Solomon GoldsteinRose How much clean electricity do we really need TED Countdown
Hello, how is everyone feeling?
(Cheers)
Are you ready to solve climate change?
(Cheers)
Good.
Do you know what a pettawat hour is?
Yeah, it’s a unit of energy like
kilowatt hour or megawatt hour.
I’ve been a climate activist since age 11
and I studied engineering,
and so I was familiar with those terms.
Kilowatt, megawatt,
even gigawatt and terawatt.
But I had never heard of a petawatt hour
until I wrote a book
on climate change solutions.
That’s because it’s so big.
But that’s the scale I want to talk about.
A petawatt hour is a trillion
kilowatt hours.
And today the world generates
about 25 trillion kilowatt hours
of electricity each year.
Most of that is from
fossil-fuel power plants,
and the dominant mindset
is that we have to change
the current electricity system
by replacing those fossil-fuel plants
with clean generation by 2050.
Well, over one third of our electricity
generation is already clean,
mostly from hydro and nuclear,
along with wind and solar,
and clean generation is growing.
Projections based on current policies
around the world show
that we are on track
to have about 25 petawatt hours
of clean electricity generation in 2050.
That’s two and a half times today’s
amount of clean generation
and equal to today’s total generation.
So this is great.
We can replace all our fossil fuel plants,
have a clean version of today’s world,
walk away, we’ve solved climate change.
Thank you very much.
Oh, but I did forget
one tiny little detail.
We actually need five times that much.
To be clear, we need
and we’re on track to have
two and a half times
today’s amount of clean generation
to switch to a clean version
of our current electricity system.
But changing the current
system isn’t enough.
We need five times that,
all of it clean,
or 12 times today’s clean
electricity production,
to actually avoid the worst
impacts of climate change.
Can I repeat that?
To avoid the worst
impacts of climate change,
we have to multiply today’s clean
electricity production by 12 times.
There are four main reasons
we need that much.
First, let’s keep in mind scientists’
goalpost for addressing climate change:
achieving net-negative emissions
globally by around 2050.
Most of us know that to do so,
we’ll have to electrify
a whole range of vehicles,
heating systems
and some industrial processes.
Electric equipment is more efficient
than fuel-based equipment.
So electrification actually lowers
total global energy demand,
but it increases
electricity generation needed.
In our current energy world,
electrifying 60 percent,
which is ambitious,
would add enough demand
that we would need roughly
40 petawatt hours
of total electricity generation by 2050.
Second, it’s not OK to simply replace
today’s world with a clean version.
In today’s world,
over 700 million people
don’t have access to electricity.
Billions more have access
only to small amounts
or to unreliable supply
that often cuts out.
Energy demand in rich industrialized
countries will grow more slowly
over the next few decades
with increased efficiency.
But energy demand in developing countries
will continue to grow dramatically,
especially if we can make
electricity cheaper.
This is good.
Energy access is lifting people
out of poverty,
driving access to education,
commerce, health care
and lower birth rates.
Both for moral and practical reasons,
those of us in richer countries need to
realize that addressing climate change
will necessarily center
on a massive expansion of energy access
in developing countries.
So electricity generation
will have to grow even more
and get cheaper
to accommodate
global economic development.
Based on projections of global
development by 2050,
generation needed rises to 60
petawatt hours per year.
The third reason is a bit more debatable,
but it needs to be talked about
more in public discourse.
It has to do with the fact
that not everything
can be electrified by 2050.
Long-range airplanes, for instance,
are still going to need the energy
density of a liquid fuel.
Similar for some industrial processes.
Now, many models waive this issue away
with two overoptimistic assumptions:
that all those factories continue burning
fossil fuels but use carbon capture,
which costs extra and will only happen
where governments mandate it,
and that all those long-range vehicles
use sustainable biofuel,
which is only sustainable
if every supplying country,
and its local governments,
fully enforces strict
standards for biomass
to avoid deforestation and other impacts
that could increase
emissions from agriculture.
Some amount of carbon capture at factories
and sustainable bioenergy
will absolutely be part of the picture.
But I’ve been in politics,
and I am sure that we should plan
for imperfect policy.
And that means we need to plan
for building even more
electricity generation.
We can use this additional generation
to synthesize fuels
that are truly carbon neutral
or entirely carbon free:
hydrogen, ammonia,
synthetic jet fuel and others.
This is a much rougher estimate,
but to be confident of minimizing
climate change impacts,
we should aim to push our line
up to around 90 petawatt hours per year.
Finally, the fourth reason
is that we need not only net-zero
but net-negative emissions in 2050.
There will be some non-energy emissions
that remain, especially from agriculture.
And we’ll have to pull CO2
from the atmosphere
to make up for those.
But we also need to use all
our possible carbon-removal methods
at their maximum capacity
to remove more CO2 each year,
getting as far as possible
into net-negative emissions,
drawing down levels of greenhouse
gases in the atmosphere
to eventually restore a stable climate.
One of the carbon-removal methods
we’ll have to use is direct air-capture:
arrays of fans filtering CO2 from the air.
And doing enough of this to restore
safe temperatures within decades,
not centuries,
will require yet more
electricity generation.
Again, the exact amount depends
on quite how ambitious we’re able to be.
But for a comfortable rate
of carbon removal,
we would need perhaps 120
petawatt hours per year total.
So roughly five times today’s total
global electricity system,
12 times today’s clean
electricity production,
and that can actually achieve
net-negative emissions globally.
And there’s a bonus reason to consider.
Because clean electricity
is going to power so much
of the rest of the transition:
electrification, global development,
synthesized fuels and sequestration,
to achieve net-negative emissions by 2050,
we should really build as much as possible
of that new electricity generation
at the beginning
of the transition, starting now.
This will make sure
that clean electricity is abundant
and cheap soon enough
to still leave time for all of the other
transitions that rely on it
to fully roll out by 2050.
And when we talk about abundant
and cheap electricity,
we’re talking about eliminating
poverty faster,
powering access to water desalination,
strengthening medical supply chains,
so much more.
Decarbonizing and scaling
electricity generation
will also be the biggest global
development project ever.
So if we want to avoid
the worst of climate change,
we need to discard that dominant mindset
about merely replacing
fossil fuel generation.
My point is, that misses the scale.
Our project is not changing
the current global electricity system.
Our project is building a new
global electricity system.
Political action that tinkers around
within the current system
will never get us
where we need to be by 2050.
Arguments over which sources of clean
electricity we should use are unhelpful.
We need all of them:
hydro, solar, wind,
nuclear, advanced nuclear,
advanced geothermal,
mandates for carbon capture
on remaining fossil plants.
If you look at the potential rates
of addition for each of these,
you’ll see we need everything
as much as possible
and we may still fall short.
It’s not changing the electricity system.
It’s building a new electricity system.
One five times bigger
than today’s total system
and 100 percent clean.
As fellow youth activists often say,
the project is much more comparable
to the World War II-era manufacturing boom
than anything the world has done since.
Building new things
that we’ve barely ever built before,
in massive amounts,
to create a new system entirely.
In fact, this mindset goes beyond
electricity-generation itself.
Many people are wary
of ambitious climate action
because they see the project as changing
the familiar current world.
That’s not it.
Addressing climate change
means building a new world.
A world in which energy is healthier,
doesn’t pollute the air we breathe
and where it’s cheaper and everyone
globally has access to it.
A world with higher incomes,
longer and better lives,
greater equality.
A better world.
Thank you, and let’s make it happen.
(Applause)