The Invisible Trillion · No Going Back

The Number That Should Surprise You

Per-person energy use in the United States has been roughly flat since about 1973. In some years it has gone down. The 2026 family uses almost exactly the same amount of energy as the 1975 family.

But look at what that energy does now, compared to 1975:

The 2026 refrigerator is twice as large and uses about one-quarter the electricity.
LED bulbs use about one-tenth the energy of incandescent bulbs.
Cars go about twice as far on a gallon of gasoline.
Houses are better insulated by a factor of two or three.
A 2026 laptop uses a tiny fraction of the energy of a 1975 mainframe while being roughly a million times more powerful.
A modern natural gas power plant converts fuel to electricity about twice as efficiently as a 1975 coal plant.

What has happened, quietly, over fifty years is one of the great engineering achievements in human history, and almost nobody talks about it. We are doing vastly more with the same energy. The reason our per-person energy use hasn’t exploded is that every device, every building, every vehicle, and every power plant has gotten dramatically more efficient, roughly in lockstep with our appetite for more of everything.

This is a fact. It is not an opinion. You can look it up. The U.S. Energy Information Administration publishes the numbers every year. Per-capita energy use peaked around 1978 and has drifted downward since.

If you have been told — online, in the press, or by a well-meaning friend — that humans are using more and more energy per person and that the trajectory is unsustainable, the first part of that sentence is factually wrong in the rich countries, and it is worth knowing why you heard it anyway.

(The second part — about sustainability — is a real question, and we’ll get to it. But it has almost nothing to do with per-person energy use in America, and almost everything to do with the fact that there are a lot more people now, and a lot of them reasonably want refrigerators.)

The Thought Experiment

Go back to the time machine question at the start of the chapter.

Would you give up refrigeration? Really think about it. No refrigerator means no dairy past a day, no meat past a day, no leftovers, no frozen anything. It means your diet in February is root vegetables, grains, and whatever meat you can salt or smoke. It means food poisoning as a regular event in your life. It means that when your two-year-old gets diarrhea, which happens more than you’d think in a world without refrigeration, there is a real chance she dies of dehydration, because that is what used to happen and that is why infant mortality was what it was.

Almost no one, confronted with this honestly, chooses to give up refrigeration.

Would you give up hot water on demand? Really think about it. A weekly bath, heated on the stove, shared by the whole family. Laundry as a full day of labor, once a month. Washing your hair as a production involving a basin and a kettle. This was the normal human condition until about 1920 in the rich countries and is still the normal condition for about a third of humanity.

Almost no one, confronted with this honestly, chooses to give it up.

Would you give up lighting after dark? Your productive day ends at sunset. In December, that’s 4:30 PM. Reading by candlelight is genuinely hard — the light flickers, your eyes strain, and the candles smell. Most people in 1725 went to bed around 8 PM in winter and got up at dawn. Their lives were shaped by the sun in a way ours aren’t, and almost no one, offered the trade, wants to go back to that life.

Would you give up air conditioning? This one is more interesting, because it splits by where you live. Your grandparents in Boston probably didn’t have AC and were fine. Your cousins in Phoenix cannot live without it — literally cannot, because the summer temperatures there, which are rising, are now lethal to elderly and sick people within a few hours of exposure. In 1980, about 55% of American homes had AC. Today it’s about 90%. This is the change you can most easily feel within a single lifetime, and it is the one most directly driven by a climate that is itself changing.

Would you give up the internet? Sit with this one. Really. Your whole social life, most of your education, most of your entertainment, most of how you find out what’s happening in the world, and — if you’re honest — most of the way you form your opinions about things like data centers and chips.

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