Why this article is important:
- The article frames climate change as a process control problem, making it directly relatable to how process engineers think.
- It stresses that money, not education or legislation alone, must be the manipulated variable, highlighting the need for clear, impactful control strategies—a concept central to process engineering.
- It uses economic analysis similar to how engineers assess ROI and operational costs, showing how financial levers can drive systemic change just like tuning a process loop.
If global warming was a temperture control loop, how could a process control engineer select and control the manipulated variable for that loop?
Statistics show 10% of Americans don’t believe in climate change and favor using even more fossil fuels. Their slogan is, "Drill, baby, drill!” They believe fossil discoveries will rise, consumption will drop, and even if they don’t, we should just leave this problem to future generations to solve. It’s a small minority, but another 15% are undecided or have some financial interest in maintaining the status quo.
We know that the easiest way to change human behavior is by impacting wallets. Therefore, strong financial motivation is needed to stop us from doing what emperor Nero did—playing the fiddle while Rome burned.
We’re beginning to accelerate switching to a sustainable and clean energy economy. One indicator is that wars over oil and minerals are starting. They’ll become much worse as we near the bottom of the resource barrel. Another indicator is that use of solar- and wind-based electricity use exceeds all others, and their costs are below all other sources and dropping (Figure 1).
I have mixed feelings about the future. On one hand, the time available to fix things is running out. I was on one of the 13 green energy development teams set up by President Jimmy Carter 46 years ago. We took for granted that in a couple of decades global warming would be stopped.
It was a time when 39 solar panels were placed on the roof of the White House and our teams (directed by military officers) came up with methods to switch to renewable energy. Now, Carter's solar panels are gone and carbon dioxide in the atmosphere has reached the point where—if the gas wasn’t transparent—the planet would be dark.
However, I have mixed feelings because, after the coming, four-year period of "drill, baby, drill,” our society will see the consequences of inaction, face reality, and the slogan will turn into "Switch, baby, switch!"
Switching the manipulated variable
To design a "climate control loop," the first task is selecting a powerful, manipulated variable that brings in the controlled variable (human behavior) to serve the loop's goal. The manipulated variable isn’t education or legal or political action. It’s simply money. We must create conditions that will make switching to renewable energy a financial benefit to voters. It will happen when we stop treating the atmosphere as a free garbage dump. We must make people understand that, just as we pay for removing solid waste from our homes or disposing of our wastewater, we must also pay for dumping harmful gases into the atmosphere.
Today, the global yearly emission of carbon dioxide equivalent gases is 40 billion tons. I estimate that charging a fee of about $20 per ton of harmful emission for two decades would be enough to finance the conversion to a carbon-free age. Compare this sum to how much we pay our municipalities for removing a ton of garbage or wastewater from our homes.
There is another way to look at it—calculate the present cost of passivity or estimate future costs of idleness, if inaction continues. Compare it to the financial and emotional costs of restoring the damage that Los Angeles suffered from a single wildfire ($0.25 trillion). Naturally, this wasn’t the only disaster in which climate change played a major role. After all, whole regions are already becoming unlivable. The total global damage was probably already more than 10 times that of the L.A. fire, or more than $2.5 trillion. Estimating the cost of restoring all the damage that climate change will cause worldwide in the coming years is anybody's guess.
Looking at it as a cost-benefit analysis, if the cost of stopping greenhouse gas (GHG) emissions is $20 per ton, and 40 billion tons are being emitted yearly, that cost is $0.8 trillion, or three times the damage in L.A. or about 0.5% of global gross domestic product (GDP).
Get your subscription to Control's tri-weekly newsletter.
Controlling solar-hydrogen storage
Solar energy is a clean, inexhaustible, safe and free energy source. It directly fuels life on Earth by providing energy for plants, which produce hydrogen from water in the ground and combine it with carbon in the air to form complex moleculesthat provide energy for us. Millions of years ago, at the end of this cycle, the remains of plant and animal life collected in the planet’s crust to form fossil fuels, which can be viewed as stored solar energy. In a carbon-free energy economy, we’ll stop using this storage and will switch to the directly using solar energy.
Because solar energy is available only intermittently, continuous use requires storage. We must not only stop burning fossil fuels, but also prepare large energy storage facilities to supply our energy when the sun isn’t shining. The most common ways of storing energy is taking advantage of gravity (pumped hydraulic) or electrochemical (battery) methods, but both have serious limitations (Figure 2).
Building pumped hydraulic storage is possible only in mountainous regions, while battery storage is limited because we’ll run out of materials required to build them. Meeting global energy storage needs with batteries in a "solar-hydrogen age" would require 100 times the amount of minerals used for that purpose today. For these reasons, we must start using chemical storage (solar hydrogen).
The bottom line
Today, only about 4% of hydrogen produced is green (made from water by solar electrolysis), while 96% is produced from hydrocarbons by carbon-emitting processes. Also, hydrogen is expensive. Its storage technology has changed little in the last half-century, and builing the infrastructure needed for its widespread use, such as converting natural gas distribution to also handling hydrogen, has barely started.
Hydrogen use in transportation has made progress, but the number of fuel-cell electric vehicles on the roads is less than 100,000, mostly buses and trucks. there’s more substantial use of hydrogen in rocket and space exploration because its low weight and density are keys to space travel. The use of hydrogen by the military as the fuel for drones is also increasing because it’s quiet and hard to detect.
Hydrogen can also fuel for sensible and ego-driven projects of powerful people. King Salman of Saudi Arabia is throwing a half-trillion dollars into building the Line City in the Sahara. Elon Musk is burning immense quantities of hydrogen for space travel and, eventually, to build a city on Mars. Whether it’s Salman in the Sahara or Musk on Mars, these billionaires and trillionaires remind me of Nero.
