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The drumbeat began with the rattling of a snare drum or two; now the tympani are being bludgeoned with sledge hammers. As a Washington Post headline puts it today: “A summer of blackouts? Wheezing power grid leaves states at risk.” The article — one of many like it appearing in heavyweight publications in recent weeks — says that the nation’s power grid is “under stress like never before,” and “could buckle in large areas of the country” with the onset of a summer that is forecast to be brutally hot.
Bloomberg takes it even further, pointing out that the forecasts of extreme heat, and the fragility of the power grid needed for air conditioning, apply to most of the countries of the northern hemisphere. Around the world, it says, “A hot, deadly summer is coming with frequent blackouts.”
A couple of things we need to remember about any electrical grid:
- Electricity travels at the speed of light.
- Any demand for electricity that is not fully and instantly met by available generated capacity causes the voltage of the whole grid to drop, potentially doing serious damage to electric motors and electronics. That is called a brownout.
- If a brownout occurs, automatic circuit breakers take down the grid to prevent extensive damage. That is called a blackout, and getting the grid back up and running after one is a lengthy and complicated process.
- That is why grid managers must have on line at all times enough generated power to meet not just the current demand, but any additional demand that might occur. They spend a lot of time and effort predicting demand, and this year their own predictions are scaring the livers out of them. The Midwest regional grid, to cite just one example of many, expects demand to exceed supply this summer by the amount of energy needed to power 3.7 million homes.
- Grid managers have to have a stable, constant supply of power available to them. Solar and wind power drive them crazy because the sun and wind quit at dark. Gas and coal fueled generating stations cannot be shut down at dawn and fired up at dusk, it takes much of the day just to shut them down. So they run all day even though their output is not needed.
Few of these problems apply when electrical energy is produced where it’s consumed. Our family’s first electricity came from a “light plant,” which is what we called a generator, that had a sensor; when it got dark and you flipped a light switch, the sensor detected the demand, fired up the generator, and when it was up and running opened the circuit. No problem. If you have solar or hydro or wind energy, you have to scale back your demand to avoid overtaxing your system, but since you are both the producer and consumer that is easy to do. Impossible for a national grid.
It is also true that few of these problems would exist had the grid been maintained, repaired and upgraded during the last 50 years or so. Instead, it has been allowed to decay. Now, global warming is drying up the source of hydro power and superheating the air-conditioned homes and offices of the entire country. The time-honored blandishment of the experts and the politicians — “we better do something soon or it’s going to get bad” — has expired. “Soon” has become right now.
And now is when the government and the auto industry has decided we must all convert to electric cars and trucks, thus transferring to this aged, creaky, dying grid the full weight of one-third of all the energy consumed in this country — energy used for transportation, formerly provided by fossil fuels. What could possibly go wrong?
Put solar panels on our rooftop last summer and this summer we’re scheduled to buy an EV Ford lightning. So, we’re all good, right?
I would think so, if you have enough solar juice to charge the Lightning. Awesome truck.
yep, you made it! Hope your roof is the size of a football pitch!
Hi Tom,
What is generally not understood about large scale coal fired generators is that they were constructed so as to run continuously. A mate of mine who is an electrical engineer and works on sub stations said to me that those huge machines are only able to be shut down and fired up again a couple of dozen times over their economic lifespan.
A good example of what you are describing occurred on Norfolk Island. Too many houses installed rooftop solar power and one day supply exceeded demand, and the voltage ran too high and the system popped. In that case the main generator was a diesel generator.
I’ve lived with off grid solar power for about thirteen years now, and up time is about 99% at 37.5 degrees latitude south. That sounds good until you comprehend that 1% down time is the equivalent of 3 days per year that the sun utterly fails to provide enough and you have to run for the fossil fuel powered generator (and this household was set up to use very little electricity and we have a lot of solar panels installed). And for three weeks either side of the winter solstice (i.e. right now), the sun is low enough in the sky that each day is a bit touch and go. There is no way that an electric vehicle could be charged under such conditions. Some days the sun provides a mere 15 minutes of peak sunlight (i.e. a 200W panel will produce 50Wh for an entire day).
I would not bet the farm on this technology, and the house is not connected to the grid. And I hear credible stories that because of the massive roll out of rooftop grid connected solar down under, sometimes the voltage on the household side of the sub stations (i.e. transformers) is rising too high.
The whole thing is an abuse of the commons.
As to air conditioning, I have a theory that the houses being constructed now are not fit for the climate they’re constructed in. It was not always this way. And this house has no air conditioning and a few years back a summer day reached 111’F. That’s hot.
Cheers
Chris
Always good to hear from someone who actually walks the walk. Thanks for sharing your experience with us.
“…few of these problems would exist had the grid been maintained, repaired and upgraded during the last 50 years or so. Instead, it has been allowed to decay.” Another sad reminder that we knew EVERYTHING we needed to know 50 years ago, and instead opted for Happy Motoring and Morning in America.
I would like to second Chris on the inappropriate buildings that have been put up all over the world the last 50 years.
An anecdote from the outskirts of Shanghai, where I worked for three years a decade back:
One of my colleagues had grown up in Kunshan town, in a small farm house with bamboo roof and passive cooling design with shade trees and solar driven breeze. The neighbourhood was razed and her family got a modern apartment in a concrete building. Hot water in the tap. Modern luxuries like water toilet (but now flushing nutrients into the sea instead of back to the land). Big panorama windows to the south.
In the summer, with outdoor air temperatures around 40C (105F) the new concrete building was heating up in the sun, and the panorama window acted as a greenhouse to make half of the apartment utterly unlivable for several months each year, even if they spent a large part of household income on electricity for an AC cooler.
We build very inefficient infrastructure these days, just to look “modern”.
(is that another word for “stupid”?)
Peace,
Goran
Decaying power grid is the result of privatized power companies operating gor short term profit instead of long term maintenance.
A few points being an electrical engineer working on the Grid in various parts of N. America. First, one slight physics correction for an often held assumption. 60 Hz electrical energy does not travel at the speed of light. Only EM waves in a vacuum travel at the speed of light. EM propagation speed is attenuated by the medium. In most of the grid the medium is aluminum and v~0.5c. Still fast enough, but not full c. This is important for grid transient stability (and you really don’t want to see the math!).
True, the grid has been allowed to decay because it has been taken over by the “biz kids”. Where engineers built in redundancy and resilience the biz kids saw unused capacity and monetized it. Now we can’t take out parts of the grid for maintenance unless we really plan hard and twist a lot of arms. I know of some transmission lines where one is lucky if they can get an outage every 10 years, and then it is like a golf tournament shot-gun start with concurrent work going on at all locations at once. Ya, and then there is the logistics and resource problem to go along with that. The maintenance event is held like a jubilee.
Heat is a double whammy on the grid. As y’all can fathom, grid capacity decreases with an increase in temperature. Temp up, demand up, capacity down due to decreased cooling (lines, transformers, generators, et al). Big Mess. I’ve seen lawn water sprinklers spraying transformer cooling radiators in high temps to keep the units operational. That’s when I know we are in big trouble.
Also correct, most of the grid base load generation is designed to operate nearly continuous with marginal change in power levels. This is for both machine and fuel supply. Grid operators have gotten pretty clever managing variable generation sources.
A good mental model is to visualize the grid like a tarp being held up with strong elastic cords attached at each grommet. (THIS IS an experiment that can be tried at home). The grid has to be held constant at a level (voltage), the mechanism keeping the tarp level as objects (load) are added to it are the generator governors (power), and equally important, keeping the grid level and adjusting to variations are the reactive power (kind of like elastics and inertia). That’s pretty much it, just repeat this exercise a few thousand times over thousands of miles (kilometres) and voila! you have the Grid. Its a great party game. Have your friends stand around the tarp holding up playing The Grid (JJ). However, it is a good teaching tool.
Finally, I just got my IONIQ 5 and have a Level 2 charger at home. This is going to piss off a few people, but we will be getting a Time of Use (TOU) tariff for EV off-peak (LLH) charging at CDN$0.05/kWh. At my current 18 kWh/100 km this will work out to less than 1L/100km equivalent; CDN$ 0.90/100 km. At current gas prices that is >0.5L/100km.
Always good to hear from someone who actually knows what he is talking about. Thank you.