Climate change is real. Carbon neutral is vital to survival of humanity. But news coverage has recruited the Texas power crisis to support issues general to climate change, including pros and cons of renewable energy, and the threat of disasters in other geographic areas. This is misdirection; this disaster was made in Texas and stays in Texas.
Refer to (Climate Central) The Fuel You Use For Heating Depends on Where You Live. In the southeast, which includes Texas, electric heating is most common. In all other areas, fossil fuel predominates. Texans prefers electric heating because:
- It is cheap to install.
- The need is occasional, so in the south, resistive electric heating, the most wasteful method of heating short of setting your house on fire, can be justified.
- In areas further from the Gulf coast, at minimal additional manufacturing cost, an air conditioner can also function also as a heating device, a “heat pump.”
Let’s do some environmental arithmetic. Electricity is energy, just like heat, except for one crucial difference: The entropy of electricity is zero, which means it can be converted into heat with 100% efficiency. The reverse is not so. At a fossil fuel power station, fuel is burned to create heat, which is a form of energy. In Texas, natural gas is the fuel. The average efficiency of a gas plant is 45%, held down by steam turbines. Newer internal combustion gas turbines from GE and Siemens hit 63%. (IEEE Spectrum) Gas Turbines Have Become by Far the Best Choice for Add-on Generating Power.
The industry standard approximation for transmission loss to your home is 6%. Resistive electric heating is a climate change nightmare. When you plug in a resistive electric heater, when sometimes you can see a coil glow cherry red, you are burning almost twice as much fossil fuel as a home gas heater. Not exactly twice, because home gas heaters lose some energy in vented exhaust gases. In the 1960’s, half the heat went up the flue. Now the loss of home gas heat is down to about 15%.
Any Texan who can afford A/C buys an A/C heat pump combo. Heat pumps have a trick. By reversing the Carnot cycle, a heat pump appears to produce more heat than the energy equivalent of the electricity required to run it. Down to an outside temp of 40F, this can be 3X as much. This neatly balances out the almost 2/3 losses of converting fossil fuel to electricity and transmission to your home.
As the outside temperature drops, the heat pump loses efficiency. At 5F, a non-specialty A/C heat pump combo supplies only as much heat as the electricity equivalent required to run the compressor. As the temperature continues to drop, the demand on the power grid exceeds summertime peaks. At extremes, a resistive electric heater actually becomes more efficient!
North of Oklahoma, which participates in the U.S. national grid, the climate is too severe for an A/C-heat pump combo. Specialty cold weather heat pumps can work far north, but make sense mostly where there is no gas grid. So the Texas Power Grid Disaster is unique to Texas. Disasters occur everywhere, but the only lessons we can take are general. Those that apply everywhere:
- Safety culture. Boeing, FAA, Space Shuttle Challenger, Richard Feynman, and Safety Culture. And then meditate on:
- Reliance on centralized systems. Texas isolated their grid, and it bit them. But the Texas grid is itself a centralized system.
- The statistical long tail, showing up from time to time as an unusually deep PolarJet, which set the whole thing off. While the cold snap is not by itself as rare as a Black Swan, the coincidence of other factors, including COVID-19, is very swanish. Catastrophe Theory for Dummies Part 1 and Catastrophe Theory for Dummies Part 2.
- Inevitable human contribution, the Energy Reliability Council of Texas, which by free-market competition shaves supplier spare capacity. ERCOT comes last, because the entire Texas system compounds the consequences of irresponsibility, including the human kind.
Why the Texas disaster is special:
- An isolated grid subject to wintertime electricity consumption peaks that can exceed summertime.
- Circumstances that almost uniquely favor electric heating in a region of climate extremes. In Texas, part of Tornado Alley, warm Gulf flows and cold fronts driven south by the jet stream are in constant opposition.
If you’re outside of Texas and looking for lessons, pick from the first list and ignore the second. Now what about climate change? (UCAR Center for Science Education) Why the Polar Vortex Keeps Breaking out of the Arctic states
Typically, a large difference in temperature between the air of the polar vortex and the air in the mid-latitudes drives the polar jet stream. However, the Arctic is warming faster than other areas of the planet… “Ironically and counterintuitive to many, the strong polar vortex can be linked, in part, to warmer temperatures.”
It’s probably true, yet due to the complexities of turbulent systems, it’s not good for argument. Ignorant rebuttals are just too easy:
- Great Hurricane of 1780, likely the strongest hurricane for which any records are available.
- Great Blizzard of 1888, the most severe to affect the eastern U.S.
- Tri-State Tornado of 1925, the most deadly U.S. tornado. NOAA summary.
Texans have a saying, “Don’t mess with Texas.” This did not stop the Fickle Finger of Fate. What can the rest of us distill?
- Everywhere in the U.S., we rely on systems that rely on heroics, or at least diligence, to avoid disaster.
- Highly redundant systems can hold the Fickle Finger at bay, maybe long enough to fix the problem before disaster.
- Vulnerabilities are tied to locale. There are no general solutions.
Since I live in the mid-Atlantic, I have a specific insight for gas heat. When Hurricane Sandy struck, we were without power for 3 days. Our home gas heat hot water system requires about 500 watts of electricity to run the pumps, fans, thermostats, relays, and microprocessor. No electric, no heat. I made it through with a generator.
A Stirling engine is a sealed system that requires only a hot surface and a cold surface to work. A typical furnace room has both. The engine could be part of a furnace setup, turning a small electric generator. With a compatible furnace, a Stirling engine could produce enough power to run a heating system at reduced output.
Stay warm. Some like it hot.