METU Hücre Teknolojilerinde Mevcut Durum

METU

Introduction solar energy

Crystalline Si solar cells

Standard cell structure

New approaches

GÜNAM as a center of excellence for solar energy conversion

Conclusions

Outline

METU Güzel Haber

Lowest price offered

October 2017

1.78 c$/kWh

Bu dalganın önünde hiç kimse duramayacak

METU Photovoltaic Solar Cells

A photovoltaic device is an electronic device A PV device is a two terminal device like a diode A single solar cell generates a voltage in between 0.5 – 1 V.

METU Some history

• In 1954, D.M. Chapin, C.S. Fuller and G.L. Pearson, of Bell Laboratory, announced first solar cell silicon-based solar cells.

• 1955, the Hoffman Electronics-

Semiconductor Division announced the first commercial photovoltaic product that was % 2, priced at $25 per cell, at 14 mW each, or $1,785 per watt.

• By the mid-1960s, efficiency levels were nearing 10 percent.

• As an outgrowth of the space exploration in the 1960s-70s.

METU

6

Evolution of Best Cell Efficiency Values

METU Crystal Si based solar cells

Single crytsalline Multicrystalline

Heterojunction (HIT- Heterojunction with

Intrinsic Thin layer) (sadece Sanyo)

Module efficiency : %15-20 Module efficency: %15-17

Market share > % 90

Module efficency : %16-20

7

METU Thin film solar cells

Module Efficiency: %13-15 Module Efficiency : %13-15 Module Efficiency : %8-10

8 Market Share <%10

METU

Kaynak : Oerlikon

Thin Film Solar Modules

METU Is Solar Electricity still Expensive ?

Ankara 5 c$/kWh

ITRPV report, 2014

Minimum system price in Turkey =

900 $/kWp

Elektriğin Perakende satışı : 35 krş = 10 c$/kWh

METU Solar Electricity is Becoming the Cheapest

Electricity

Konya Karapınar YEKA tender for 1000 MW power station, 6.99 c$/kWh has been realized

Tender was won by Q-Cells-Hanwha-Kalyon group

Lowest price (Abu-Dabi tender) September 2016

2.42 c$/kWh

Now in Saudi Arabia October 2017

1.78 c$/kWh

Recent results of tenders

METU Solar Module Prices Falling Down

Module price in Turkey : 40 c€/Wp

METU

*

Total installation exceeded 320

GW at the end of 2016

In 2017, 80 GW additional

installation is expected

PV Installation is Increasing Beyond Expectations

METU Champions of Solar electricity

14

Percentage of the solar electricity in total consumption

Total PV capacity in Turkey : 1000 MW.

This generates 1.5 TWh/year Corresponding

to

= % 0.5 of the total electricity generation

Source : PVPS report 2017

METU

15

*Taş devri taş bittiği için sona ermedi, petrol çağı da petrol bitmeden çok önce sona erecek

*

A vision

to be realized,

… hopefully soon

METU

Crystalline Si solar cell …

METU Crystal Si Value Chain

17

200-300 M$ 12-16 M$ 12-15 M$

13-50 M$ 6-9 M$ 1 $/Wp

Quartz Silicon Ingot Wafer

Solar Cell Module System Electricity

Fabrication of solar cell consists of R&D

intensive processes. Industry can not survive without a true R&D

support.

METU C-Si Solar Cell Fabrication on Standard

p-type Si Wafer

Mono-Crystal Multi-Crystal

156mm

156mm

p

n

SiN Ag Ag

Al p+

METU Maximum Efficiency Limit

19

Asumptions : Single junction is used. Temperature is 300 K

New approaches are needed to approach and/or exceed the

Shockley-Queisser limit

For Si solar cells, the maximum achievable efficiency is about % 29

METU

Limitations : Electrical and Optical

Crystalline Si solar cell Efficiency

Record efficiency at R&D level %26.7

Industrial Efficiency %18-23

Si limit %29

We can gain up to % 6-11 at industrial level

Status of Si solar cells

METU Losses in Crystalline Si Solar Cell

Rolf Brendel et al, Prog. Photovolt: Res. Appl. (2015)

h = 28.5 %

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22

Standard Technology (Al-BSF c-Si

cells)

High Efficiency Concepts • Selective Emitter • PERC, PERL, PERT • Bi-Facial • Back Contact (IBC) • Passivated Contacts • TOPcon cell • Dopant free cells (DASH) • Tandem cells with new

materials like pervoskites

Low Cost Concepts

• Multi – C • UMG Si • Quasi Mono – C • Thin Silicon

Future Low Cost + High

Efficiency

New approaches in c-Si Solar cell Technology

METU

Main problems and losses:

Homogeneous highly doped emitter results in high Auger recombination Low Voc

Fully metallised back surface results in high back surface recombination velocities Low Voc

Back Al also results in parasitic absorption in IR

region Low Jsc

Light induced degradation due to B-O related defects in p-type base

Standard Technology – Full

Al:BSF

23

p-type

Al p+ Al:BSF

Ag SiNx

n+

METU

Passivated Emitter Rear Cell

Back surface is coated with a dielectric passivation layer

Metal contacts are taken from local

opening on rear passivation layer

Less Metal-Si interface on back side Less back surface recombination Higher Voc 21.2% efficiency recorded industrial size*

PERC Technology

24 *Rolf Brendel et al, Prog. Photovolt: Res. Appl. (2015)

METU PERC Technology

25

Projection Realization

PERC Cells are becoming industry standard

METU High Efficiency Solar Cells :

Heterojunction c-Si Technology

e-

h+

Low temperature deposition conditions (>200C°).

Excellent surface passivation by hydrogenated amorphous Si layer.

Contacts are removed from c-Si surface.

Thin wafers ~100um are utilizable!

Good temperature coefficient

Extremely high Voc ~750mV

High efficiency

METU

High Efficiency Solar Cells Interdigitated Back Contact (IBC) Cells

-Homojunction case

Interdigitated Back Contact (IBC) cISFH

aA. Halm et al., in 27th European Photovoltaic Solar Energy Conference and Exhibition, Frankfurt, Germany, 2012 bA. Mewe et al., 42nd IEEE Photovoltaics Specialists Conference, New Orleans, USA, 2015 chttp://www.isfh.de/institut_solarforschung/ionenimplantierte-ibc-zellen.php?_l=1 dR. Müller et al., in 4th International Conference on Silicon Photovoltaics, SiPV2014

156-156mm2

Eff: 22.1%/Voc: 676.2mV Jsc:41.6mA/cm2/FF:78.5%

Interdigitated Back Contact (IBC) bECN-Mercury Cell Concept

Interdigitated Back Contact (IBC) aKonstanz-Zebra Cell Concept

Idnterdigitated Back Contact (IBC) dFraunhofer ISE

METU

Interdigitated Back Contact (IBC) SunPower

Homojunction IBC (Industry)

module eff:24.2% (2017-record)

Interdigitated Back Contact (IBC) Trina Solar

brecored cell eff: 23.5% 156x156mm2/screen printed process

ahttps://www.pv-tech.org/news/sunpower-hits-average-cell-conversion-efficiencies-of-25-at-fab-4 bhttps://www.pv-magazine.com/2016/04/26/trina-solar-sets-new-ibc-cell-efficiency-record_100024306/

aindustrial line av. cell eff: 25% (2017-record)

METU

Interdigitated Back Contact (IBC) cFraunhofer ISE-TOPCon

High Efficiency Solar Cells -Heterojunction/Passivating Contact IBC

Back Contacted SHJ aEPFL

PolySi Passivating Contact IBC bDelft University

Heterojunction IBC dPanasonic HIT Cells

aA. Tomasi, IEEE Journal of Photovoltaics, vol. 4, no. 4, pp. 1046-1054, 2014 bY. Guangto, Solar Energy Materials and Solar Cells, vol. 158, pp. 84-90, 2016 cC. Reichel, in 29th European PV Solar Energy Conference and Exhibition, Amsterdam, The Netherlands, 2014 dhttp://news.panasonic.com/global/press/data/2014/04/en140410-4/en140410-4.html ehttp://www.kaneka.co.jp/kaneka-e/images/topics/1473811995/1473811995_101.pdf

Heterojunction IBC eKaneka & NEDO HJ Cells

cell eff:26.33% (180cm2) (Sep.2016- new record)

METU Best Cell Efficiencies-Hetorojunction IBC

aK. Masuko et al., IEEE Journal of Photovoltaics, 4, 1433 (2014) bD. Adachi et al., Applied Physics Letters, 107, 233506 (2015) cM. Taguchi et al., IEEE Journal of Photovaoltaics, 4, 96 (2014) dhttps://www.helmholtz-berlin.de/media/media/projekte/hercules/hercules-m36-workshop/yoshikawa-kaneka-2016-hercles-designated-version.pdf

Voc [V] Jsc [mA/cm2] FF% Efficiency % Area*[cm2] Cell type

aPanasonic 0.740 41.8 82.7 25.6 143.7 (da) SHJ-IBC

bKaneka 0.738 40.8 83.5 25.1 151.9 (ap) SHJ

cPanasonic 0.750 39.49 83.2 24.7 101.8 (ta) SHJ

dKaneka 0.744 42.25 83.78 26.33 180.43(da) SHJ-IBC

METU

James Bullock et al. DOI: 10.1038/NENERGY.2015.31

Dopant-free Asymmetric

Heterocontacts (DASH) Solar Cell

METU GÜNAM : a global research center on solar

energy conversion

METU

GÜNAM is 8 years old

Mission : to develop fundamental and applied knowledge on

solar energy conversion for the benefit of the society in a global

context

GÜNAM is being supported by Ministry of Development

Total investment by the end of 2017 will exceed 15 Million USD

GÜNAM is the most comprehensive R&D center on solar energy

in the whole eastern mediterenaen region

http://www.gunam.metu.edu.tr/

GÜNAM : a global R&D center on solar energy

METU

Research Outputs

National/International articles Conference presentation Citation Thesis (MSc and PhD) Book/Chapter in a book Awards Patent Spin off company Event organization (Summer School, workshop)

192 78

801 59 5 2 1 1 9

Projects

National Projects International Projects University-Industry Joint Project

46 15 10

Total 71

External Supports Generated ( end of 2016)

National projects International projects University- Industry project supports

43.628.798,63 TL 3.767.151,22 TL 1.791.854,52 TL

Total ≈ 50.000.000 TL 14.200.000 $

Collaborations

National Internationals

32 24

Human Capital

Academician (affiliated to GÜNAM) Graduate students (MSc and PhD): Technical and administrative staff members

23 66 14

Total 103

GÜNAM in Numbers

GÜNAM is 8 years old

METU

c-Si Solar Cell Research Lab (With Physics Dpt.)

Thin Film Solar Cell Research Lab (With Physics Dpt.)

Organic and DSSC Solar Cell

Research Lab (OPV) (With Chemistry and Materials Eng. Dpt.)

Solar Thermal Power Lab. (ODAK)

(With Mechanical Eng. Dpt.)

GÜNAM Laboratories

Nanomaterials Research Laboratory

(With Materials Eng. Dpt.)

Outdoor Test Platform (With Physics Dpt.)

METU GÜNAM’s Expansions

3500 sqm lab space

500 m2 clean room with various classes

Connected to other research centers at

the new research park of METU

Close to the METU technology

development region

METU Research Park

METU Research Park Complex

A unique R&D line based on c-Si solar cells

for industry-university collaboration

Built for MILGES project

100 – 500 w/h throughput

All C-Si solar cell technologies can be

developed fabricated at this facility : Al-

BSF, PERC, PERT, Bi-facial cells, IBC

Can be an R&D center for national

projects like Karapınar Project

Under construction (to be completed in 2018-2019)

Fully operational in November 2017

METU GÜNAM C-Si Solar Cell Laboratory

• Capable of fabricating mono- and multi-crystalline Si solar cell with industrial size.

• 1000 and 10000 class clean rooms

Assist.Prof Dr. Selçuk Yerci

Prof Dr. Raşit Turan

METU

19.0%

4” full wafers

156mm x 156 mm wafers

small samples

2 Busbars

3 Busbars

18.2%

20.0% n-Bificial

p-PERC Al:BSF

4 Busbars

Al:BSF PERC

01-2009 04-2009 10-2009 04-2010 12-2010 06-2010 08-2011 10-2011 11-2011 12-2012 04-2014 02-2015 05-2016 12-20170

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10

12

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18

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Effic

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cy (

%)

Date

HIT and IBC

GÜNAM Evolution on c-Si Solar Cell

METU Integration to Europe through

projects and networking

Project’s name Researcher Project’s Subject

EU-SOLARIS Raşit Turan

Derek Baker Solar Thermal Electricity (CSP)

FOCUS Alpan Bek Material Science for PV

NANODEV Burcu Akata Kurç Solar Energy/Biosensor

CHEETAH Rasit Turan Photovoltaics

GÜNAM is a member of European Energy Research Allience

Low cost , more power

GÜNAM is at the Steering Committee of European Photvoltaic Technology Platform

METU

Announcement

METU Thank you for your attention

Visit www.gunam.metu.edu.tr

41

METU

A single junction solar cell can use

only some part of the solar radiation

Solar radiation and limitations AVERAGE INSOLATION Average insolation just outside the atmosphere : 1366 W/m2

One can convert 1/3 of solar

radiation using a single junction Si solar cell !

Thermal Losses

Infrared Losses