In 2016, Bill Gates shared a simple equation to understand how we can solve climate change by eliminating carbon emissions from energy.
This equation is incredibly useful. It cuts out the noise and distils the problem down to the basic elements. Importantly, it explains what we need to do to achieve a carbon-free energy future.
Here it is.
P x S x E x C = CO2
Now, let's break this down.
On the right hand side, we have CO2: that's the greenhouse gas we emit into the atmosphere. We want this to be zero.
On the left hand side, we have four inputs. Multiplying these four inputs gets us to our total carbon emissions.
P = how many people are in the world.
S = services used by each person;
E = energy needed to power each of these services; and
C = the carbon dioxide created by that energy.
Our path to a carbon-free energy future
For CO2 emissions to be zero, we need one of the inputs to be zero.
So let's go through them.
Population (P) will increase. We're projected to reach 9 billion people by 2050.
Services (S) should increase. More services will increase quality of life, especially in developing countries.
Energy (E) needed to provide services can go down. There are promising developments in energy efficient technologies to reduce emissions.
But this won't go to zero.
This leaves carbon dioxide (C) created by energy as the remaining option. This is our path to a zero carbon energy future.
This is where we need to transition away from fossil fuels and invest in carbon-free energy like solar, wind, and hydrogen.
This equation shows us that achieving a carbon-free future is impossible if we don’t invest in clean energy sources. We can’t rely on improving energy-efficiency to prevent climate change.
However, if we achieve this, it gives us hope that we can sustain a planet with more people and more services without warming the planet. It shows us that a future that improves the lives of people in developing countries through more services does not conflict with a future that prevents our planet from irreversible climate change.
As Bill Gates says, "a cheap, clean source of energy would change everything."
Tackling climate change will depend on developing a clean source of energy.
It’s unlikely that we can prevent climate change without this.
You can read more from Bill Gates on this here.
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