One thing on which most energy planners agree is that electricity will be the star performer in the world's decarbonized economy. But it will flop if nations only patch up and replicate the electric systems industrial economies built over the last century.

BloombergNEF (BNEF) estimates that a minimum of $21.4 trillion must be invested in the electricity grid by 2050 to support the world's net-zero trajectory. In the United States, 70 percent of the power lines and big transformers in the electric system are over 25 years old. The U.S. doesn't have enough transmission lines to move power from parts of the county with the best renewable energy resources.

Electricity provides only about a quarter of the energy Europe consumes. The EU Commission wants to raise that to 75 percent to decarbonize its economy by mid-century. But the grid in industrial countries needs more than modernization and expansion. We must reinvent how we generate, distribute, and store electricity. The current systems can't cope with today's dramatically different challenges.

For example, in the old electric system, we take fuels to stationary power plants. In the new system, we take "power plants" like wind turbines and solar farms to their "fuels," where the wind blows, and the sun shines.

Long-time threats

New electric systems must use sustainable fuels and contend with terrorism, cyber-attacks, and violent weather caused by climate change. "Electricity grids are the backbone of the energy transition, yet the networks we have today are not ready for the future," BNEF points out.

The power system is dangerously fragile even in the world’s largest economy. The U.S. electric grid has been called the world's biggest machine. It has more than 7,300 power plants that distribute electricity to nearly 160 million customers through 160,000 miles of high-voltage and millions of miles of low-voltage lines. Along the way, 55,000 substations adjust the system's voltage and perform several other tasks.

In a special report last year, Reuters concluded the U.S. power system is "creaky." For example, the number of power outages over the last six years doubled compared to the previous six years; the seven regional grid operators underestimate the threat of severe weather because they rely on historical data rather than anticipated threats from climate change; and the federal government lacks the authority to ensure that grid expansion and modernization will withstand wilder weather and accommodate electric vehicles and renewable power.

With so many parts and interconnections, the grid has always been vulnerable to disruption by even the simplest incidents. Many Americans remember when power lines sagged in the heat in 2003 and touched overgrown trees in Ohio. Some 50 million people lost power for two days, costing 11 lives and $6 billion. Climate change's growing impact on the grid is evident after every major tornado and hurricane when trees are uprooted and fall onto power lines. But the deadliest example of a grid catastrophe occurred in California in 2017 and 2018. Downed power lines, one nearly 100 years old, and faulty equipment sparked wildfires that killed 104 people and destroyed entire communities.

Cyber-attack is a growing threat, too. The U.S. news organization Politico reports that hackers tied to Russian used malicious software to nearly bring down a significant portion of America's power grid during the first weeks of the Ukraine invasion. A U.S. government website understates the risks when it calmly points out that the loss of electricity would "disrupt communications, water and transportation; close retail businesses, grocery stores, gas stations, ATMs, banks and other services; cause food spoilage and water contamination; and prevent use of medical devices."

U.S. defense and intelligence officials anticipated these threats years ago. In 1982, they commissioned a study of America's grid security. The result was a book titled "Brittle Power" by energy mavens Amory and Hunter Lovins. They cautioned:

The United States has for decades been undermining the foundations of its own strength. It has gradually built up an energy system prone to sudden, massive failures with catastrophic consequences. The energy that runs America is brittle—easily shattered by accident or malice. That fragility frustrates the efforts of our Armed Forces to defend a nation that literally can be turned off by a handful of people. It poses, indeed, a grave and growing threat to national security, life, and liberty. This danger comes not from hostile ideology but from misapplied technology. It is not a threat imposed on us by enemies abroad. It is a threat we have heedlessly—and needlessly—imposed on ourselves.

The National Academies, a nonprofit organization that serves as America's "pre-eminent source of high-quality, objective advice on science, engineering, and health," listed its concerns in a 2012 report:

Electric systems are not designed to withstand or quickly recover from damage inflicted simultaneously on multiple components. Such an attack could be carried out by knowledgeable attackers with little risk of detection or interdiction. Further well-planned and coordinated attacks by terrorists could leave the electric power system in a large region of the country at least partially disabled for a very long time.

Low-tech terrorism

Despite these cautions, we remain remarkably vulnerable. Over several months, militants attacked at least nine substations on the East and West coasts, cutting power for thousands of people. All it took were long rifles and a few bullets to shoot and disable transformers, a critical part of the electric system. The U.S. Federal Energy Regulatory Commission warned that similar attacks on just nine more carefully selected substations could take down the nation's entire power system.

Physical attacks on the U.S. power system rose more than 70 percent last year compared to 2021. Federal officials report nearly 4,500 attacks on the grid between 2020 and 2022. Some were domestic terrorism, and others were criminal acts, as vandals tried to steal valuable substation components like copper.

One grid-security activist in the United States points out, "The U.S. government has been concerned about the cybersecurity of the critical electric infrastructure since at least 2003; the security of the electric grid from physical threats since at least 1981; geomagnetic disturbance (GMD) threats since at least 1989; and electromagnetic pulse (EMP) threats since at least 1972. Now it's cybersecurity, climate change, and domestic terrorism."

Securing the grid

The United States is about to embark on a $65 billion modernization of America's aging grid to make it "reliable, resilient, flexible, and secure." Some experts say the investment should be closer to $2 trillion. Other nations also will have to make significant power system investments.

With electricity expected to play so large a part in a net-zero carbon economy, the question is whether nations will do enough to protect their power systems against these threats and others that emerge in the future.

In many nations, sprawling power systems will be impossible to police, so security must be built into the infrastructure. Power lines can be buried to protect them from weather – an expensive process but perhaps less costly than blackouts. Today's substations are located in the open, where they are easy targets for vandals and militants. Utilities should fortify them and stock extra transformers – the favorite target of rifle-toting saboteurs.

We need a more diverse, less centralized, and redundant power system with substantial battery storage, microgrids, and distributed generation by wind turbines, solar arrays, heat pumps, hydroelectric systems, etc. We should follow the example the U.S. military is setting by "islanding" its bases to produce their own clean power if the grid goes down. Critical civilian facilities like hospitals, wastewater and freshwater systems, communications, and first-responder facilities, should follow that example.

At the same time, governments should stay ahead of and defend against foreign cyber attackers by paying for the education of the most promising cyber-geeks. In exchange for tuition, they could continuously improve our defenses and our ability to enforce Mutual Assured Disruption against any nation that cyberattacks us. We can't expect a secure world where a wayward tree branch or high-school hacker can shut down the primary source of nations' energy. An electric economy might be the cleanest option for the future, but it is also the least secure. However, if there's one good thing about obsolete power systems, it's the opportunity to do them over and do them right.