The Future of Electricity Infrastructure

By Lorenzo Amicucci, Business Development Manager, Nordic Semiconductor

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Wireless technologies can pave the way to a clean energy future by helping electricity grids become more reliable even as they integrate more renewable energy

Number 7 on the list of the UN’s sustainable development goals is to “ensure access to affordable, reliable, sustainable and modern energy for all”. Progress towards this goal has been heartening with, for example, the proportion of the global population having access to electricity rising from 83 per cent in 2010 to 89 per cent in 2017.

Better yet, giant strides are also being made in how that electricity is generated. Today, almost a third of global electricity comes from renewable sources ((hydro, solar and wind). That number is sure to rise after leaders of the largest industrialized democracies at the G7 summit in June pledged to end support for coal power by the end of 2021. The U.S. has also pledged to achieve 100 per cent carbon pollution-free electricity by 2035, and the U.K. seeks to hit net zero emissions by 2050.

But these changes won’t be easy to accommodate using today’s electrical grids with their aged wires, poles, transformers and circuit breakers. Far from supporting increasing renewable energy, antiquated equipment is responsible for an increasing number of so-called interruption events that see consumers plunged into darkness, sometimes for hours.

RAM-1 uses Nordic’s nRF9160 SiP with its built-in GPS capabilities to precisely determine and relay electricity grid fault locations

Decades-old electricity grids weren’t built with renewables in mind. Rather, they were designed for the one-way flow of energy from relatively-few baseload power stations (fuelled by coal, oil, gas and uranium). New grids need to accommodate numerous distributed energy generation sources and two-way flows, even down to users feeding excess electricity back into the grid from rooftop solar panels.

Distributed generation also makes it much harder to achieve the balance between power generation and demand – which is critical to grid stability. For one, renewable energy is highly variable – clouds often cloak the sun and winds die down. Second, new technologies such as solar panels and batteries that sit “behind the meter” create blind spots for the grid operators responsible for maintaining that vital balance. Precise control of generation is vital because variations affect the turbine’s AC output frequency and large fluctuations in this frequency can damage equipment connected to the network.

A smarter, cleaner way forward

Enter “smart grids”; these upgraded and computerised networks are designed to improve grid reliability and eliminate the blind spots by gathering data about the behaviour of grid devices and users – be they generators, utilities or consumers. These smart grids are built on IoT technologies such as sensors, connected meters and other equipment, and make use of fast developing communications and data analytics technologies to harvest data and deliver new insights and capabilities. For example, sensors deployed across a smart grid will make it easier to track AC frequency fluctuations and react accordingly.

Smarter condition monitoring will also be a notable and early benefit. Today, fault detection typically requires a truck roll to dispatch a technician and pinpoint a failure after it has happended. This costs time, which translates to longer outages. In response, Slovenian firm Izoelektro has developed a device for remote monitoring of power grids and surge arresters that can be mounted on utility poles. The “RAM-1” device has integrated voltage, temperature, accelerometer and surge counter sensors that allow the monitoring of variables that might suggest an impending fault—for example, detection of excessive temperatures that might indicate a potential fire—allowing utilities to react ahead of an outage.

If failure does occur, because RAM-1 uses Nordic Semiconductor’s nRF9160 SiP with its built-in GPS capabilities, the unit can precisely determine and relay the fault location. The SiP also incorporates a powerful Arm Cortex M33 processor which allows a high degree of edge processing. Much of the data monitored by smart grid sensors is unchanging, simply confirming a variable is within acceptable limits. Transmitting that data is costly and burns battery power for little gain. Edge processing enables sifting of the data for trends and then transmits only the most critical insights—such as parameters nudging abnormal limits—maximizing battery life.

The nRF9160 supports LPWAN cellular technologies LTE-M and NB-IoT, which are ideal for smart grids as they offer tens of kilometres of range, use existing cellular network infrastructure and consume little power. The RAM-1 can last up to two decades in the field from just the power of a primary Li-MnO2 cell.

With the ability to proactively detect and isolate faults, in the event of an outage grid operators can redirect power along alternative routes using control systems and switching infrastructure such as automatic circuit reclosers. This “self-healing” capability has lessened the time customers experience an outage by up to 51 percent and reduced the number of customers affected by up to 45 percent, according to a U.S. Department of Energy report. In addition to electricity cables, gas and water pipelines could similarly benefit from these remote monitoring advancements.

Balancing act

As for maintaining grid balance as the uptake of variable energy sources like renewables increase, the key is better visibility. “If you have really up-to-date information on all the flows on your grid, you can tolerate a little more variability,” says energy consultant and author Peter Fox-Penner. “The smart grid will monitor everything at a very, very fine level of detail and reacts really fast, so operators will have time to fire up another [generating] plant if wind speed drops or a big cloud formation reduces solar output.”

Millions of Advanced Metering Infrastructure devices—or “smart meters”—are now being deployed to provide the insights into power usage energy flows across the grid to which Fox-Penner refers. Keeping pace with and connecting all these devices is difficult to do with wired connections that demand additional network and physical infrastructure. Operators are instead turning to secure long-range wireless connectivity options such as NB-IoT and LTE-M.

The shift to the smart grid is also an opportunity to replace aging and proprietary monitoring systems that are highly vulnerable to cyber-attack with more modern IoT gateways designed from the ground up with security in mind. For example, Nordic’s nRF9160 cellular IoT solution offers layers of security through the use of Arm TrustZone’s hardware-enforced isolation of critical components.

The benefits heralded by this “Internet of Energy” are many. For end users, a more reliable supply of energy will be coupled with lower energy costs. For utilities and energy operators, the promise of reduced maintenance costs through proactive fault detection is significant, as is an enhanced ability to manage the reliability of supply and deepen customer relationships by leveraging energy use data. Governments and policymakers will also use this data to inform smarter planning of future grid infrastructure. But the enduring winners, as smart grids drive meaningful emissions reductions, will be the future generations inhabiting planet Earth.