For most of my utility career, the dream of a fully connected national, coast-to-coast frequency-synchronized power grid has been discussed as though it might someday actually happen. We’ve connected the coasts with continuous rail lines, the Interstate Highway system and data/voice communication. And now we have the technology for a national grid — HVDC for the major, cross-country power arteries connected through FACTS (Flexible Alternating Current Transmission System) devices serving lateral AC lines. At last, we’ve solved the inherent engineering roadblocks to long-distance transmission.
An EE’s dream: some guy in Eastport, Maine, turns on the early-morning coffee pot and generators in California, snoozing during way-off-peak demand, jump to respond to the (albeit very micro) surge.
There are good arguments for a national grid: all generation could contribute to the national demand as peak load times travel from east to west, resulting in a flatter load curve, better asset efficiency, better acquisition and use of solar output, etc. And of course, a national grid would provide a handy backbone to access remote generation (wind, solar, nuclear), sort of plug and play on a grand scale.
We’ve even began moving towards connecting the nation’s three regional interconnections ala the Tres Amigas power hub being built in New Mexico. When completed (maybe in 2016), Tres Amigas will enable power transactions between the Western Interconnection, Eastern Interconnection and Texas Interconnection.
Still, a coast-to-coast power bus isn’t in our nation’s future. There are at least four reasons why:
1. A fully integrated national grid would maximize our exposure to cyber-attack, physical assault and natural disasters
In 2013, about a hundred .30 caliber rounds struck the PG&E Metcalf Transmission Substation near San Jose, California. Then in August 2014, intruders cut the fence and stole construction equipment, proving that even one of the nation’s largest utilities has a tough time protecting one of its largest substations near its largest load center.
Last November, National Security Agency (NSA) Director Michael Rogers testified that several countries have the ability to shut down the entire U.S. power grid and other critical infrastructure with a cyber-attack. "It is only a matter of the ‘when' not the ‘if’ that we are going to see something traumatic," he said.
Finally, the powers that be woke up, and last March, the Federal Energy Regulatory Commission (FERC) warned that a study showed that disabling nine key substations out of the nation's 55,000 substations would cause coast-to-coast blackouts, potentially lasting more than 18 months.
Thankfully, Metcalf wasn’t one of the critical nine. PG&E’s complex network was able to route around the disabled substation and except, perhaps, for the gunfire, customers were none the wiser.
But it’s not only the bad guys we have to worry about. Mother Nature gave us Superstorm Sandy and her relatives that have knocked out service to the Atlantic and Gulf coastal states. And, of course, there are the less newsworthy but horrific tornadoes, derechos and ice storms that shut off power in the Midwest.
Speaking of nature, we observe that in natural systems organized diversity is a better defense against predators and disease than uniformity. In fact, the mathematical measure of eco-stability is a function of diversity. Or, just looking at the screen in front of us, we know that software viruses cause maximum damage when the majority of users have a similar operating system, particularly when they’re networked with interdependent data and applications.
So, whether the threat is from bytes or bombs or floods, a network of generation and transmission with interdependent nodes is an attractive target. Micro-grids and self-generation? Well, not so much.
2. Big is No Longer Beautiful
For decades, utilities have had a love affair with big generation and big transmission. It’s been a good run. Build big and get a more or less guaranteed rate of return so you can build even bigger. That worked very well to support decades of rapid load growth, but those halcyon days are over. Money is tight, the Environmental Protection Agency is seemingly on the warpath against big generation, and the public is less and less tolerant of transmission rights-of-way and visual eyesores that only an engineer could love. And now, following state and federal government fumbles with deregulation, many utilities find that their biggest business assets are the distribution and customer systems.
Maybe the biggest driver is that the economies of scale have been replaced by economies of mass production. Beginning with the flood of aero-derivative gas turbines, siting smaller power plants closer to the load became increasingly desirable.
And what better topology than a micro-grid and/or on-site generation to offer custom power, that fabled business model that has never seemed to happen under the legacy one-size-fits-all delivery system. A utility could even own the on-site generation – see Distributed vs. Centralized Generation: Battle of the CEOs
Clearly, our industry attention is moving towards smaller more discrete assets.
3. Politics Won’t Allow It
The Interstate Highway System is often used as an example of how we could go about building a national grid. But the IHS was initially primarily a defense project. Following two wars, Dwight Eisenhower knew we needed a better way to ship troops and supplies around the nation in case of a coastal attack.
In contrast, our existing web of transmission lines was built in response to regional, not national, needs and planning. Interconnected regional lines are regulated by states, although interstate transmission is also governed by FERC.
Beginning with Thomas Edison’s various utility enterprises, the business of generating and delivering electric power has at least tried to be somewhat entrepreneurial. But the industry has frequently been mired in the ruts of regulative confusion. Starting with the Public Utility Holding Company Act of 1935 (PUHCA) and running through deregulation attempts in the last couple of decades, there has been a lack of uniform legislation agreement between regulators, government and utilities.
So, as that dog fight continues, do you think states and regional regulatory agencies would give up their power to the federal government to create a federally owned transmission system? Don’t think so.
4. We May Not Even Need a “Grid”
...at least for many of our customers. As John Baker points out in A Solar Battery Knockout? :
“Have we reached the cusp where distributed solar photovoltaic (PV) and battery storage are about to become a ‘utility in a box’, allowing customers the option to completely defect from the grid? Has solar-plus-storage become the long-feared one-two knockout blow for electric utilities? Some observers feel that the time is upon us.”
But we’re not just talking about the residential sector. Industrial rooftops offer an excellent opportunity for solar panels. And cheaper storage and better ways to absorb the inherent intermittency of renewable sources, integrated with natural gas generation, will make community micro-grids even more of a reality. We’re moving towards local generation and less dependence on a transmission grid to supply power.
Won’t we always need some sort of grid back-up? Yes, distribution networks certainly, at least for the foreseeable future. And some regional transmission to handle big conventional generation and remote renewables such as geothermal, wind and solar. And we’ll always need power pipelines to big industrial customers.
But a national, coast-to-coast, trans-regional power pipeline?