Effective solutions to solar energy:
An example of Brazil-Finnish
collaboration on nano solar cells
Peter Lund, Aalto University
[email protected]
Ana Flávia Nogueira, University of Campinas
Finnish-Brazilian Cooperation Seminar on Science, Technology and Innovation
Helsinki, 26 February 2013
Peter Lund 2013
Solar cells – status today
(solar cells= photovoltaics=PV)
80000
cumulative
installed/yr
60000
40000
20000
0
1977
1981
1985
1989
1993
1997
2001
2005
2009
Global cumulative PV, MWp
100000
year
Peter Lund 2013
35000
30000
25000
20000
15000
10000
5000
0
Yearly installed PV, MWp/yr
• Global: 0.5% of electricity, business $100+ billion, growth 30%/a
• Main PV technology: 90% silicon wafers, 10% thin films
• Challenges: (costs), materials, mass production
Solar cells – future opportunities
• Global: 5-25% of electricity (2050), business $200+ billion (2020)
• Main PV technology: mainstream materials, mass-produced, roll-toroll processes
20% of world electricity 2050
10%
$.3/Wp
$.5/Wp
$1/Wp
Ref Lund PD. Fast market penetration of energy technologies in
retrospect with application to clean energy futures. Appl Energy
(2010), doi:10.1016/j.apenergy.2010.05.024
Peter Lund 2013
Mass-produced flexible solar cells
Source: Janne Halme
Peter Lund 2013
3rd generation solar cells:
Flexible metallic nano-structured
dye-sensitized solar cells (DSC)
•
•
Advantages: potentially cheap, flexible, easy to prepare
Challenge: good efficiency, high stability, low cost simultaneously
G24i
Glass 2 – 3 mm
TCO 0.5 – 1 m
ePhotoelectrode
Dye
1.5 nm
5 – 20 m
TiO2
10 – 30 nm
e+
Electrolyte
I3
-
- 3I-
-
5 – 20 m
Pt
Peter Lund 2013
Counter
electrode
e-
TCO
Glass
The science behind the Project
(Mission: Find a material combination that fulfills good
efficiency, high stability, low cost)
Light + Steps 1-2-3-4-5-6-7 = Electricity from DSC
Steps 5-6-7 =Focus is Brazilian-Finnish Joint-Project
6. Electrolyte
7. Dye
regeneration diffusion
1. Light
absorption
2e3. Electron
collection
-
+
-
-
2e-
+
2. Electron
injection
2e5. Charge transfer
at counter electrode
2eApplication
Peter Lund 2013
4. Conduction
on substrates
Molecular redox couples and hole
conductors for all-printed solid-state
flexible dye solar cells (SOLID)
Academy of Finland
CNPq
•
Objective: Develop advanced electrolytes & novel redox couples to
be used as an electrolyte ink for printable large area dye solar cells
•
Complimentary: LNES group (Brazil) on semisolid and solid gel
electrolytes; NEW group (Finland) on printable sandwich DSC
•
Means: 4-year project(2013-), ca €400,000 funding, exchange
•
Results: Novel ink (cheap, stable, efficient) & academic merits
Peter Lund 2013
The path from science to society
How muchcould nano solar cells (DSC) bring in energy?
•
•
•
Photoactive materials required in DSC: 0.5-1 g/W; Substrate 20-70 g/W
Roll-to-roll mass production of flexible DSC on paper, plastic, steel (or glass)
Assume 20% of bulk material devoted to mass-production of DSC
Impact
SOLID- Project focus:
Science Technology Scale-up Mass production
Glass 2 – 3 mm
TCO 0.5 – 1 m
ePhotoelectrode
Dye
1.5 nm
5 – 20 m
TiO2
10 – 30 nm
e+
Electrolyte
I3-
-
- 3I-
5 – 20 m
Pt
e-
Counter
electrode
ink-jet, tape-casting, spincoating, doctor blade,
spraying, screen-printing,
silk-printing, roll-to-roll
TCO
Glass
All world energy = 7 years of production
time
Peter Lund 2013
Source: Kati Miettunen, Minna Toivola, Ghufran Hashmi, Jyri Salpakari, Imran Asghar, Peter Lund: A carbon gel catalyst layer for the roll-to-roll production of dye solar cells,
Carbon, 2010: PII: S0008-6223(10)00701-3 DOI: 10.1016/j.carbon.2010.09.052;.Miettunen, Kati; Halme, Janne; Toivola, Minna; Lund, Peter: Initial Performance and Stability
of Dye Solar Cells on Stainless Steel Substrates. Journal of Physical Chemistry C, 112, 4011-4017, 2008.