Hi, I'm Steve Chu, and I am back at
Stanford University having spent four
and a quarter year's sabbatical as
US Secretary of Energy.
I'm here to talk about some renewable technologies that
can actually give us clean
sustainable energy and it's going to mitigate
the changes in climate change.
Where are we today? Well, wind has made
dramatic progress in the last 30-plus
years from 1980 till today.
We see the cost of wind plummeting.
And now long-term contracts are being signed
today which are agreeing to sell wind
electrical energy at two-and-a-half to
three cents a kilowatt hour to two
leading companies. If you compare that to
new natural gas or coal,
if you build a new natural gas plant today and assume
that natural gas over the lifetime of
the plant is four dollars million btu,
which is historically very very low,
you'll find that natural gas without
wind subsidy is comparable.
Wind is already cheaper than a new coal plant
What about solar energy?
This is what's called a learning curve as you go and
you ship more and more solar modules out,
the price gets lower and lower due to a
series of ten technological innovations.
This slide was made 2008 where they
showed where the price of solar modules
was at that time. With a prediction by
2015, it's beginning to approach
wholesale cost of electricity,
estimated perhaps to be fifteen ten cents a
kilowatt hour; that projection was
incorrect.
What we see is that we have already by
2015 actually reached grid parity?
How do I know this?
Look again at the contracts being signed.
In 2008, the contracts being
signed were pricing solar at eighteen
twenty cents a kilowatt hour; four years later,
2014, contracts being signed in
Texas pricing solar at five cents and
4.8 cents kilowatt-hour - grid parity, amazing.
And so solar energy is going to become
lower and lower as well as wind. So as I
came into the apartment energy, we said
those are technologies they're well on their path,
we will continue to fund
research in them because they're going
to get better, but we are also seeking
other disruptive technologies, and by that,
let me tell you about, first, existing
technology going into the 20th century.
That existing technology was a
horse-and-buggy; there were innovations
a steam-powered car actually introduced
before in the seventeen hundreds -
didn't work. That, well, never took on.
By the mid late eighteen hundreds,
the Benz Motorwagen, using a diesel internal
combustion engine,
it was a great car, but it wasn't disruptive
because it costs too much.
The disruptive technology was
technologically good and it met the price,
and it was the actual Ford model T
affordable by a large fraction of
Americans that actually began to replace
the horse and buggy is another example.
We call this a transformational
technology and so the Tesla is a
wonderful great car; it costs a hundred
thousand dollars. It will not be a mass marketed car.
We need something like a
Tesla that costs 20 - 25 thousand dollars
And that's what we're looking for,
and to that end we're doing research on batteries.
For example, the Tesla battery
has about 250 watt hours per kilogram.
It weighs 1,200 pounds and
costs thirty thousand dollars.
That's a lot of money, but there's a lot of weight.
And we need a battery that has
five times higher energy density so
it weighs two or three hundred pounds,
and then it has 10 times faster charging rate,
and my motto was we need a battery that could
be charged faster and could last longer
than the bladder.
That means no one really drives 400
miles in one sitting, or very few people do.
They will stop after 200 miles if they
can charge their car to go another 200
miles in five minutes,
that's good enough. What we have today
are batteries with this energy density
that weighs 1,200 pounds.
The next generation batteries being investigated
by a number of companies are with a
silicon anode; they could maybe double
the capacity, and the third generation
would combine lithium with sulfur,
which could again double it,
so then we could have a battery instead
of weighing 1,200 pounds could weigh a
couple hundred pounds 200 pounds -
same weight as an internal combustion engine
and transmission, and it could charge -
we need a battery that can charge 10 times faster,
so that would be very exciting.
Another thing we began to think about at
the Department of Energy is as you see
the technology developing,
are you prepared for the next thing, that is,
for inexpensive renewable energy,
and instead of being passive about this,
we began to actively examine what happens as the
technology gets better and better.
Would it be self-limiting? And let me give you an example.
As we transition from
ten or fifteen percent renewable energy,
which is where we are today,
ten percent to fifty percent, you actually need a much
more flexible transmission and
distribution model. I should also point
out when you're fifty percent
intermittent renewable energy,
you need backup power so the cost of renewable
energy actually has to include that back up power,
which is standby just in case
the wind doesn't blow, the Sun doesn't shine.
Therefore, renewable energy has to
get actually significantly less
expensive than new natural gas;
it is already significantly less expensive than coal,
but it's going to happen.
10 and certainly 20 years from today,
it will happen, so what else do we need.
We need long distance transmission.
We begin to need energy storage but the good news
is
when we have fifty percent intermittent
energy, there are days where you'll have
lots of surplus energy and indeed at
night you can buy electricity for
example in California at one-quarter of
the usual rate by electricity.
Each sells from somewhere between a half a
cent two cents a kilowatt hour, and two
decades from today, I am confident
that we will be generating renewable
energy at two cents a kilowatt hour or less,
so we have very inexpensive electricity,
we can power and replace a
lot of fossil fuel, but what else do we need.
We need, and this is a challenge,
we need a new technology.
We need to be able to take water and split it into
hydrogen and oxygen, and then we need to
capture carbon dioxide very inexpensively.
Again, we don't have the
technology today but there are a number
of laboratories and number of companies
that are developing trying to develop
technology that will be four times less expensive.
At their target price and the
splitting of water into hydrogen,
you then have the ingredients for a real
sustainable energy; that is to say you take water,
you recycle carbon dioxide,
and what do you do? You take the water,
you split it into hydrogen and oxygen,
you take the carbon capture carbon dioxide,
you have it undergo catalytic
transformation to build linear
hydrocarbon chains.
These hydrocarbon chains are the molecules we use in jet fuel
and diesel fuel and gasoline.
A long-distance transmission line is an oil tanker.
We know that oil ships around
the world for a couple bucks a barrel,
and so if we had this technology and
the very inexpensive electricity,
the energy problem would be well on the way to
getting to choose sustainability.
As I went to Washington, I confronted a
embedded established economy.
It's sort of like the horse and buggy whip lobby
really trying to tell Congress not to
support the development of water mobiles,
that they were dangerous,
and they would disrupt the American Way of life.
Similarly, there is this issue with the
embedded fossil fuel companies,
but as a scientist in Washington, it was my duty
my mission, to dispassionately and calmly
try to inform people in Congress as well
as others in government that this is necessary,
is going to take decades,
we've got to do this, but it will ultimately
be the low cost option,
so let me conclude of a picture, one of my favorites,
taken Christmas Eve 1968.
It was an Apollo 8, the first mission that
orbited the moon, and the last orbit the
astronauts turn the capsule earthward,
and they one of the astronauts took this picture,
which he called Earthrise,
and Bill Anders the astronaut who took the pictures
said we came all this way to explore the
moon, and the most important thing is we
discovered the earth. Now if you look at
that picture it doesn't take too much
imagination to realize the moon is not a
good place to live. From this vantage point,
Earth looks very inviting,
and guess what, there's nowhere else to go.
Since nineteen sixty-eight,
we've discovered that the climate is changing.
There is very compelling evidence that a
large part of it is due to humans,
and we have to get into a better position
because really we have to take care of
the Earth because of us and our people
and our grandchildren and there's
nowhere else to go, and so that's why I
went to Washington.
Thank you
