How to Avoid a Climate Disaster: The Solutions We Have and the Breakthroughs We Need

by Bill Gates

Fifty-one billion is how many tons of greenhouse gases the world typically adds to the atmosphere every year.

Zero is what we need to aim for.

today roughly 860 million people don’t have electricity.)

The world needs

to provide more energy so the poorest can thrive, but we need to provide that energy without releasing any more greenhouse gases.

I think more like an engineer than a political scientist, and I don’t have a solution to the politics of climate change.

The world is not exactly lacking in rich men with big ideas about what other people should do, or who think technology can fix any problem.

look for technology to fix it. When it comes to climate change, I know innovation isn’t the only thing we need. But we cannot keep the earth livable without it. Techno-fixes are not sufficient, but they are necessary.

once greenhouse gases are in the atmosphere, they stay there for a very long time;

In other words, “getting to zero” doesn’t actually mean “zero.” It means “near net zero.”

to avoid the worst climate scenarios, at some point we’ll not only need to stop adding more gases but actually need to start removing some of the gases we have already emitted.

Molecule for molecule, many of these other gases cause more warming than carbon dioxide does—in the case of methane, 120 times more warming the moment it reaches the atmosphere.

How do greenhouse gases cause warming? The short answer: They absorb heat and trap it in the atmosphere. They work the same way a greenhouse works—hence the name.

Most of it reaches the earth and warms up the planet, just as it has been doing for eons. Here’s the problem: The earth doesn’t hold on to all that energy forever; if it did, the planet would already be unbearably hot. Instead, it radiates some of the energy back toward space, and some of this energy is emitted in just the right range of wavelengths to get absorbed by greenhouse gases.

Why don’t all gases act this way? Because molecules with two copies of the same atom—for example, nitrogen or oxygen molecules—let radiation pass straight through them. Only molecules made up of different atoms, the way carbon dioxide and methane are, have the right structure to absorb radiation and start heating up.

In the mid-1970s, when we were just getting started, the temperature in Albuquerque went over 90 degrees Fahrenheit about 36 times a year, on average. By mid-century, the city’s thermometers will go over 90 at least twice as often every year.

Droughts will also threaten the Colorado River, which supplies drinking water for nearly 40 million people and irrigation for more than one-seventh of all American crops.

But California is a dramatic example of what’s going on. Wildfires now occur there five times more often than in the 1970s, largely because the fire season is getting longer and the forests there now contain much more dry wood that’s likely to burn.

In other words, by mid-century, climate change could be just as deadly as COVID-19, and by 2100 it could be five times as deadly.

Because climate change will have the worst impact on the world’s poorest people, and most of the world’s poorest people are farmers, adaptation is a major focus for the agriculture team at the Gates Foundation.

To have any hope of staving off disaster, the world’s biggest emitters—the richest countries—have to get to net-zero emissions by 2050.

oil is cheaper than a soft drink. I could hardly believe this the first time I heard it, but it’s true. Here’s the math: A barrel of oil contains 42 gallons; the average price in the second half of 2020 was around $42 per barrel, so that comes to about $1 per gallon. Meanwhile, Costco sells 8 liters of soda for $6, a price that amounts to $2.85 a gallon.

The key will be to make the clean approach as cheap—or almost as cheap—as the current technology.

Emissions from advanced economies like the United States and Europe have stayed pretty flat or even dropped, but many developing countries are growing fast. That’s partly because richer countries have outsourced emissions-heavy manufacturing to poorer ones.

What will happen as more people live like the richest 16 percent?

Even if the rich world could magically get to zero today, the rest of the world would still be emitting more and more.

At Breakthrough Energy, we fund only technologies that could remove at least 500 million tons a year if they’re successful and fully implemented. That’s roughly 1 percent of global emissions.

Passenger cars represent less than half of all the emissions from transportation, which in turn is 16 percent of all emissions worldwide.

making steel and cement alone accounts for around 10 percent of all emissions.

Tip: Whenever you hear “kilowatt,” think “house.” “Gigawatt,” think “city.” A hundred or more gigawatts, think “big country.”

Where do we need to focus our research and development spending, our early investors, and our best inventors?

wherever we decide Green Premiums are too high.

Getting all the world’s electricity from clean sources won’t be easy. Today, fossil fuels account for two-thirds of all electricity generated worldwide.

Today, the United States spends only 2 percent of its GDP on electricity, an amazingly low number when you consider how much we rely on it.

Changing America’s entire electricity system to zero-carbon sources would raise average retail rates by between 1.3 and 1.7 cents per kilowatt-hour, roughly 15 percent more than what most people pay now.

the electricity we store for nighttime use will cost us triple what we’re paying during the day—5 cents to generate and 10 cents to store, for a total of 15 cents.

Here’s the one-sentence case for nuclear power: It’s the only carbon-free energy source that can reliably deliver power day and night, through every season, almost anywhere on earth, that has been proven to work on a large scale.

The United States gets around 20 percent of its electricity from nuclear plants;

Of all the materials I’ve covered in this chapter, cement is the toughest case of all.

For cows, the ratio is highest of all: six calories of feed for every calorie of beef.

We need to produce

much more food than we do today, but if we keep producing it with the same methods we use now, it will be a disaster for the climate.

In a process called enteric fermentation, bacteria inside the cow’s stomach break down the cellulose in the plant, fermenting it and producing methane as a result.

there are roughly a billion cattle raised for beef and dairy. The methane they burp and fart out every year has the same warming effect as 2 billion tons of carbon dioxide, accounting for about 4 percent of all global emissions.

About half of poop-related emissions come from pig manure, and the rest from cow manure. There’s so much animal poop that it’s actually the second-biggest cause of emissions in agriculture, behind enteric fermentation.

There’s one last way we can cut down on emissions from the food we eat: by wasting less of it.

In the United States, it’s 40 percent.

transportation contributes only 16 percent of global emissions, ranking fourth behind how we make things, plug in, and grow things.

When you account for all these differences and look at the total cost of ownership, the Bolt will cost 10 cents more per mile driven than the Malibu.

With the price of today’s batteries, EV owners save money only if gas costs more than around $3 per gallon.