Li ght Concent r at or Sunl i ght
Sol ar Cel l
Hydr ogen Fuel
Mohammad H. Hashemi Optics Lab, IMT, EPFL SHINE Annual Meeting Bern, 2015
Fl ui di cs
Wat er Spl i t t i ng
shine.epfl.ch
Developing cost-based design rules
Rodriguez, et al. "Design and cost considerations for practical solar-hydrogen generators." Energy & Environmental Science, 2014
Optimizing Solar-Hydrogen Production
Small Large electrolyzer electrolyzer Optimal electrolyzer
Spanni ng a br oad r ange of sol ar - H2 syst ems
Dumortier & Haussener, in progress
H2 Cost and Sust ai nabi l i t y Consi der at i ons
Current
I mpr ovi ng l ong- t er m per f or mance
Voltage
1.9 V
Voc of Si cel l s shoul d i ncr ease t o have a
I ncr eased vi abi l i t y f or Si devi ces
Increasing the VOC of Si based PV cells from 1.9 V to 2.3 V significantly improves the outputs of the devices
Component s Over vi ew Li ght Concent r at or Sunl i ght
Sol ar Cel l
Hydr ogen Fuel
Fl ui di cs
Wat er Spl i t t i ng
Si l i con PVs f or Wat er Spl Solar i t t i Application ng as Thin-Film Silicon Triple-Junction
photocathode
Cells
Glass
SiOx
TCO Front: ZnO aSi (p-i-n) i-aSi ucSi (p-i-n)
SiOx ZnO Ti/Pt
Current status at CSEM: Ρ=11.3 % at 1 sun; Voc = 2.23 V Potential sun to fuel efficiency: SFE=8.1%
Sel f Tr acki ng Concent r at or Lens array Waveguide Dichroic mirror membrane Phase change actuator
Zagolla, et al. "Self-tracking solar concentrator with an acceptance angle of 32째." Optics express, 2014
Concentrated Water-Splitting Device
Mi ni at ur i zed Membr anel ess El ect r ol yzer
O2
Hashemi, et al. "A membrane-less electrolyzer for hydrogen production across the pH scale.“ Energy & Environmental Science, 2015
H2
Hi gh per f or mance acr oss t he pH scal e 1 M Sulfuric Acid with Pt Electrodes
1 M Neutral and Basic Electrolytes
Phot oact i ve component s and scal e- up Demonst r at i on of a Phot oact i ve Devi ce
Lar ge Scal e I mpl ement at i on
Goi ng f r om l i qui d t o vapor oper at i on
Modestino, et al. "Vapor-fed microfluidic hydrogen generator." Lab on a Chip, 2015.
Current Density [mA/cm2]
10
Opt i mi zi ng per f or manc e f or sol ar oper at i on • Incorporating photo-
8
active electrodes – Low operating
6
currents
• Need to lower
electrochemical load • Better catalysts • Reduce ionic resistance
4
2
0 0
1
Potential [V]
2
3
I ncor por at i ng mi cr ost r uct ur ed phot ocat hodes
Project Achievements Scientific output: • 4 Patents • 10 Journal Publications Awards: • Foreign Policy Magazine's “100 Leading Global Thinkers” Prize • 2015 Energy and Environmental Science Readers' Award Lectureship • Best Student Presentation Award from the OSA, Energy and the Environment Congress
Acknowledgements SHINE Team Light Concentration (EPFL): C. Moser (PI), V. Zagolla Optofluidics (EPFL): D. Psaltis (PI), M. Modestino Modeling (EPFL): S. Haussener (PI), M. Durmotier, S. Tembhurne Photovoltaics (CSEM): J. Bailat (PI), D. Domine Catalysts (EMPA): A. Braun (PI), D. Bora
for tomorrow.
Thank You shine.epfl.ch