Firenze, 21 November 2014
Research on Renewables: a Case Study
Third generation solar cells: DSSC
Alessandro Mordini
CNR – Istituto di Chimica dei Composti Organometallici
Area di Ricerca di Firenze
Surpassing Energy Targets through Efficient Public Buildings
Firenze, Salone dei Dugento, Palazzo Vecchio
21 November 2014
Firenze, 21 November 2014
Research on renewable energies through a highly multidisciplinary
approach
«Design and Synthesis of new organic dyes for the production of non-conventional
solar cells»
from: May 2010 until April 2013
www.fotosensorg.unisi.it
«IRIS - Coloranti per l’energia e l’ambiente»
from: May 2012
iris.iccom.cnr.it
Firenze, 21 November 2014
2030Inc.
Energy
Outlook (BP)
Source: Innovative Clean Energy
(2008)
•
Humanity has constantly increased its energy need and
consumption.
•
Global energy consumption in 2010:12 Btoe = 139.600
TWh (+5.6% compared to 2009).
•
Most of this energy is produced by fossil fuel.
•
Result: resources shortage of fossil fuel resources
and atmospheric and environmental pollution.
•
Unless major and urgent changes are made in
supply/demand management of energy and/or
alternative Energies are made sufficiently available, the
maximum
supportable
worldwide
human
population level will peak between 2025 and 2050
Europe 2020 Initiative
1) -20% greenhouse gas emissions
2) +20% energy efficiency
3) ≥20% from renewable sources
http://ec.europa.eu/europe2020/index_en.htm
Firenze, 21 November 2014
SOLAR ENERGY IS FREE
AND PRACTICALLY INEXHAUSTIBLE
The volume of the spheres represents the
amount of energy potentially (although perhaps
not practically) available from every renewable
source, together with global consumption in
year 2010
Source: Perez et al. ,IEA/SHC, A
fundamental look at energy reserve in the
planet
Italy (16%) and Germany (32%)
combined accounted for nearly half
of global solar PV capacity
Source: Renewables 2013 Global Status Report
Firenze, 21 November 2014
a) Monocrystalline silicon
b) Polycrystalline silicon
Market share: ~ 80%*
Old generation
1) Silicon-Based Solar Cells
Optimized performances
Main Classes of Photovoltaic Cells
2) Thin Film Solar Cells
Market share: ~ 20%*
a) Bulk heterojunction solar cells (OPV)
b) Dye-Sensitized Solar Cells (DSSC)
*Source: EPIA (2010)
New generation
3) Organic and Hybrid Solar Cells
Non-optimized performances
a) GaAs
b) CdTe
c) CI(G)S – CuIn(Ga)Se2
d) Amorphous silicon (a-SiH)
Firenze, 21 November 2014
Record
DSSC
Firenze, 21 November 2014
DSSC have been invented in 1991 by the german chemist Michael Grätzel
at EPFL - Lausanne (Switzerland).
Main features- pros
Michael Grätzel
•
Good cells efficiencies (ηmax > 12%, lab scale).
•
Performances relatively independent by irradiation conditions.
•
Raw material easily available and low cost production.
•
Possible use of different supports (glass, polymeric materials).
•
Construction of either transparent or opaque cells in different colours.
Limitations- cons
•
Modules efficiency still too low (tipically between 6% and 9%).
•
Stability and lifetime, despite continuosly increasing, not satisfactory yet
(problems: corrosion, leak of material, degradation).
•
Limited number of practical applications (prototypes, small electronic
devices).
Firenze, 21 November 2014
Cost of module production
Production costs:
DSSC: 1.21 $/Wp (Solaronix, 2009)
c-Si:1.40-1.75 $/Wp (GTM Research, 2010)
Thin Films (CdTe): < 1 $/Wp (First Solar, 2011)
Energy Payback Time (EPBT)
Growth Rate Forecast
LCA analysis:
Major out-comes show that DSSCs
compare similarly and are sometimes
better than inorganic thin film devices,
even for a far-from-optimum industrial
fabrication procedure.
M. L. Parisi, S. Maranghi, R. Basosi Renew. Sust. Energ. Rev. 39 (2014)124–138
Raw materials:
Firenze, 21 November 2014
Japanese company Fujikura has performed detailed investigations on the relationship between
solar radiation and DSSC modules performances.
Light intensity
Incident angle
Temperature effect
Firenze, 21 November 2014
Due to their better performances under diffuse light, DSSC modules of the same nominal
power produce more energy compared to p-Si modules (approximately1.6 times higher on
the north wall).
Firenze, 21 November 2014
Accelerated tests with solar simulator
20.000 h = 2 y 103 d
In these conditions the duration of the test is assumed to correspond to a real utilization
lenght of 20 years – however, bear in mind this is only a simulation!
Firenze, 21 November 2014
Test under real conditions of use
Jsc
Voc
FF
η
After around 2.5 years module
efficiency was still above 80% of
the initial value
Deterioration factor:
 0.02% / day
N. Kato et al., Sol. Energy Mater. Sol. Cells 2009, 93, 893.
Firenze, 21 November 2014
Some commercial applications
backpack with small flexible DSSC panels for recharging batteries of
portable electronic devices (e.g. mobile phones, mp3 players etc.)
‘Folio’ Solar Keyboard a new iPad® cover
endowed with a DSSC-powered keyboard.
Hana Akari, Flower Lamp
Firenze, 21 November 2014
Forecasted growth of DSSCs in
different market segments
Source: IDTechEx report Dye Sensitized Solar Cells 2013-2023: Technologies, Markets, Players
Ease
transition
to:
EPFL, Lausanne
Building-Adapted PhotoVoltaics
Building-Integrated PhotoVoltaics
Firenze, 21 November 2014
BIPV: Building Integrated PhotoVoltaics
Toyota «Dream House», Aichi
CSIRO Energy Centre, Newcastle
House of the Future Prototype, OlympicVillage, Sydney
Firenze, 21 November 2014
EPFL Conference Center (Solaronix, CH)
Firenze, 21 November 2014
Geneva Airport (g2e, CH)
Prototypes of Solar Windows (Dyesol, AUS)
Firenze, 21 November 2014
Projet BIPV - Gare TGV de Perpignan
(ISSOL – Belgium)
See-through solar energy panel
(Sharp, Jpn)
Firenze, 21 November 2014
Renovation of MGM Hotel – Las Vegas
DSSCs mounted on Motorized Blinds over the
windows, power a DC motor and enable the
user to control the solar shading with the use of
a remote or wall mounted switch.
Firenze, 21 November 2014
Indoor application
Electronic Shelf Labels (ESL)
Update the prices daily via the RF
transmission technology
TV remote control
Sensors
Firenze, 21 November 2014
Glass
Electrolyte
Solution
(I-/I3-)
Transparent
Conductive
Oxide
Platinum
TiO2
Dye
Glass
Dye:
1. Improvement of light absorption and electonic transfer properties.
2. Simpler and more efficient synthetic procedures.
3. New dyes for transparent materials and for new colours.
TiO2: Studies on the morphology and size of nanopartcles; superficial modifications.
Electrolytic solution: Synthesis and application of (metall)organic compounds as an alternative
to the usual redox couple iodide/triiodide; studies on the use of non volatile solvents and solid
phase electrolytes.
Firenze, 21 November 2014
Mechanism
1.
Light absorption
2.
Photoexcitation
3.
Injection
4.
Charge
collection
5.
Electrolyte
reduction
6.
Regeneration
In the DSSCs the functions of photon absorption and charge
separation/ transport are made by different components.
Firenze, 21 November 2014
Dyes (sensitizer): ideal properties
a) Broad and efficient light absorption in the visible and near-infrared region (-conjugation).
b) Should have functional groups allowing a good anchoring on TiO2 (COOH).
c) Its energy levels should be correctly aligned to ease regeneration and electron injection.
d) It should not aggregate on the surface of the semiconductor (alkyl chains).
e) It should be thermally, chemically and photochemically stable.
f) For application in BIPV must be designed in different colours and transparency.
Test cells ready for stress
measurements
Firenze, 21 November 2014
Computational analysis
FEEDBACK
Design of new organic photosensitizers
Assembly of laboratory cells and efficiency measurements
Laboratory synthesis
Characterization
Firenze, 21 November 2014
Structural
design
supported by
TD-DFT
calculations
Donor Group
donor group
-Spacer
Acceptor Group
-spacer
•
•
•
acceptor
group
TiO2
Tuning of the energy levels and of the HOMO-LUMO gap
Influence on color (λmax), intensity of absorption (ε)
•
Increase in the
stability of the
dye/semicondutor
assembly
Influence on
electron transfer
and device lifetime
Firenze, 21 November 2014
Efficiency measurements
Compound
CDCA
best η (%)
DF13A
−
3.14
DF13B
+
3.24
DF13C
+
3.02
DF15
+
6.04
Desorption kinetics from TiO2
Cell stability over 1000 h
KOH 0.1 M in EtOH
Daniele Franchi, Massimo Calamante
Tetrahedron (Symposium-in-Print) 2014, 70, 6285
Firenze, 21 November 2014
2nd Generation dyes
•

510 < max < 521 nm in all cases.

Molar extinction coeffcients > 80000.
Clear improvement of the electronic, optical and
physico-chemical properties compared to previous gen.
TTZ3-5: Chem. Commun. 2014, DOI: 10.1039/C4CC06160H
Firenze, 21 November 2014
2nd Generation dyes
 Consistent with our aims: tests significant toward possible application in BIPV
 Simple fabrication: NO TiCl4 treatment, NO scattering layer, I−/I3− redox couple
 Thin TiO2 films: 5.5 μm (transparent) – 6.5 μm (opaque)
J-V curves
Stability Test
1000h ageing in the dark @ 85°C
•
Best cell efficiency:  = 7.39 - 7.71% for TTZ5 (transparent ad opaque cells, respectively).
•
Performances superior to reference dyes D5 (organic) and Z907 (Ru-based).
Daniele Colonna (C.H.O.S.E, Roma)
TTZ3-5: Chem. Commun. 2014, DOI: 10.1039/C4CC06160H
Firenze, 21 November 2014
Firenze, 21 November 2014
Research on renewable energies through a highly multidisciplinary
approach
«Design and Synthesis of new organic dyes for the production of non-conventional
solar cells»
from: May 2010 until April 2013
www.fotosensorg.unisi.it
«IRIS - Coloranti per l’energia e l’ambiente»
from: May 2012
iris.iccom.cnr.it
Firenze, 21 November 2014
Progetto FAR FAS 2014
Selfie: Sistema di Elementi avanzati multi Layer basato su superFici e materiali
Innovativi nanostrutturati per una Edilizia sostenibile ed energeticamente efficiente
Pannelli fotovoltaici di terza generazione integrati in architettura
Progetto POR FESR 2014-2020
Encolor Design: ENergia rinnovabile da pannelli fotovoltaici
COLORati architettonicamente integrati
Pannelli fotovoltaici di terza generazione integrati in architettura
Firenze, 21 November 2014
Progetto Smart Cities and Communities (MIUR)
Smartgate plus: Smart Solution for a Transparent, Efficient,
and more Sustainable Administrative Justice
Riqualificazione energetica di edifici di pregio sedi di tribunali amministrativi
Progetto Ente Cassa di Risparmio di Firenze
IRIS: Coloranti per l’energia e l’ambiente
Progettazione, preparazione e caratterizzazione di nuovi materiali per celle DSSC
Firenze, 21 November 2014
Acknowledgments
CNR-ICCOM
Università degli Studi di Siena
Dr. Gianna Reginato
Dr. Lorenzo Zani
Dr. Massimo Calamante
Dr. Grabriella Barozzino
Alessio Dessì
Bianca Cecconi
Daniele Franchi
Damiano Cirri
Ottavia Bettucci
Giovanna Burgio
Rocco De Lorenzo
Matteo Bessi
Marco Monini
Prof. Maurizio Taddei
Dr. Fabrizia Fabrizi de’ Biani
Prof. Riccardo Basosi
Dr. Adalgisa Sinicropi
C.H.O.S.E - Università di Roma «Tor Vergata»
Prof. Aldo di Carlo
Dr. Daniele Colonna
«FOTOSENSORG» Project
(2010-2013)
Funding
Dr. Maurizio Peruzzini
Università degli Studi di Firenze
Prof. Mara Bruzzi
Dr. Riccardo Mori
Michele Spatola
Prof. Roberto Bianchini
Dr. Marco Corsi
Dr. Marco Bonanni
«IRIS» Project (2013-2015)
Progetto Premiale
«Energia da fonti rinnovabili»
24
Richiamo a serpente
Building trasparenti: importanza
Firenze, 21 November 2014
Firenze, 21 November 2014
Photovoltaic Cell: a device capable of converting sunlight into electricity
Main classes of photovoltaic cells:
Silicon-Based Solar Cells
Thin Film Solar Cells
Organic and Hybrid Solar Cells
•Monocrystalline silicon
•GaAs
•Polycrystalline silicon
•CdTe
•CI(G)S – CuIn(Ga)Se2
•Amorphous silicon
•Organic solar cells (OSC)
•Dye-Sensitized Solar Cells (DSSC)
•Perovskite Solar Cells
Old generation
New generation
Optimized performances
Pmax
Non-optimized performances
Jsc· Voc· ff
Mettere
performance
Pmax: maximum power produced by the cell
s
Efficiency: η =
Pin
=
Pin
Pin: power of incident solar radiation
It should always be coupled with a good stability!
Current/Voltage
(J/V) curve
Firenze, 21 November 2014
Dyes (sensitizer): design, synthesis and characterization
A multidisciplinary approach
Progetti in corso, citare horizon 2020 e
serpente, regione, comune…
DSSC: Progetti in corso
Progetto Smart Cities and Communities (MIUR)
Smartgate: Giustizia Amministrativa
Riqualificazione energetica di edifici di pregio sedi di tribunali amministrativi
Palazzo spada, Roma
Sede dell Consiglio di Stato
Progetto Nazionale in corso di valutazione
1° Forum Internazionale, Sviluppo Ambiente Salute, Arezzo, 22.11.2012
Firenze, 21 November 2014
Main Classes of Photovoltaic Cells
1) Silicon-Based Solar Cells
a) Monocrystalline silicon
b) Polycrystalline silicon
Market share: ~ 80%*
2) Thin Film Solar Cells
a) GaAs
b) CdTe
c) CI(G)S – CuIn(Ga)Se2
d) Amorphous silicon (a-SiH)
Market share: ~ 20%*
3) Organic and Hybrid Solar Cells
a) Bulk heterojunction solar cells (OPV)
b) Dye-Sensitized Solar Cells (DSSC)
*Source: EPIA (2010)
Firenze, 21 November 2014
Dyes (sensitizer): ideal properties
a) Broad and efficient light absorption in the visible and near-infrared region (-conjugation).
b) Should have functional groups allowing a good anchoring on TiO2 (COOH).
c) Its energy levels should be correctly aligned to ease regeneration and electron injection.
d) It should not aggregate on the surface of the semiconductor (alkyl chains).
e) It should be thermally, chemically and photochemically stable.
f) For application in BIPV must be designed in different colours and transparency.
The development of this technology is well suited for small and medium size
companies dealing with all the manufacturing indicated below
CELLS PRODUCTION
Glass manufacturer
Supports (plastic, metal)
Electrodeposition
Semiconductor
Cell printing
APPLICATION
Housing components
Furniture
Accessories
Lamps
Doors, windows….
INNOVATION IN DESIGN
Opportunity for coupling
made in Italy and technology
DSSC: Materials and Structure
Glass
Electrolyte
Solution
(I-/I3-)
Transparent
Conductive
Oxide
Platinum
TiO2
Dye
Glass
1.
2.
3.
4.
5.
6.
7.
Components
Glass substrate
TCO layer (transparent conductive oxide)
Nanocrystalline semiconductor (TiO2)
Dye (adsorbed on the semiconductor)
Electrolyte solution
Counter electrode (usually Pt)
Glass substrate
http://www.solarprint.ie/images/dssc.jpg
Alessandro Mordini– EUSEW, Bruxelles, 22.06.2012
7/13
DSSC: Mechanism
Mechanism
1.
Light absorption
2.
Photoexcitation
3.
Injection
4.
Charge collection
5.
Electrolyte reduction
6.
Regeneration
Nelle DSSC il processo di assorbimento della luce e quello di separazione/trasporto dei
portatori di carica sono svolti da due componenti distinti.
Alessandro Mordini– EUSEW, Bruxelles, 22.06.2012
7/17
Solar radiation spectrum
Solar radiation should be adsorbed in the visibile and near infrared.
Alessandro Mordini– EUSEW, Bruxelles, 22.06.2012
2/17