[MUSIC]
It was the hot summer of 2019.
I was at the Cannes Film Festival, attending a world premiere.
And Leonardo DiCaprio was clapping for me.
[LAUGH] Yes, I know.
Well, not just for me.
As you may know, Leonardo DiCaprio is a UN messenger for
peace with a special focus on climate change.
His project at Cannes was a new documentary on global warming,
Ice on Fire.
Instead of the usual doom and gloom you might expect,
his documentary took a new approach.
It showcased the work of real scientists measuring CO2 emissions in Hawaii.
Researchers monitoring methane leaks in Alaska.
And engineers inventing technologies that fight climate change.
And I was one of those engineers.
The technology I helped create and develop,
called direct air capture was featured in Leonardo's documentary.
And yes, I call him Leonardo, we're close.
While I'm not here to promote Ice on Fire, you should probably still check it out.
Rather, I'm here to talk to you about what I expect I will be doing for
my entire life.
I'm here to talk to you about the good, the bad, and
the absolute necessity of direct air capture.
As the name suggests, direct air capture uses machines to
capture carbon dioxide, or CO2 from the air.
These machines use air which contain 0.04% CO2,
and deliver 100% concentrated CO2.
The pure CO2 can be used as a chemical building block for
other materials, like plastics or synthetic fuels,
but the vast majority of it must be stored underground for good.
How do these machines work?
There are several technologies out there, but
they all have chemistry at their core and
they all have the same goal, to capture and remove carbon dioxide from the air.
But let's look at it step by step.
And I am an engineer, so I will be going into all the gory details.
In a first step,
big fans bring air in contact with the filter that you can imagine as a sponge.
The filter continuously and
selectively takes up CO2 from the air until the sponge is saturated.
In a second step, the CO2 is unloaded from the filter, either using heat or pressure.
This is where we squeeze the sponge so that we can use it again.
Once free of CO2, the filter can be ready for another loading and unloading cycle.
The final result is pure CO2 from the air and better yet,
atmospheric air with reduced CO2 concentrations.
Hope you're still with me and that you have a good idea of how this all works.
Now you might be wondering,
well there's a lot of air out there and not only 0.4% CO2.
Well, direct air capture sounds like looking for
a needle in a haystack, why bother?
To understand why, we need to look at the current state of climate change and
here the doom and gloom are frankly justified.
The world has emitted so much CO2, that most climate models show
that global warming cannot be kept to the original 1.5 degree temperature limit.
The good news, there are current efforts underway to decarbonize the economy.
Electric cars, solar panels, windmills.
These will help reduce the amount of CO2 we put into the atmosphere.
The bad news, there is no off switch.
We cannot stop emissions tomorrow, even if we wanted to.
This can only be a gradual process.
So we need direct air capture.
And this is where direct air capture comes into play.
To remove historic legacy emissions and
to help our increasing efforts of decarbonization,
we need direct air capture with CO2 storage underground so
that all the excess CO2 from the atmosphere is stored away for good.
I want to acknowledge for some of you,
putting CO2 back underground sounds like a worrying prospect.
People ask me, is there space underground?
Is it safe?
Will the CO2 just leak back out?
That's because we mostly imagined Earth as a solid ball, dense and
compact, but that's not the case.
We know there's space for
the CO2 underground because that's where it came from in the first place,
from natural gas, oil, and coal, that we've mined and burned.
So what are the benefits of direct air capture?
What does this do for us?
First, we can control how many machines we build and how fast we build them.
Second, their efficiency and their performance can be measured, and
we can easily track and certify how much CO2 we've removed.
This technology gives us control over our climate change mitigation strategy.
But why do we need direct air capture, if we have trees and other natural solutions.
And here it's not an either or we need both.
We need as many large forests as possible to capture CO2 and
keep it in the carbon natural cycle.
Carbon natural cycle already relies on soils,
forests, and the oceans to keep CO2 out of the atmosphere.
But that's not enough, forests cannot be large enough,
to keep all the excess CO2 that we have.
Worse even is that climate change and human behaviour affect forest and
today we are losing more trees than we're adding.
So we need direct air capture,
something that even the critics of this technology can acknowledge.
And what do the critics say?
Some say CO2 removal or technological carbon removal should be our last resort.
And it is, it is one of the last few lifeboats we have, and we should use it.
And by the way, lifeboats are good.
I suspect Leonardo himself would have used one on the Titanic had it been available.
Other critics worry about the moral hazards of this technology.
Especially problematic is if companies or governments use the mere possibility
of direct air capture as an excuse to postpone CO2 emission reductions.
But let's be clear, the pledge to remove carbon dioxide in the future
should not be allowed to embolden emitters today.
And this is where we need good policy.
I'm the first to admit that engineering and
building direct air capture machines, my life's work, is only but
a small piece of what is needed to undo decades of reckless CO2 emissions.
But this is why I'm here today, to ask for your help.
Direct air capture needs you as well, to find the right policies,
the right financial incentives, and even the right regulations.
And while I cannot promise too much glory or applause, at Cannes or
otherwise, I can promise you it will be Earth changing.
Thank you.
>> [APPLAUSE]
[MUSIC]