If you like understanding problems from an engineering mindset and want broad overview of how to solve climate change, How to Avoid a Climate Disaster is for you.

Climate and Global Health

Gates starts the book by discussing how he became involved with climate related efforts in the first place. Up until recently, the Bill and Melinda Gates foundation had focused exclusively on just two issues: global health, and U.S. education. Adding a third issue seemed like it would divert focus from the causes the foundation cared most about.

Ultimately, Gates came to the conclusion that these two factors are explicitly linked. If a family relying on subsistence farming isn’t able to grow their crops, they’ll face a big health crisis. Millions of people in India will die of heat stroke because they aren’t able to pay for air conditioning. Instead of thinking about climate as something that will cause certain communities to need to move as sea levels rise, we should think of it as a global health risk that will kill millions of people.

51 Billion Tons

The biggest number to know from the book is 51 Billion Tons. This is the number of effective CO2 tons that we push into the atmosphere every year.

During the pandemic, the number of greenhouse emissions went down by about 5%. We, however, need to get that number to zero.

Doing so won’t be easy! There are a number of areas that we generate emissions. And the ones often discussed in the news aren’t the biggest drivers of actual emissions.

  • material production (cement, steel, plastic): 31%
  • power generation: 27%
  • growing things: 19%
  • transportation: 16%
  • temperature control: 7%

This surprised me. Normally we hear all about “turning off the lights” or “carpooling” as ways to decrease our offsets. Instead, it’s new construction that accounts for the lion’s share of our offsets.

One other important thing to note about this number: certain gasses like Methane are approximately 100x more harmful than CO2. We normalize them to tons of CO2 just to ensure that we’re all speaking the same language.

Building replacements

Because concrete and steel production works via a chemical process, it’s incredibly hard for us to substitute it out!

What’s more… we can’t just stop building. Right now, we’re on track to build the equivalent of an additional NYC globally each month for the next 40 years.

Gates presents a few different startups which are solving this problem, some of which are essentially recycling emitted CO2 by sequestering it directly in the concrete.

Clean power and green premiums

When it comes to power consumption, there are different alternative energy sources we can leverage: solar, wind, hydroelectric, and nuclear.

But in each case, the most important thing to consider is the “green premium”. How much more would it cost to use electricity generated via renewable means, vs ones created via fossil fuels? If there exists any green premium, businesses are going to be reticent to switch their power consumption modes. That’s a key part of the role that regulation plays: we need to simultaneously change the incentives on some of these sources of electricity while also driving down the cost for places like China and developing nations.

Gates also breaks down the full energy capacity we’ll need to fully power the world:

  • worldwide: 5,000 gigawatts
  • the U.S.: 1,000 gigawatts
  • mid-sized city: 1 gigawatt
  • small town: 1 megawatt
  • household: 1 kilowatt

While it’s true that we have the technology to replace many of these energy sources, we don’t always have the economic incentives, or the space! Fossil fuels have an incredible energy density of 500-10,000 watts per square meter, while solar can only get to about 100 watts per square meter. In order to correct the cost curves, we’ll also need to correct the “space curves” as well.

Natural vs engineered carbon removal

A key point that my co-founder Peter has mentioned again and again is the difference between natural carbon removal vs engineered carbon removal. It’s something that Gates mentions as well.

Natural carbon removal is probably what we all heard about in school growing up: the way to save the climate was to plant a lot of trees! After all, plants help remove CO2 from the atmosphere naturally!

It turns out there are a few problems with that. The first is that trees don’t last forever, they might be logged, cut down, or burned. The second is that trees can actually increase temperature levels in areas where snow would naturally reflect light. Finally, even if we wanted to only plant trees, offsetting the current number of emissions would require a massive amount of space.

The result is that we should be wary of any organization that promises to reduce atmospheric carbon simply via forestation.

The other option is Engineered carbon removal. These organizations (like Charm Industrial!) work by measuring the carbon they are removing from the atmosphere, and then taking special measures to sequester it underground or in soils. Right now, the leading forms are underground sequestration, and direct air capture.

Tech alone won’t do it

The book ends with noting that there are a lot of important levers we need to move to drive change… it won’t come from technology alone. Notably, the government needs to step in to both provide regulation and to broadcast certain demand for different markets.

One thing that seems obvious in retrospect is that both the government and consumers have to “lead the way” here a little bit. Tesla and Toyota managed to prove that there is a large and growing market excited for electric cars. That demand pushed more and more car makers to produce their own cars, which gave governments like California conviction in setting deadlines for enforcing all-electric vehicles.