Translator: Katarina Ericson Reviewer: Denise RQ
Hello, good morning, it's a pleasure to be with you.
I thought of what should I talk about
when I had this incredible opportunity to stand in front of a crowd like this,
and I realized that the thing I should talk about is what powers us all:
how about talking about sunlight as we know it?
The reason why I thought this would be a good place to start
is because there are some amazing transformations
that are about to come upon us,
both in the form of global warming
and in the form of trying to figure out how to stop it.
As a way of maybe coming with a solution,
one thing you can imagine doing is say, "Well, what if?"
What if I can power the world with things it has been powered with all along,
which is sunshine.
What if we can take some of the sunlight and run the electricity
that spends about half of the energy we use to run the world as we know it?
What would that do?
By the way, if we ran our cars on electricity,
that would be another amazing thing to do.
But let me ask today,
how much of today's electricity is actually used from solar generation?
It's about one percent.
It doesn't sound like very much, not unless you put it in perspective.
The perspective is very simply this:
solar deployment as we know it has been growing about 40% a year,
year after year after year.
The last 15 years, go out and check the data,
every single one of the data points
will actually exceed any prediction we have ever made.
If you had asked us a few years back,
when will we have 200 gigawatts peak installed solar technology,
the answer would have been, "I don't know, in about 15 years from now."
Well, no, actually it's today.
And if you project, compound interest tells you that by year 2030,
155 % of the world's electricity will be provided by solar,
which is a bit too far of an extrapolation,
but it is growing.
Then the question becomes, what's next, and how do we actually embrace it,
because it is transformational, it is really disruptive,
and it is actually quite a challenge to absorb inside the system as we know it.
So let me tell you about the dominant solar technology,
and you might have seen, driving around towns here,
that roofs of Massachusetts homes do indeed have a lot of solar installed,
and typically in the form of what we call residential installations.
The other way you might find solar is driving around the fields next to roadways
you can find these large installations of what is called utility-installed solar.
These are incredible installations
from the perspective of providing us solar energy.
The question then becomes, "Well, alright, how are we doing?"
From the ability to actually replace coal
and gas-burning power plants with solar installations,
we had better meet the cost targets.
Are we doing our job?
Are we doing our job as scientists, technologists,
people who really want to come up and make a difference,
with what we are working on in labs.
And the answer is yes.
By the way,
the thing to note is there are two parts of solar you have to worry about:
there is a module, the thing you see on top of a home,
and then there's what we call a balance of systems,
all the wires you don't see,
and yet are fairly important for the final installation.
You know someone needs to mount that cell on your roof,
you need aluminium to frame it and hold it on the roof,
there had better be wires and something to connect it to the grid.
Hmm. All these things do cost extra money.
How much extra?
Well, that's what this batch plot shows.
The cost of the module, the actual cell that absorbs light,
we've worked so hard on it that since 2008 the cost went down about 85%.
An incredible drop.
But balance of systems,
we really haven't had a chance to work much on it.
Or maybe it's just that we cannot really do much better
than what we are already doing.
Is that maybe the real challenge?
Well, how do we figure this one out?
How come balance of systems costs twice as much, as it does?
I would say the reason is that solar cells weigh as much as they do.
And you say, "Well, that's kind of ridiculous."
Why would the weight matter for a solar cell? It does.
If I want to deploy it,
I must come up with something that's easy to either unroll or screw onto the roof,
or, indeed, other installation.
If I can change the weight of the cell,
maybe I can change the paradigm of what solar really, really means,
and how I would use it and think about installing it.
Let me show you some options, new options,
that we've been tossing around the lab for a decade or so,
thinking about what else beyond silicon, that's on the left of the graph.
Typically, silicon is made by a person who makes solar cells out of it,
and this is a very simple material
that generates a complex manufacturing process to give you the cell.
Can I switch that around?
There are many so-called nano-materials
that have been invented in the past decade or two,
molecules, quantum dots, polymers, a variety of these little things,
that can give us solar cells as well.
Except we never think of them as really useful materials
because they are very complex to make in a beaker.
And then, the next step is simply spraying them on,
and printing them with printers like this.
Well, how old is this printer?
It was finally developed last year.
And here it is, printing hundred molecule-thick layers,
in order to make a thin layer that may be used as a light-making device
or a solar cell, indeed.
Indeed this printer might revolutionize the way we think
about what it means to print a solar cell.
But wait, wait, I'm still printing on a piece of glass.
That won't solve my weight issue,
though it might give me a unique way of using different material sets.
Indeed, by printing, I can go from a wafer,
this is just a close-up view,
the wafer thickness compared to the hair thickness,
compared to the present commercial thin films,
compared to the new thin films that we imagine we should be able to do.
I'll show you some of these.
The key next advance
is the ability to make lightweight and integrated solar
that will be on any surface you touch without you even knowing it's there.
How would that look?
Let me show you one.
This is a piece of paper,
and my solar cell is made of organic dyes.
And you say, "What's that?"
Actually they are pigments, used to color blue and red cars.
Those can be used as semi-conductors, just like silicon can.
And here it is, one of those solar cells.
I'm going to go ahead and attach it to some electrodes,
shine some light on that piece of paper that has been painted,
and you can run a little electronic device with it.
You can now imagine having power on any surface you touch.
As a matter of fact, what would it be like if I actually use a true piece of paper;
let me feed it through a laser printer and see what happens.
In a lab, I would officially call it a stress test
in order to justify my research,
but, at the end of the day,
I just submitted this cell to a 300-celsius thermal cycle,
printed a label on top of it, it really shouldn't work any more,
but shine a light and it still does.
The way to think of solar now means that you can find it on any surface,
using new technology that could be roll to roll,
abundant material sets that are widely available,
lightweight and easy to deploy.
Here is another one; it is so light that it can sit on top of a soap bubble
because it weighs micrograms.
You don't even know it's there.
What would that imply?
It implies that any surface you touch,
newspapers, any surface you touch, would be able to be solar active,
and where would that matter?
It would actually matter a lot in places like this,
places that have no access to grid electricity
and hence rely on solar installations to power their villages.
How did the solar cells get to this village?
Well, this way.
And that person carrying the solar cell,
he or she doesn't care what the efficiency of the cell is.
The only thing they care about is,
"How many watts per kilogram am I carrying on my back?"
Give me a very lightweight cell
and I'll be able to outfit that village much more rapidly,
deliver it much more rapidly into it, with solar technologies.
What are other goofy ways you might see solar deployed?
How about this; this is a solar cell made of things called quantum dots,
really small chunks of stone that could be optically active;
absorb light, give electricity back,
and as a result you might find it in formats like this: sunglasses.
Why would you care about having sunglasses outfitted with a solar cell?
Maybe you never want to recharge your hearing aids,
because you would never have to,
because indeed they would repower right next to your ear.
Maybe your wireless earphone would have a way to be powered
using this particular technology.
If you're in a warm climate,
maybe you want a thermo-electric cooler behind your neck,
to cool you down?
There are options and options and look how cool they are,
I mean that's the other thing to look at.
(Laughter)
Now I'll show you a really cool one,
because some of you might say,
"Well, in a typical room, I don't want to wear my sunglasses."
But you might want to wear these solar cells,
also made of molecules.
Unique molecules that don't absorb any visible light.
"That's ridiculous, solar cells had better absorb light," you say.
I agree, hence why we designed cells that don't absorb any visible light,
but do absorb ultraviolet and infrared light.
So you can make a cell that looks as transparent as a piece of glass;
here it is.
That's an actual solar cell.
The way it works is that any time UV or IR light,
ultraviolet or infrared light,
hits this particular cell, it converts into electricity.
Visible just goes through.
So you can make devices like this.
This is a little e-reader,
electronic reader that's been covered with one of these solar cells,
and what we are doing is covering the e-reader with a notebook,
and then uncovering it.
On the right side is the voltmeter
that tells you how many volts you are generating;
any time you uncover it, ten volts come out,
when you cover it the voltage goes down to zero,
because no room light or sunlight is hitting your e-reader.
But let me show you exactly what you have been looking through,
so you get a sense of how transparent this is.
That's your solar cell.
That's your solar cell that can now be deployed on any surface,
without you knowing that it's even there.
That's a solar cell that can now indeed be integrated with your regular glasses,
if that's what you want to do.
This e-reader, you would never have to recharge it again, ever,
because in a matter of just a few days of room light,
half an hour of sunlight,
you will be able to recharge this battery fully.
And a battery typically lasts a couple of weeks.
How would you relate to your electronics if you never had to recharge again?
How would you relate to your power
if you never have to worry if it will be there or not?
Because any surface you touch would have a micron-thick film
that would absorb the light
and give you electricity back as you need it.
Start with something small like this, because I should warn you;
everything I've show you today is new,
and any hardware technology
takes about a decade to go from basic invention to impact,
where a million people can hold it in their hand.
Is it as simple as a zipper or Velcro,
that took about 12 or 13 years,
or more complex, like organic leds, that took about 20 years,
to go and commercialize from the basic idea to impact.
As a result, it takes a little while, but one day, this will be the goal.
Come up with a way to outfit every surface we touch
and every surface we look through,
to provide ubiquitous access to power,
as we need it.
Thank you.
(Applause)