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Understanding Electric Power and Power Outages- Texas Edition Winter 2021

February 22, 2021
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Texas put millions of people in the dark. There is a lot we can learn so we don’t do that again. Some of the lessons are obvious, and some are subtle. Here are a few of the key ideas. The blackouts of mid-February showed us that not all powerplants are the same. Electrical power source have important differences. The users of electricity have important differences too. Also, the energy we use has to come from somewhere every second. The supply and demand for power will match or the grid will collapse.

Typical changes in electrical demand

This cold snap wasn’t a surprise. Utility operators saw the cold weather coming. This wasn’t a localized phenomenon affecting a small area either. There were projected record low temperatures forecast over several states and parts of Mexico. That made it hard to get power from one region and send it to anther. Everyone was facing the same situation. We were all running our gas heaters, our electric space-heaters, and our fans.

The demand for energy is never constant. It varies from month to month, day to day, and even second to second. You have heard and seen it yourself if you’ve run a generator to power your home during an emergency. We think we are only running one light as we try to conserve power. Then, the inside of our refrigerator heats up a fraction of a degree and the refrigerator turns on automatically. We forget that our laptop and cell phone chargers are drawing power. Our electric water heater cycles on or our well pump turns on, and suddenly the load is too large. Our generator trips its circuit breaker.

Poof. We’re sitting in the dark. On average, we might have had enough power to run our home, but we didn’t have enough power when a number of variable loads turned on at the same time. Utility operators have the same problem on a vastly larger scale.

The load changes from second to second, and we can only make so much power. To make things more complicated, we can only transport so much power from region to region. Some powerplants run at an even power output. Some powerplants cycle up and down to accommodate the uneven demand. Other powerplants come on and off rapidly to keep the grid stable as the power supply fluctuates. Yes, wind and solar power fluctuate up and down each second and they need conventional generators that can make up the difference at a moment’s notice. Even solar and wind are regulated by the grid rather than being self-regulating as they match frequency, voltage, and phase. Supply has to meet demand, everywhere and at all times. That is easy to say, but hard to do.

That is why we don’t count on solar power to meet our electrical demand. The peak demand might come at night, on a cloudy day, or on a morning when the solar panels are covered with ice and snow. We can’t count on wind power either. The peak demand might come when the wind is still or come after a winter storm when the wind turbine blades are covered in ice.

Removing ice from turbine blades. Image from pergelator.blogspot.com

It might seem that wind and solar are “free” but they aren’t really free at all. At best, they can cut the fuel bill from existing generators a few days of the year. We can’t count on them.. ever. Well, we could depend on wind and solar to give us electricity, but depending on power we don’t have means we’re going to sit in the dark. I was without power and I didn’t like it.

Utility operators have a pretty good idea of how much power they will need. They look ahead at the weather and ask major industries to cut back their power use during peak demand. You and I do this as well when we don’t run our clothes dryer at 2 in the afternoon on a hot day when everyone is running their air-conditioner. That only takes us so far in reducing our demand for power.

Operators reduce the peak demand to keep from crashing the entire power grid. They can’t overload powerplants. They can’t overload electric lines as they try to balance power demand in one area and power supply in another. The coal, gas, and nuclear plants provide stability for the entire utility network. Utility operators drop part of the load so their powerplants don’t trip and go offline.

That means a few thousand of us at a time are without power in each city. That is what operators are supposed to do, but they didn’t. A few major powerplants tripped offline as the demand for power in Texas grew too large. That was a mistake. The reduced supply dropped hundreds of thousands of us into the dark. It can take days to get a major powerplant started. Fortunately, these plants came back online quickly as operators realized their mistake.

Running a power grid isn’t as easy as it seems. We think we want to drop industries so we can heat homes. We think we want to drop power in rural areas and keep power on in the cities where lots of people live. Reality is more complicated than that.

Our cities depend on industry and rural areas. Texas utility operators dropped power to some major oil and gas producing regions. That knocked natural gas pumping stations off-line. The pumping stations were not electric, but the communications and monitoring equipment in the pumping stations depended on utility power. Maybe the valves and lubrication systems used utility power as well. Shutting down those pumping stations reduced natural gas supplies during a cold snap. Even your gas furnace needs electrical power to run. Some of your natural gas fired generators certainly do.

Maybe those pumping stations should provide their own electricity and be power independent. They could, but at a cost. Money spent on providing greater reliability is money that isn’t spent on finding new supplies of natural gas. Adding electrical generators to these pumping stations will cost money and the price we pay for natural gas will go up.

We traded low cost for reliability. In hindsight, it might have been a good idea most of the time, but it was a bad deal on a February night in 2021. Most of us would gladly have spent a little more every day to keep the lights on at night.

We will have cold weather. Operators will make mistakes. We can, and we should, plan for both. Of course, we don’t have to think ahead. We don’t have to invest in reliable energy, but that leaves us sitting in the dark. If you’ve tried it, then tell me how it felt.
~_~_

I gave you 1000 words. Please share them with a friend who needs them. RM

One Comment leave one →
  1. February 22, 2021 12:28 pm

    Many of those natural gas plants that were cut off in the rolling blackouts supplied natural gas to electrical generating plants. Thus by cutting them off electrical generators were cut off too reducing the available power. This is what I call a “cascade failure”. It isn’t that one thing went wrong. It’s that a number of things went wrong and some of them caused other things to go wrong compounding the problem. If the gas plants are not self sufficient, they should at least be isolated from rolling blackouts somehow.

    Liked by 1 person

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