WEBVTT

00:00:01.994 --> 00:00:04.761
You may have noticed
that I'm wearing two different shoes.

00:00:06.776 --> 00:00:08.518
It probably looks funny --

00:00:08.518 --> 00:00:10.192
it definitely feels funny --

00:00:10.192 --> 00:00:11.872
but I wanted to make a point.

00:00:12.698 --> 00:00:16.964
Let's say my left shoe corresponds
to a sustainable footprint,

00:00:16.964 --> 00:00:20.254
meaning we humans consume
less natural resources

00:00:20.254 --> 00:00:22.501
than our planet can regenerate,

00:00:22.501 --> 00:00:27.013
and emit less carbon dioxide
than our forests and ocean can reabsorb.

00:00:27.532 --> 00:00:29.568
That's a stable and healthy condition.

00:00:30.486 --> 00:00:33.487
Today's situation
is more [like] my other shoe.

00:00:33.777 --> 00:00:35.324
It's way oversized.

00:00:36.070 --> 00:00:39.309
At the second of August in 2017,

00:00:39.309 --> 00:00:41.574
we have already consumed all resources

00:00:41.574 --> 00:00:43.664
our planet can regenerate this year.

00:00:44.844 --> 00:00:48.355
This is like spending all your money
until the [eighteenth] of a month,

00:00:48.355 --> 00:00:51.477
and then needing a credit
from the bank for the rest of the time.

00:00:51.656 --> 00:00:53.992
For sure you can do this
for some months in a row,

00:00:53.992 --> 00:00:55.939
but if you don't change your behavior,

00:00:55.939 --> 00:00:58.436
sooner or later you will
run into big problems.

00:00:59.291 --> 00:01:03.936
We all know the devastating effects
of this excessive exploitation:

00:01:03.936 --> 00:01:05.409
global warming,

00:01:05.409 --> 00:01:07.216
rising of the sea levels,

00:01:07.216 --> 00:01:09.546
melting of the glaciers and polar ice,

00:01:09.546 --> 00:01:12.117
increasingly extreme climate patterns

00:01:12.117 --> 00:01:13.118
and more.

00:01:14.528 --> 00:01:17.190
The enormity of this problem
really frustrates me.

00:01:18.418 --> 00:01:21.761
What frustrates me even more
is that there are solutions to this,

00:01:21.761 --> 00:01:24.114
but we keep doing things
like we always did.

00:01:24.599 --> 00:01:26.477
Today I want to share with you

00:01:26.477 --> 00:01:29.263
how a new solar technology can contribute

00:01:29.263 --> 00:01:31.311
to a sustainable future of buildings.

00:01:32.624 --> 00:01:36.785
Buildings consume about 40 percent
of our total energy demand,

00:01:36.785 --> 00:01:38.256
so tackling this consumption

00:01:38.256 --> 00:01:40.846
would significantly reduce
our climate emissions.

00:01:41.476 --> 00:01:43.818
A building designed
along sustainable principle

00:01:43.818 --> 00:01:46.202
can produce all the power
it needs by itself.

00:01:46.868 --> 00:01:47.909
To achieve this,

00:01:47.909 --> 00:01:51.509
you first have to reduce
the consumption as much as possible

00:01:51.509 --> 00:01:54.402
by using well-insulated walls
or windows for instance.

00:01:54.773 --> 00:01:56.971
These technologies
are commercially available.

00:01:57.845 --> 00:02:00.483
Then you need energy
for warm water and heating.

00:02:01.130 --> 00:02:03.994
You can get this in a renewable
way from the sun

00:02:03.994 --> 00:02:05.728
through solar thermal installations

00:02:05.728 --> 00:02:07.869
or from the ground and air
with heat pumps.

00:02:08.023 --> 00:02:09.983
All of these technologies are available.

00:02:11.020 --> 00:02:13.371
Then you are left
with the need for electricity.

00:02:14.001 --> 00:02:14.997
In principle,

00:02:14.997 --> 00:02:17.916
there are several ways
to get renewable electricity,

00:02:17.916 --> 00:02:19.560
but how many buildings do you know

00:02:19.560 --> 00:02:21.199
which have a windmill on the roof,

00:02:21.199 --> 00:02:23.162
or a water power plant in the garden?

00:02:23.578 --> 00:02:26.391
Probably not so many because
usually it doesn't make sense.

00:02:26.653 --> 00:02:30.150
But the sun provides abundant
energy to our roofs and façades.

00:02:31.390 --> 00:02:35.840
The potential to harvest this energy
at our buildings' surfaces is enormous.

00:02:36.763 --> 00:02:38.566
Let's take Europe as an example.

00:02:39.206 --> 00:02:43.641
If you would utilize all areas
which have a nice orientation to the sun

00:02:43.641 --> 00:02:45.347
and they're not overly shaded,

00:02:45.347 --> 00:02:48.378
the power generated
by photovoltaics

00:02:48.378 --> 00:02:51.843
would correspond to about 30 percent
of our total energy demand.

00:02:52.303 --> 00:02:54.871
But today's photovoltaics
have some issues.

00:02:55.746 --> 00:02:58.276
They do offer a good
cost-performance ratio,

00:02:58.276 --> 00:03:00.966
but they aren't really flexible
in terms of their design,

00:03:00.966 --> 00:03:02.789
and this makes aesthetics a challenge.

00:03:03.235 --> 00:03:05.710
People often imagine pictures like this

00:03:05.710 --> 00:03:07.907
when thinking about
solar cells on buildings.

00:03:08.120 --> 00:03:09.986
This may work for solar farms,

00:03:09.986 --> 00:03:11.539
but when you think of buildings,

00:03:11.539 --> 00:03:12.542
of streets,

00:03:12.542 --> 00:03:13.572
of architecture,

00:03:13.572 --> 00:03:14.994
aesthetics does matter.

00:03:15.520 --> 00:03:19.067
This is the reason why we don't see
many solar cells on buildings today.

00:03:19.567 --> 00:03:20.892
They just don't match.

00:03:21.861 --> 00:03:25.394
Our team is working on a totally
different solar cell technology.

00:03:26.177 --> 00:03:28.461
It's just called organic photovoltaics,

00:03:28.461 --> 00:03:29.458
or OPV.

00:03:29.730 --> 00:03:31.480
The term organic describes

00:03:31.480 --> 00:03:33.995
that the material used
for light absorption

00:03:33.995 --> 00:03:35.414
and charge transport

00:03:35.414 --> 00:03:37.531
are mainly based on the element carbon,

00:03:37.531 --> 00:03:38.726
and not on metals.

00:03:39.339 --> 00:03:42.185
We utilize the mixture of a polymer

00:03:42.185 --> 00:03:44.811
which is set up by different
repeating units,

00:03:44.811 --> 00:03:46.864
like the pearls in a pearl chain,

00:03:46.864 --> 00:03:49.786
and a small molecule
which has the shape of a football

00:03:49.786 --> 00:03:51.131
and is called fullerene.

00:03:51.906 --> 00:03:55.837
These two compounds are mixed
and dissolved to become an ink.

00:03:56.437 --> 00:03:57.487
And like ink,

00:03:57.487 --> 00:04:02.190
they can be printed with simple
printing techniques like slot-die coating

00:04:02.190 --> 00:04:06.041
in a continuous roll-to-roll process
on flexible substrates.

00:04:06.855 --> 00:04:08.244
The resulting thin layer

00:04:08.244 --> 00:04:11.077
is the active layer absorbing
the energy of the sun.

00:04:12.167 --> 00:04:14.578
This active layer is extremely effective.

00:04:15.692 --> 00:04:19.205
You only need a layer thickness
of 0.2 micrometers

00:04:19.205 --> 00:04:20.837
to absorb the energy of the sun.

00:04:21.309 --> 00:04:23.777
This is 100 times thinner
than a human hair.

00:04:25.076 --> 00:04:27.053
To give you another example,

00:04:27.053 --> 00:04:29.733
take one kilogram of the basic polymer

00:04:29.733 --> 00:04:31.944
and use it to formulate the active ink.

00:04:32.780 --> 00:04:34.152
With this amount of ink,

00:04:34.152 --> 00:04:38.008
you can print a solar cell
the size of a complete football field.

00:04:39.342 --> 00:04:43.075
So OPV is extremely material efficient,

00:04:43.075 --> 00:04:46.175
which I think is a crucial thing
when talking about sustainability.

00:04:47.534 --> 00:04:49.485
After the printing process,

00:04:49.485 --> 00:04:50.778
you can have a solar module

00:04:50.778 --> 00:04:53.265
which can look like this ...

00:04:53.265 --> 00:04:55.288
it looks a bit like a plastic foil,

00:04:55.288 --> 00:04:56.908
and actually has many of its features.

00:04:57.876 --> 00:05:00.679
It's lightweight ...

00:05:00.679 --> 00:05:02.712
it's bendable ...

00:05:02.712 --> 00:05:04.535
and it's semi-transparent.

00:05:07.201 --> 00:05:09.604
But it can harvest [the] energy
of the sun outdoors

00:05:09.604 --> 00:05:11.052
and also of this indoor light,

00:05:11.052 --> 00:05:13.818
as you can see with this small,
illuminated LED.

00:05:15.095 --> 00:05:17.043
You can use it in its plastic form

00:05:17.043 --> 00:05:19.929
and take advantage of its low weight
and it's bendability.

00:05:21.161 --> 00:05:24.480
The first is important when thinking
about buildings in warmer regions.

00:05:25.485 --> 00:05:28.622
Here, the roofs are not designed
to bear additionally heavy loads.

00:05:29.201 --> 00:05:31.837
They aren't designed for snow
in winter for instance,

00:05:31.837 --> 00:05:36.048
so heavy silicon solar cells
cannot be used for light harvesting,

00:05:36.048 --> 00:05:38.897
but these lightweight solar foils
are very well suited.

00:05:40.299 --> 00:05:42.746
The bendability is important

00:05:42.746 --> 00:05:46.203
if you want to combine the solar cell
with membrane architecture.

00:05:46.982 --> 00:05:50.463
Imagine the cells of the Sydney
Opera as power plants.

00:05:51.082 --> 00:05:53.513
Alternatively, you can
combine the solar foils

00:05:53.513 --> 00:05:55.944
with conventional construction
materials like glass.

00:05:56.604 --> 00:05:59.008
Many glass [façade] elements
contain a [foil] anyways

00:05:59.008 --> 00:06:00.821
to create laminated safety glass.

00:06:01.388 --> 00:06:04.865
It's not a big deal to add
a second foil in the production process,

00:06:04.865 --> 00:06:07.730
but then the façade element
contains the solar cell

00:06:07.730 --> 00:06:09.572
and can produce electricity.

00:06:11.265 --> 00:06:12.783
Besides looking nice,

00:06:12.783 --> 00:06:16.910
these integrated solar cells come along
with two more important benefits.

00:06:17.738 --> 00:06:20.962
Do you remember the solar cells
attached the roof I showed before?

00:06:21.561 --> 00:06:22.727
In this case,

00:06:22.727 --> 00:06:24.221
we install the roof first

00:06:24.221 --> 00:06:25.121
and as a second layer,

00:06:25.121 --> 00:06:26.163
the solar cell.

00:06:26.336 --> 00:06:28.834
This is adding on [the] installation cost.

00:06:29.058 --> 00:06:30.828
In the case of integrated solar cells,

00:06:30.828 --> 00:06:32.351
at the site of construction,

00:06:32.351 --> 00:06:34.320
only one element is installed,

00:06:34.320 --> 00:06:36.922
being at the same time
the envelope of the building

00:06:36.922 --> 00:06:37.929
and the solar cell.

00:06:38.965 --> 00:06:40.773
Besides saving on your installation costs,

00:06:40.773 --> 00:06:42.908
this also saves resources

00:06:42.908 --> 00:06:45.986
because the two functions
are combined into one element.

00:06:46.533 --> 00:06:48.388
Earlier I talked about optics.

00:06:48.590 --> 00:06:50.636
I really like this solar pattern,

00:06:50.636 --> 00:06:53.287
maybe you have different taste
or different design needs.

00:06:54.286 --> 00:06:55.344
No problem.

00:06:55.505 --> 00:06:56.841
With the printing process,

00:06:56.841 --> 00:07:00.986
the solar cell can change
its shape and design very easily.

00:07:01.774 --> 00:07:04.252
This will give the flexibility
to architects,

00:07:04.252 --> 00:07:06.271
to planners and building owners

00:07:06.271 --> 00:07:09.754
to integrate this electricty-producing
technology as they wish.

00:07:15.563 --> 00:07:18.289
I want to stress that this is not
just happening in the labs.

00:07:18.861 --> 00:07:21.532
It will take seven more years
to get to mass adoption,

00:07:21.532 --> 00:07:24.787
but we are at the edge
of commercialization,

00:07:24.787 --> 00:07:28.005
meaning there are several companies
out there with production lines.

00:07:28.795 --> 00:07:30.638
They are scaling up their capacities

00:07:30.638 --> 00:07:32.555
and so are we with the inks.

00:07:41.147 --> 00:07:43.472
This smaller footprint
is much more comfortable.

00:07:44.112 --> 00:07:45.241
(Laughter)

00:07:45.470 --> 00:07:46.675
It is the right size,

00:07:46.675 --> 00:07:47.773
the right scale.

00:07:48.202 --> 00:07:52.038
We have to come back to the right scale
when it comes to energy consumption.

00:07:52.714 --> 00:07:55.667
And making buildings carbon neutral
is an important part here.

00:07:56.510 --> 00:07:57.257
In Europe,

00:07:57.257 --> 00:08:00.875
we have the goal to decarbonize
our buildings [stock] until 2050.

00:08:01.374 --> 00:08:04.386
I hope organic photovoltaics
will be a big part of this.

00:08:05.452 --> 00:08:07.368
Here are a couple of examples.

00:08:08.291 --> 00:08:12.658
This is the first commercial installation
of fully printed organic solar cells.

00:08:13.481 --> 00:08:16.826
Commercial means that the solar cells
were printed on industrial equipment.

00:08:18.138 --> 00:08:21.508
The so-called solar trees are part
of the German pavilion

00:08:21.508 --> 00:08:24.138
at the World Expo in Milan in 2015.

00:08:24.788 --> 00:08:26.950
They provided shading during the day

00:08:26.950 --> 00:08:29.391
and electricity for
the lighting in evening.

00:08:29.920 --> 00:08:33.276
You may wonder why this hexagonal shape
was chosen for the solar cells.

00:08:33.884 --> 00:08:35.190
Easy answer:

00:08:35.190 --> 00:08:38.558
the architects wanted to have
a specific shading pattern on the floor

00:08:38.558 --> 00:08:39.847
and asked for it,

00:08:39.847 --> 00:08:41.774
and then it was printed as requested.

00:08:42.458 --> 00:08:44.151
Being far from a real project,

00:08:44.151 --> 00:08:47.974
this free-form installation hooked
the imagination of the visiting architects

00:08:47.974 --> 00:08:49.477
much more than we expected.

00:08:50.092 --> 00:08:52.577
This other application
is closer to the projects

00:08:52.577 --> 00:08:54.810
and applications we are targeting.

00:08:55.260 --> 00:08:58.038
In an office building
in Sao Paulo, Brazil,

00:08:58.038 --> 00:09:01.836
semi-transparent OPV panels
are integrated into the glass façade,

00:09:01.836 --> 00:09:02.909
serving different needs.

00:09:03.650 --> 00:09:06.688
First, they provided shading
for the meeting rooms behind.

00:09:07.746 --> 00:09:12.346
Second, the logo of the company
is displayed in an innovative way.

00:09:12.888 --> 00:09:14.627
And of course electricity is produced,

00:09:14.627 --> 00:09:16.760
reducing the energy footprint
of the building.

99:59:59.999 --> 99:59:59.999
This is pointing towards a future

99:59:59.999 --> 99:59:59.999
where buildings are no longer
energy consumers,

99:59:59.999 --> 99:59:59.999
but energy providers.

99:59:59.999 --> 99:59:59.999
I want to see solar cells
seamlessly integrated

99:59:59.999 --> 99:59:59.999
into our building shells

99:59:59.999 --> 99:59:59.999
to be both resource-efficient
and a pleasure to look at.

99:59:59.999 --> 99:59:59.999
For roofs, silicon solar cells
will often continue to be a good solution,

99:59:59.999 --> 99:59:59.999
but to exploit the potential
of all façades in other areas,

99:59:59.999 --> 99:59:59.999
such as sem-transparent areas,

99:59:59.999 --> 99:59:59.999
curved surfaces

99:59:59.999 --> 99:59:59.999
and shadings,

99:59:59.999 --> 99:59:59.999
I believe organic photovoltaics
can offer a significant contribution

99:59:59.999 --> 99:59:59.999
and they can be made in any form
architects and planners will want them to.

99:59:59.999 --> 99:59:59.999
Thank you.

99:59:59.999 --> 99:59:59.999
(Applause)