1 99:59:59,999 --> 99:59:59,999 You may have noticed that I'm wearing two different shoes. 2 99:59:59,999 --> 99:59:59,999 It probably looks funny -- 3 99:59:59,999 --> 99:59:59,999 it definitely feels funny 4 99:59:59,999 --> 99:59:59,999 but I wanted to make a point. 5 99:59:59,999 --> 99:59:59,999 Let's say my left shoe corresponds to [a] sustainable footprint, 6 99:59:59,999 --> 99:59:59,999 meaning we humans consume less natural resources 7 99:59:59,999 --> 99:59:59,999 than our planet can regenerate, 8 99:59:59,999 --> 99:59:59,999 and emit less carbon dioxide than our forests and ocean can reabsorb. 9 99:59:59,999 --> 99:59:59,999 That's a stable and healthy condition. 10 99:59:59,999 --> 99:59:59,999 Today's situation is more [like] my other shoe. 11 99:59:59,999 --> 99:59:59,999 It's way oversized. 12 99:59:59,999 --> 99:59:59,999 On the second of August in 2017, 13 99:59:59,999 --> 99:59:59,999 we have already consumed all resources our planet can regenerate 14 99:59:59,999 --> 99:59:59,999 this year. 15 99:59:59,999 --> 99:59:59,999 This is like spending all your money until the eighteenth of a month, 16 99:59:59,999 --> 99:59:59,999 and then needing a credit from the bank for the rest of the time. 17 99:59:59,999 --> 99:59:59,999 For sure you can do this for some months in a row, 18 99:59:59,999 --> 99:59:59,999 but if you don't change your behavior, 19 99:59:59,999 --> 99:59:59,999 soon or later you will run into big problems. 20 99:59:59,999 --> 99:59:59,999 We all know the devastating effects of this excessive exploitation. 21 99:59:59,999 --> 99:59:59,999 Global warming, 22 99:59:59,999 --> 99:59:59,999 rising of the sea levels, 23 99:59:59,999 --> 99:59:59,999 melting of the glaciers and polar ice, 24 99:59:59,999 --> 99:59:59,999 increasingly extreme climate patterns 25 99:59:59,999 --> 99:59:59,999 and more. 26 99:59:59,999 --> 99:59:59,999 The enormity of this problem really frustrates me. 27 99:59:59,999 --> 99:59:59,999 What frustrates me even more is that there are solutions to this, 28 99:59:59,999 --> 99:59:59,999 but we keep doing things like we always did. 29 99:59:59,999 --> 99:59:59,999 Today I want to share with you 30 99:59:59,999 --> 99:59:59,999 how a new solar technology can contribute 31 99:59:59,999 --> 99:59:59,999 to [the] sustainable future of buildings. 32 99:59:59,999 --> 99:59:59,999 Buildings consume about 40 percent of our total energy demand, 33 99:59:59,999 --> 99:59:59,999 so tackling this consumption would reduce our climate emissions. 34 99:59:59,999 --> 99:59:59,999 A building designed along sustainable principles 35 99:59:59,999 --> 99:59:59,999 can produce all the power it needs by itself. 36 99:59:59,999 --> 99:59:59,999 To achieve this you first have to reduce the consumption as much as possible 37 99:59:59,999 --> 99:59:59,999 by using well-insulated walls or windows for instance. 38 99:59:59,999 --> 99:59:59,999 These technologies are commercially available. 39 99:59:59,999 --> 99:59:59,999 Then you need energy for warm water and heating. 40 99:59:59,999 --> 99:59:59,999 You can get this in a renewable way from the sun, 41 99:59:59,999 --> 99:59:59,999 through solar thermal installations 42 99:59:59,999 --> 99:59:59,999 or from the ground and air with heat pumps. 43 99:59:59,999 --> 99:59:59,999 All of these technologies are available. 44 99:59:59,999 --> 99:59:59,999 Then you are left with the need for electricity. 45 99:59:59,999 --> 99:59:59,999 In principle, 46 99:59:59,999 --> 99:59:59,999 there are several ways to get renewable electricity, 47 99:59:59,999 --> 99:59:59,999 but how many buildings do you know 48 99:59:59,999 --> 99:59:59,999 which have a windmill on the roof, 49 99:59:59,999 --> 99:59:59,999 or a water power plant in the garden? 50 99:59:59,999 --> 99:59:59,999 Probably not so many 51 99:59:59,999 --> 99:59:59,999 because usually it doesn't make sense. 52 99:59:59,999 --> 99:59:59,999 But the sun provides abundant energy to our roofs and façades. 53 99:59:59,999 --> 99:59:59,999 The potential to harvest this energy on our building's surface is enormous. 54 99:59:59,999 --> 99:59:59,999 Let's take Europe as an example. 55 99:59:59,999 --> 99:59:59,999 If you would utilize all areas which have a nice orientation to the sun 56 99:59:59,999 --> 99:59:59,999 and they're not overly shaded, 57 99:59:59,999 --> 99:59:59,999 the power generated by photovoltaics 58 99:59:59,999 --> 99:59:59,999 would correspond to about 30 percent of our total energy demand, 59 99:59:59,999 --> 99:59:59,999 but today's photovoltaics have some issues. 60 99:59:59,999 --> 99:59:59,999 They do offer a good cost-performance ratio, 61 99:59:59,999 --> 99:59:59,999 but they aren't really flexible in terms of their design 62 99:59:59,999 --> 99:59:59,999 and this makes aesthetics a challenge. 63 99:59:59,999 --> 99:59:59,999 People often imaging pictures like this 64 99:59:59,999 --> 99:59:59,999 when thinking about solar cells on buildings. 65 99:59:59,999 --> 99:59:59,999 This may work for solar farms, 66 99:59:59,999 --> 99:59:59,999 but when you think of buildings, 67 99:59:59,999 --> 99:59:59,999 of streets, 68 99:59:59,999 --> 99:59:59,999 of architecture, 69 99:59:59,999 --> 99:59:59,999 aesthetics does matter. 70 99:59:59,999 --> 99:59:59,999 This is the reason why we don't see many solar cells on buildings today. 71 99:59:59,999 --> 99:59:59,999 They just don't match. 72 99:59:59,999 --> 99:59:59,999 Our team is working on a totally different solar cell technology. 73 99:59:59,999 --> 99:59:59,999 It's just called organic photovoltaics, 74 99:59:59,999 --> 99:59:59,999 or OPV. 75 99:59:59,999 --> 99:59:59,999 The term organic describes 76 99:59:59,999 --> 99:59:59,999 that the material used for light absorption 77 99:59:59,999 --> 99:59:59,999 and charge transport 78 99:59:59,999 --> 99:59:59,999 are mainly based on the element carbon, 79 99:59:59,999 --> 99:59:59,999 and not on metals. 80 99:59:59,999 --> 99:59:59,999 We utilize the mixture of a polymer, 81 99:59:59,999 --> 99:59:59,999 which is set up by different repeating units, 82 99:59:59,999 --> 99:59:59,999 like the pearls in a pearl chain, 83 99:59:59,999 --> 99:59:59,999 and a small molecule which has the shape of a football 84 99:59:59,999 --> 99:59:59,999 and is called fullerene. 85 99:59:59,999 --> 99:59:59,999 These two compounds are mixed and dissolved to become an ink, 86 99:59:59,999 --> 99:59:59,999 and like ink, 87 99:59:59,999 --> 99:59:59,999 they can be printed with simple printing techniques 88 99:59:59,999 --> 99:59:59,999 like slot-die coating 89 99:59:59,999 --> 99:59:59,999 in a continuous roll-to-roll process on flexible substrates. 90 99:59:59,999 --> 99:59:59,999 The resulting thin later 91 99:59:59,999 --> 99:59:59,999 is the active layer absorbing the energy of the sun. 92 99:59:59,999 --> 99:59:59,999 This active layer is extremely effective. 93 99:59:59,999 --> 99:59:59,999 You only need a layer thickness of 0.2 micrometers 94 99:59:59,999 --> 99:59:59,999 to absorb the energy of the sun. 95 99:59:59,999 --> 99:59:59,999 This is 100 times thinner than a human hair. 96 99:59:59,999 --> 99:59:59,999 To give you another example, 97 99:59:59,999 --> 99:59:59,999 take one kilogram of the basic polymer 98 99:59:59,999 --> 99:59:59,999 and use it to formulate the active ink. 99 99:59:59,999 --> 99:59:59,999 With this amount of ink, 100 99:59:59,999 --> 99:59:59,999 you can print a solar cell the size of a complete football field. 101 99:59:59,999 --> 99:59:59,999 So OPV is extremely material efficient, 102 99:59:59,999 --> 99:59:59,999 which I think is a crucial thing when talking about sustainability. 103 99:59:59,999 --> 99:59:59,999 After the printing process, 104 99:59:59,999 --> 99:59:59,999 you can have a solar module 105 99:59:59,999 --> 99:59:59,999 which can look like this ... 106 99:59:59,999 --> 99:59:59,999 it looks a bit like a plastic foil, 107 99:59:59,999 --> 99:59:59,999 and actually has many of its features. 108 99:59:59,999 --> 99:59:59,999 It's lightweight ... 109 99:59:59,999 --> 99:59:59,999 it's bendable ... 110 99:59:59,999 --> 99:59:59,999 and it's semi-transparent. 111 99:59:59,999 --> 99:59:59,999 But it can harvest [the] energy of the sun outdoors 112 99:59:59,999 --> 99:59:59,999 and also of this indoor light, 113 99:59:59,999 --> 99:59:59,999 as you can see with this small, illuminated LED. 114 99:59:59,999 --> 99:59:59,999 You can use it in its plastic form 115 99:59:59,999 --> 99:59:59,999 and take advantage of its low weight and it's bendability. 116 99:59:59,999 --> 99:59:59,999 The first is important when thinking about buildings in warmer regions. 117 99:59:59,999 --> 99:59:59,999 Here, the roofs are not designed to bear additionally heavy loads. 118 99:59:59,999 --> 99:59:59,999 They aren't designed for snow in winter for instance, 119 99:59:59,999 --> 99:59:59,999 so heavy silicon solar cells cannot be used for light harvesting, 120 99:59:59,999 --> 99:59:59,999 but these lightweight solar foils are very well suited. 121 99:59:59,999 --> 99:59:59,999 The bendability is important 122 99:59:59,999 --> 99:59:59,999 if you want to combine the solar cell with membrane architecture. 123 99:59:59,999 --> 99:59:59,999 Imagine the cells of the Sydney Opera as power plants. 124 99:59:59,999 --> 99:59:59,999 Alternatively, you can combine the solar foils 125 99:59:59,999 --> 99:59:59,999 with conventional construction materials like glass. 126 99:59:59,999 --> 99:59:59,999 Many glass [façade] elements contain a [foil] anyways 127 99:59:59,999 --> 99:59:59,999 to create laminated safety glass. 128 99:59:59,999 --> 99:59:59,999 It's not a big deal to add a second foil in the production process, 129 99:59:59,999 --> 99:59:59,999 but then the façade element contains the solar cell 130 99:59:59,999 --> 99:59:59,999 and can produce electricity. 131 99:59:59,999 --> 99:59:59,999 Besides looking nice, 132 99:59:59,999 --> 99:59:59,999 these integrated solar cells come along with two more important benefits. 133 99:59:59,999 --> 99:59:59,999 Do you remember the solar cells attached the roof I showed before? 134 99:59:59,999 --> 99:59:59,999 In this case, 135 99:59:59,999 --> 99:59:59,999 we install the roof first 136 99:59:59,999 --> 99:59:59,999 and as a second layer, 137 99:59:59,999 --> 99:59:59,999 the solar cell. 138 99:59:59,999 --> 99:59:59,999 This is adding on [the] installation cost. 139 99:59:59,999 --> 99:59:59,999 In the case of integrated solar cells, 140 99:59:59,999 --> 99:59:59,999 at the site of construction, 141 99:59:59,999 --> 99:59:59,999 only one element is installed, 142 99:59:59,999 --> 99:59:59,999 being at the same time the envelope of the building 143 99:59:59,999 --> 99:59:59,999 and the solar cell. 144 99:59:59,999 --> 99:59:59,999 Besides saving on your installation costs, 145 99:59:59,999 --> 99:59:59,999 this also saves resources 146 99:59:59,999 --> 99:59:59,999 because the two functions are combined into one element. 147 99:59:59,999 --> 99:59:59,999 Earlier I talked about optics. 148 99:59:59,999 --> 99:59:59,999 I really like this solar pattern, 149 99:59:59,999 --> 99:59:59,999 maybe you have different taste or different design needs. 150 99:59:59,999 --> 99:59:59,999 No problem. 151 99:59:59,999 --> 99:59:59,999 With the printing process, 152 99:59:59,999 --> 99:59:59,999 the solar cell can change its shape and design very easily. 153 99:59:59,999 --> 99:59:59,999 This will give the flexibility to architects, 154 99:59:59,999 --> 99:59:59,999 to planners and building owners 155 99:59:59,999 --> 99:59:59,999 to integrate this electricty-producing technology as they wish. 156 99:59:59,999 --> 99:59:59,999 I want to stress that this is not just happening in the labs. 157 99:59:59,999 --> 99:59:59,999 It will take seven more years to get to mass adoption, 158 99:59:59,999 --> 99:59:59,999 but we are at the edge of commercialization, 159 99:59:59,999 --> 99:59:59,999 meaning there are several companies out there with production lines. 160 99:59:59,999 --> 99:59:59,999 They are scaling up their capacities 161 99:59:59,999 --> 99:59:59,999 and so are we with the inks. 162 99:59:59,999 --> 99:59:59,999 This smaller footprint is much more comfortable. 163 99:59:59,999 --> 99:59:59,999 (Laughter) 164 99:59:59,999 --> 99:59:59,999 It is the right size, 165 99:59:59,999 --> 99:59:59,999 the right scale. 166 99:59:59,999 --> 99:59:59,999 We have to come back to the right scale when it comes to energy consumption. 167 99:59:59,999 --> 99:59:59,999 And making buildings carbon neutral is an important part here. 168 99:59:59,999 --> 99:59:59,999 In Europe, 169 99:59:59,999 --> 99:59:59,999 we have the goal to decarbonize our buildings [stock] until 2050. 170 99:59:59,999 --> 99:59:59,999 I hope organic photovoltaics will be a big part of this. 171 99:59:59,999 --> 99:59:59,999 Here are a couple of examples. 172 99:59:59,999 --> 99:59:59,999 This is the first commercial installation of fully printed organic solar cells. 173 99:59:59,999 --> 99:59:59,999 Commercial means that the solar cells were printed on industrial equipment. 174 99:59:59,999 --> 99:59:59,999 The so-called solar trees are part of the German pavilion 175 99:59:59,999 --> 99:59:59,999 at the World Expo in Milan in 2015. 176 99:59:59,999 --> 99:59:59,999 They provided shading during the day 177 99:59:59,999 --> 99:59:59,999 and electricity for the lighting in evening. 178 99:59:59,999 --> 99:59:59,999 You may wonder why this hexagonal shape was chosen for the solar cells. 179 99:59:59,999 --> 99:59:59,999 Easy answer: 180 99:59:59,999 --> 99:59:59,999 the architects wanted to have a specific shading pattern on the floor 181 99:59:59,999 --> 99:59:59,999 and asked for it, 182 99:59:59,999 --> 99:59:59,999 and then it was printed as requested. 183 99:59:59,999 --> 99:59:59,999 Being far from a real project, 184 99:59:59,999 --> 99:59:59,999 this free-form installation hooked the imagination of the visiting architects 185 99:59:59,999 --> 99:59:59,999 much more than we expected. 186 99:59:59,999 --> 99:59:59,999 This other application is closer to the projects 187 99:59:59,999 --> 99:59:59,999 and applications we are targeting. 188 99:59:59,999 --> 99:59:59,999 In an office building in Sao Paulo, Brazil, 189 99:59:59,999 --> 99:59:59,999 semi-transparent OPV panels are integrated into the glass façade, 190 99:59:59,999 --> 99:59:59,999 serving different needs. 191 99:59:59,999 --> 99:59:59,999 First, they provided shading for the meeting rooms behind. 192 99:59:59,999 --> 99:59:59,999 Second, the logo of the company is displayed in an innovative way. 193 99:59:59,999 --> 99:59:59,999 And of course electricity is produced, 194 99:59:59,999 --> 99:59:59,999 reducing the energy of the building. 195 99:59:59,999 --> 99:59:59,999 This is pointing towards a future 196 99:59:59,999 --> 99:59:59,999 where buildings are no longer energy consumers, 197 99:59:59,999 --> 99:59:59,999 but energy providers. 198 99:59:59,999 --> 99:59:59,999 I want to see solar cells seamlessly integrated 199 99:59:59,999 --> 99:59:59,999 into our building shells 200 99:59:59,999 --> 99:59:59,999 to be both resource-efficient and a pleasure to look at. 201 99:59:59,999 --> 99:59:59,999 For roofs, silicon solar cells will often continue to be a good solution, 202 99:59:59,999 --> 99:59:59,999 but to exploit the potential of all façades in other areas, 203 99:59:59,999 --> 99:59:59,999 such as sem-transparent areas, 204 99:59:59,999 --> 99:59:59,999 curved surfaces 205 99:59:59,999 --> 99:59:59,999 and shadings, 206 99:59:59,999 --> 99:59:59,999 I believe organic photovoltaics can offer a significant contribution 207 99:59:59,999 --> 99:59:59,999 and they can be made in any form architects and planners will want them to. 208 99:59:59,999 --> 99:59:59,999 Thank you. 209 99:59:59,999 --> 99:59:59,999 (Applause)