are stress-tested and follow the latest international security documentation and guidance. That means support for strong encryption and certificate-based security for all edge devices, for example.
It’s not just about security. Open standards create the environment for interoperable equipment and provide a greater choice of components for distribution network stakeholders. If a utility is already using a multitude of niche products across its network, the last thing the company will want to do is spend several years developing communications equipment for it. If standards-based modules can be bought and integrated seamlessly, it reduces time-to-market, drives innovation, and reduces costs. Plus, companies will be better insulated from stranded assets as technology evolves. That’s just good business sense, whatever kind of smart infrastructure is being built.
—Phil Beecher ([email protected]) is the president and CEO of Wi-SUN Alliance, a global non-profit member-based association driving the proliferation of interoperable wireless solutions for use in smart cities and other Internet of Things (IoT) applications.