Thank you very much.
When I was a boy,
my parents would sometimes take me camping in California.
We would camp in the beaches, in the forests, in the deserts.
Some people think the deserts are empty of life
but my parents taught me to see the wildlife all around us:
the hawks, the eagles, the tortoises.
One time when we were setting up camp,
we found a baby scorpion with its stinger out,
and I remember thinking how cool it was
that something could be both so cute and also so dangerous.
After college, I moved to California
and I started working on a number of environmental campaigns,
I got involved in helping to save the state's last ancient redwood forests
and blocking a proposed radioactive waste repository set for the desert.
Shortly after I turned 30,
I decided I wanted to dedicate a significant amount of my life
to solving climate change.
I was worried that global warming would end up destroying
many of the natural environments
that people had worked so hard to protect.
I thought the technical solutions were pretty straightforward -
Solar panels on every roof, electric car in the driveway -
that the main obstacles were political.
And so I helped to organize a coalition
of the country's biggest labor unions and biggest environmental groups.
Our proposal was for a 300 billion dollar investment in renewables.
And the idea was not only would we prevent climate change,
but we would also create millions of new jobs
in a very fast-growing high-tech sector.
Our efforts really paid off in 2007,
when then-presidential candidate Barack Obama embraced our vision.
And between 2009 and 2015, the US invested 150 billion dollars
in renewables and other kinds of clean tech.
but right away we started to encounter some problems.
So first of all, the electricity from solar rooftops
ends up costing about twice as much as the electricity from solar farms.
And both solar farms and wind farms require covering a pretty significant
amount of land with solar panels and wind turbines
and also building very big transit lines to bring all that electricity lines
to bring all that electricity from the countryside into the city.
Both of those things were often very strongly resisted by local communities,
as well as by conservation biologists
who were concerned about the impacts on wild bird species and other animals.
Now, there was a lot of other people
working on technical solutions at the time.
One of the big challenges, of course,
is just the intermittency of solar and wind
they only generate electricity about 10 to 30 percent of the time
during most of year.
but some of the solutions that were being proposed
were to convert hydroelectric dams into gigantic batteries.
the idea was that when the Sun
was shining and the wind was blowing you
would pump the water uphill store it for
later and then when you needed
electricity run it over the turbines in
terms of Wildlife some of these problems
just didn't seem like a significant
concern so when I learned that house
cats kill billions of birds every year
it put into perspective the hundreds of
thousands of birds rather that are
killed by wind turbines it basically
seemed to me at the time that most if
not all of the problems of scaling up
solar and wind could be solved through
more technological innovation but as the
years went by these problems persisted
and in many cases grew worse so
California is a state that's really
committed to renewable energy but we
still haven't converted many of our
hydroelectric dams into big batteries
some of the problems are just Geographic
it's just you have to have a very
particular kind of formation to be able
to do that and even in those cases it's
quite expensive to make those
conversions other challenges are just
that there's other uses for water like
irrigation and maybe this is the most
significant problem is just that in
California the water in our rivers and
reservoirs is growing increasingly
scarce and unreliable due to climate
change in terms of this issue of
reliability
as a consequence of it we've actually
had to stop the electricity coming from
the solar farms into the cities because
there's just been too much of it at
times or we've been starting to pay our
neighboring states like Arizona to take
that solar electricity the alternative
is to suffer from blowouts of the grid
and it turns out that
when it comes to birds and cats cats
don't kill Eagles Eagles kill cats what
cats kill are the small common sparrows
and Jay's and Robins birds that are not
endangered and not at risk of going
extinct what what do kill Eagles and
other big birds like this kite as well
as owls and condors and other threatened
and endangered species are wind turbines
in fact they're one of the most
significant threats to those big bird
species that we have we just haven't
been introducing the airspace with many
other objects like we have wind turbines
over the last several years and in terms
of solar you know building a solar farm
is a lot like building any other kind of
farm you have to clear the whole area of
Wildlife
so this is a picture of one third of one
of the biggest solar farms in California
called Ivanpah in order to build this
they had to clear the whole area of
desert tortoises literally pulling
desert tortoises and their babies out of
burrows putting them on the back of
pickup trucks and transporting them to
captivity where many of them ended up
dying and currently the current
estimates are that about 6,000 birds are
killed every year actually catching on
fire above the solar farm and plunging
to their deaths over time it gradually
struck me that there was really no
amount of technological innovation that
was gonna make the sunshine more
regularly or wind blow more reliably in
fact nothing could you could make solar
panels cheaper you could make wind
turbines bigger but sunlight and wind
are just really dilute fuels and in
order to produce significant amounts of
electricity
you just have to cover a very large land
mass with them in other words all of the
major problems with renewables aren't
technical they're natural well dealing
with all of this unreliability and the
big environmental impacts obviously
comes at a pretty high economic cost you
know we've been hearing a lot about how
solar panels and wind turbines have come
down in cost in recent years but that
cost has been significantly outweighed
by just the challenges of integrating
all of that unreliable power onto the
grid just take for instance what's
happening
or Nia at the period in which solar
panels have come down in price very
significantly same with wind we've seen
our electricity prices go up five times
more than the rest of the country and
it's not unique to us you can see the
same phenomenon happened in Germany
which is really the world's leader in
solar wind and other renewable
technologies their prices increased 50
percent during their big renewable
energy push now you might think well
dealing with climate change is just
going to require that we all pay more
for energy that's what I used to think
but consider the case of France France
actually gets twice as much of its
electricity from clean zero emission
sources than does Germany and yet France
pays half as much almost half as much
for its electricity how can that be well
you might have already anticipated the
answer France gets most of its
electricity from nuclear power
about 75% in total and nuclear just ends
up being a lot more reliable generating
power 24 hours a day seven days a week
for about 90% of the year we see this
phenomenon show up at a global level so
for example there's been a natural
experiment over the last 40 years even
more than that or in terms of the
deployment of nuclear and the deployment
of solar you can see that at a little
bit higher cost we got about half as
much electricity from solar and wind
than we did from nuclear well what does
all this mean for going forward I think
one of the most significant findings to
date is this one had Germany spent five
hundred eighty billion dollars on
nuclear instead of renewables it would
already be getting a hundred percent of
its end of its electricity from clean
energy sources and all of its
transportation energy now I think you
might be wondering and it's quite
reasonable to ask is nuclear power safe
and what do you do with the waste well
those are very reasonable questions
turns out that there's been scientific
studies on this going over 40 years this
is just the most recent study that was
done by the prestigious British Medical
Journal Lancet finds that nuclear power
is the safest it's easy to understand
why according to the World Health
Organization about 7 million people die
annually from air pollution and nuclear
plants don't emit that as a result the
climate scientist James Hansen looked at
and he calculated that nuclear power has
already saved almost two million lives
to date it turns out that even wind
energy is more deadly than nuclear this
is a photograph taken of two maintenance
workers in the Netherlands
shortly before one of them fell to his
death to avoid the fire and the other
one was engulfed in flames
now what about environmental impact well
I think a really easy way to think about
it is that uranium fuel which is what we
use to power nuclear plants is just
really energy dense about his mouth
about the same amount of uranium as this
is this Rubik's Cube can power all of
the energy that you need in your entire
life
as a consequence you just don't need
that much land in order to produce a
significant amount of electricity here
you can compare the solar farm I just
described Ivanpah to California's last
nuclear plant Diablo Canyon it takes 450
times more land to generate the same
amount of electricity as it does from
nuclear you would need 17 more solar
farms like Ivanpah in order to generate
the same output as Diablo Canyon and of
course it would then be unreliable well
what about the mining and the waste and
the material throughput well this has
been studied pretty closely as well and
it just turns out that solar panels
require 17 times more materials than
nuclear plants do in the form of cement
glass concrete steel and that includes
all the fuel used for those nuclear
plants the consequence is that what
comes out at the end since its material
throughput is just not a lot of waste
from nuclear all of the waste from the
Swiss nuclear program fits into this
room nuclear waste is actually the only
waste from electricity production
that's safely contained and internalized
every other way of making electricity
emits that waste into the natural
environment either as pollution or as
material waste we tend to think of solar
panels as clean but the truth is is that
there is no plan to deal with solar
panels at the end of their 20 or 25 year
life a lot of experts are actually very
concerned that solar panels are just
going to be shipped to poor countries in
Africa or Asia with the rest of our
electronic way
stream to be disassembled often exposing
people to really high levels of toxic of
toxic elements including lead cadmium
and chromium elements that because their
elements their toxicity never declines
over time I think we have an intuitive
sense that nuclear is a really powerful
strong energy source and that sunlight
is really dilute and diffuse and weak
which is why you have to spread solar
collectors or wind collectors over such
a large amount of land maybe that's why
nobody was surprised when in the recent
science-fiction remake of Blade Runner
the film opens a very dark dystopian
scene where California's deserts have
been entirely paved with solar farms all
of which I think raises a really
uncomfortable question in the effort to
try to save the climate are we
destroying the environment well the
interesting thing is that over the last
several hundred years human beings have
actually been trying to move away from
what you would consider matter dense
fuels towards energy dense ones that
means really from wood and dung towards
coal oil natural gas uranium this is a
phenomenon that's been going on for a
long time poor countries around the
world are in the process still of moving
away from wood and dung as their primary
energies and for the most part this is a
positive thing as you stop using wood as
your major source of fuel it allows the
forests to grow back and the wildlife to
return as you stop burning wood in your
home you don't you no longer need to
breathe that toxic smoke and as you go
from coal to natural gas and uranium is
your main sources of energy it holds out
the possibility of basically eliminating
air pollution altogether there's just
this problem with nuclear well it's been
pretty popular to move from dirtier to
cleaner energy sources from energy
diffuse to energy dense sources nuclear
is just really unpopular for a bunch of
historical reasons and as a consequence
in the past I and I think a lot of
others have sort of said well in order
to deal with climate change we're just
going to need all the different kinds of
clean energy that we have the problem is
is that just turns out not to be true
you remember I discussed France a little
bit ago France
gets most of its electricity from
nuclear if France were to try to
significantly scale up solar and wind it
would also have to significantly reduce
how much electricity it gets from
nuclear that's because in order to
handle the huge variability of solar and
wind on the grid they would need to burn
more natural gas think of it this way
it's just really hard to ramp up and
down a nuclear plant whereas I think
we're all pretty familiar with turning
the natural gas up and down on our stove
a similar process works in managing the
grid of course goes without saying that
oil and gas companies understand this
pretty well which is why we've seen them
invest millions of dollars in recent
years in promoting solar and wind this
just raises I think another challenging
question which is that in places that
are using a lot of nuclear have grids
that are mostly nuclear and hydro going
towards solar and wind and other
renewables would actually increase
carbon emissions I think a better
alternative is just to tell the truth
and that's what a number of scientists
have been doing I mentioned earlier that
hundreds of thousands of birds are
killed every year by wind turbines but I
didn't mention is that a million bats at
a minimum are killed every year by wind
the consequence has been that bad
scientists have been speaking out about
this this particular bat species the
hoary bat which is a migratory bat
species is literally at risk of going
extinct right now because of the
significant expansion of wind it's not
just wind it's also on solar the
scientists who were involved in creating
the Ivanpah solar farm who involved in
clearing that land have been speaking
out one of them wrote everybody knows
that translocation of desert tortoises
doesn't work when you're walking in
front of a bulldozer or crying and
moving animals and cacti out of the way
it's hard to think that the project is a
good idea and now we can see these
phenomena at work at an international
level in my home state of California
we've been stuffing a lot of natural gas
into the side of a mountain in order to
handle all that intermittent solar and
wind
it's sprung a leak it was equivalent to
putting 500,000 cars on the road and
currently in Germany there's protesters
trying to block a new coal mining
project
that would involve destroying the
ancient Han back forest in order to get
to the coal underneath all in an effort
to phase out nuclear and expand solar
and wind the good news is is that I
think that people still care about
nature enough for these facts to matter
we saw last year in South Korea a
citizen's jury deliberated for several
months weighing these different issues
they had to decide whether they were
going to phase out nuclear or keep it
and expanded they started out 40 percent
in favor of expanding nuclear but after
several months and considering these
issues they ended up voting 60 percent
to expand nuclear a similar phenomena
just happened last week in Arizona the
voters had a ballot initiative that to
vote on whether or not to continue with
nuclear or to phase it out and try to
replace it with natural gas and solar
they ended up rejecting at 70 to 30 and
even here in Europe we saw the
Netherlands is that one of the first
countries in recent memory to actually
announce as they did last week that
they're going to start to they're gonna
start to increase their reliance on
nuclear power in recognition that
there's just no way they could generate
significant amounts of energy enough
from solar and wind to meet their
climate targets I think it's natural
that those of us that became very
concerned about climate change such a
big environmental issue would gravitate
towards really romantic solutions like
harmonizing human civilization with the
natural world using renewable energies
but I think it's also understandable
that as the facts have come in that many
of us have started to question our prior
beliefs and change our minds for me the
question now is now that we know that
renewables can't save the planet are we
going to keep letting them destroy it
thank you very much