What The 21st Century Grid Needs – 5 Actions the Power Industry Should Consider

October 2, 2022

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Grid resilience — Image credit: Perillon

Hurricane Ian in the last week knocked out the Cuban power grid, carved a destructive swath through Florida and assaulted the Carolinas. Headlines include stories about lives and property losses from storm surges, flooding, destroyed homes, eroded coastlines, uprooted trees, and loss of power.

The previous week was Hurricane Fiona’s turn to do a number on Puerto Rico and then Atlantic Canada producing similar headlines. Hundreds of thousands of customers in both locales, dependent on grid-delivered electricity, found themselves without. Many two weeks later continue to live without power.

Whether you believe these weather events are caused by anthropogenic climate change or just extreme one-offs, it is clear that modern power grids are not holding up to face nature’s worst. What’s needed is a 21st-century grid that is smart, flexible, and adaptable. But that is not what we have right now for the most part.

Here are five actions for grid designers and operators to embrace.

1. Fully Integrate Renewable Sources Into Grid Infrastructure

Solar and wind power are replacing coal-fired power stations. Even natural gas-burning power plants are increasingly being relegated to operate at peak periods to supplement renewable sources to feed the grid. But wind and solar are variable sources of electricity posing a challenge when being integrated into the grid.

Utilities are further challenged by customers producing their own renewable electricity from rooftop solar changing how energy flows back and forth within the 24-hour cycle. Grid design needs to safely and efficiently control these bi-directional power flows. And the grid needs to include new resources to seamlessly feed supplemental non-renewable or battery-stored energy as needed. It’s a tall hill to climb.

Balancing supply and demand means knowing what the net load requirements are at all times. How much renewable energy is going into the grid, how much is expected, and how to respond instantaneously to the variability? All this is possible through a smart grid infrastructure that delivers second-by-second data to energy providers.

The call for grid flexibility means an infrastructure that integrates large-scale energy storage, draws from areas where renewable resources are plentiful and combines multiple renewable sources beyond wind and solar including hydroelectric, geothermal, tide and wave. It means operators of the grid anticipating and pre-feeding energy to lessen demand peaks and valleys.

2. Add Distributed Energy And Microgrids to Grid Infrastructure

Harvard University created Harvard Energy & Utilities when it decided to adopt microgrids and distributed energy. The university owns its own heating and power plant that uses natural gas and operates a 7.5 Megawatt microgrid on the Cambridge, Massachusetts campus. The university earns alternative energy credits from the state because it has little requirement for being always connected to the larger power grid.

Harvard’s distributed energy system and microgrid represent a growing trend. Most distributed energy systems are often small community and neighbourhood projects. They can be a cluster of buildings. Energy can come from rooftop solar with backup battery storage systems. They can include emergency diesel generators. And often they are only indirectly or intermittently connected to the high-voltage energy grid.

Microgrids can disconnect from the main energy grid and operate autonomously. Their presence mitigates grid disturbances allowing for faster system response and recovery. In the face of hurricanes like Fiona and Ian, distributed energy and microgrids add resilience allowing islands of energy stability to function even in the presence of large grid failure.

3. Harden The Grid For Climate And Extreme Weather Resilience

In recent years power grid failures have made headline news. The power grid of today doesn’t accommodate extreme wind, rain, ice, snow, drought, and other weather phenomena. The power grid doesn’t accommodate dropping water levels at hydroelectric facilities or the reverse along coastlines where sea levels are rising. The impacts of anthropogenic climate change this century and beyond will make things harder for grid operators.

What steps are needed to make the grid climate resilient? A recent McKinsey report identifies a number of actions grid operators can take including:

asset mapping including developing severe event scenarios to determine where risks are greatest
grid vulnerability and impact cases to identify failure probabilities in light of different extreme events.
grid-impact modelling of power and load flows and the impact of regional failures on overall grid functionality to identify where hardening is most needed.
planned interventions and preventive maintenance solutions to head off grid failures.
mitigation and adaptation becoming integral to new grid design and operations.

4. Make The Last Mile More Resilient Than It Is Today

I currently live on a street with few overhead wires. That’s because the powerlines, cable, and telephony infrastructure is all belowground. When Toronto had an ice storm in 2013 causing much of the city’s grid infrastructure to fail, this area never lost its lights or heat. Unfortunately for us, we hadn’t yet moved here and were among the tens of thousands who had to cope with the cold and dark just before Christmas.

Where we lived, no more than a kilometre away from where we are today, tens of thousands of the city’s trees either toppled or lost limbs to the ice and in the process destroyed the above-ground network of power, cable, and telephone lines. The morning after the ice storm hit as I walked my dog through streets filled with the debris of falling limbs live wires were lying across roads helter-skelter. It was chaotic and dangerous and it lasted over a week.

One of the reasons for Toronto’s catastrophic grid failure was caused by the neglect of the city’s urban tree canopy. Budget cutbacks reduced tree maintenance with limbs growing to impede powerlines. Homeowners were just as unaware or unmotivated to deal with the trees on private property.

When Pacific Gas & Electric’s transmission corridors through tinder-dry forest sparked the Campfire that burned Paradise, California to the ground, the utility pled guilty to 84 manslaughter counts in court. Today, the company provides guidance to homeowners in dealing with trees and powerlines.

One of the easiest ways to create last-mile resilience is to bury the lines. With no big above-ground transmission towers and no poles with strung-out hanging wires, Toronto’s ice storm and California’s wildfires would have exacted a much smaller toll.

And as mentioned before, developing microgrids and distributed energy networks means local grid autonomy.

5. Use Powerlines To Transmit Both Data And Energy

A 21st-century smart grid should not only deliver electricity but also combine sensing, communication and control. Power line communication (PLC) is an idea that I first became aware of in my data network consulting days back in the 1990s. I came across a DARPA-funded project that was using grid powerlines to do point-to-point data transmission. The challenges were many. High-voltage transmission lines are not intended for sending bytes over long distances. High-voltage alternating current (HVAC) and 0s and 1s don’t mix very well. The biggest pain was overcoming data losses during the last mile when stepped-down transformers reduced the voltage going into homes and businesses and played havoc with the bits and bytes.

But two decades have passed since witnessing those first experiments and it is time to revisit the technology. Renewable energy that produces high-voltage direct current (HVDC) is more efficient than HVAC and imposes fewer challenges to those who want to send bytes over powerlines.

Ersan Kabalci, Faculty of Engineering and Architecture, Nevşehir Hacı Bektaş Veli University, and Yasin Kabalci, Faculty of Engineering, Niğde Ömer Halisdemir University, in a 2019 book entitled, From Smart Grid to Internet of Energy, described the advantages of using powerlines for data communications over a smart grid.

Power grids are among the largest networks in the world. The universal existence of powerlines provides a transmission corridor for other things to travel with electricity. Imagine homes and businesses filled with smart appliances and computers that get all the juice and data needed simply by plugging one wire into an electric outlet. This would be a one-wire world rather than the tangled spaghetti we deal with today.