11 po-tsung hsieh ok

Performance of bifacial module of

n-PERT cells

Po-Tsung Hsieh

Motech Industries, Inc.

May 26, 2014

PT Hsieh, bifi PV Workshop, May 26 2014Page 2 PT Hsieh, bifi PV Workshop, May 26 2014 2

Motech Industries, Inc.

Motech AmericasNewark, DE, US

Taipei, Taiwan

Itogumi MotechHokkaido, Japan

Motech (Suzhou)Kunshan, China

Tainan, Taiwan

No.6 solar cell producer in the world

PT Hsieh, bifi PV Workshop, May 26 2014Page 3 PT Hsieh, bifi PV Workshop, May 26 2014

Outline

Introduction

Cell Improvements

N-PERT Hybrid Cell

Module Performance

Conclusions

PT Hsieh, bifi PV Workshop, May 26 2014Page 4

Outline

Introduction

Cell Improvements

N-PERT Hybrid Cell

Module Performance

Conclusions

PT Hsieh, bifi PV Workshop, May 26 2014Page 5 PT Hsieh, bifi PV Workshop, May 26 2014

Year/Conference 20132013

EUPVSEC2014nPV

2014nPV

2014 nPV

2013 EUPVSEC

2013EUPVSEC

2014bifiPV

Company/Institute LG BOSCH INESISC

KonstanzISFH ECN PVGS Motech

Junction Front Front Front Front Front Front Front FrontStructure Bifacial Bifacial Bifacial Bifacial Bifacial Bifacial Bifacial Bifacial

Efficiency 21 20.7 20.5 20.3 20.3 20.23 20.16 20.73

Bifacial nPERT Efficiency

nPERT = n-type Passivated Emitter, Rear Totally diffused

Rear junction, Monofacial: Q Cells, IMEC

Front junction, Monofacial: ISFH, Bosch, Suniva

Front junction, Bifacial: ECN, Bosch, Motech…

PT Hsieh, bifi PV Workshop, May 26 2014Page 6 PT Hsieh, bifi PV Workshop, May 26 2014 6

Outline

Introduction

Cell Improvements

N-PERT Hybrid Cell

Bifacial Module Performance

Conclusions


Emitter Improvement

Performance of different boron emitters QSSPC on symmetric monitor wafers Improved cell efficiency with optimized boron emitter


Front Side Paste

Voc(mV)

Jsc (mA/cm2)

FF(% abs)

Eff(% abs)

A2-A1 0.2 0.20 1.4 0.4 A3-A1 0.3 0.17 1.7 0.5

Paste selection strongly impacts FF


Improvements Combined

Achieved >20.7% cell efficiency

Independently measured by ITRI’s Solar cell Calibration and Characterization Laboratory (SCCL) metal coated chuck

Voc Jsc FF Eff

647 39.2 81.76 20.73


nPERT Benefits

Pmax Voc JscnPERT -0.36 -0.29 0.045

p-mono -0.42 -0.33 0.040

Superior temperature coefficients

Absence of LID

Superior low light performance


Bifaciality

Bifaciality = (Rear Eff) / (Front Eff) Less polished: 88.5% More polished: 85.7%

Depend on applications: Vertical module installation High bifaciality Standard module installation Higher front-side efficiency

Est. total efficiency=front eff.+0.2*rear eff.


Outline

Introduction

Cell Improvements

N-PERT Hybrid Cell

Module Performance

Conclusions


Bosch (2013 EUPVSEC_2BV 2.54)

nPERT Hybrid Cell

Potential of n-Hybrid cell process Higher throughput for implant Less process steps


Motech: n-Hybrid Cell

Relative gain vs. BKM n-PERT cell

Advantages of n-Hybrid Cell: Potential for higher efficiency Lower total cost per watt


Outline

Introduction

Cell Improvements

N-PERT Hybrid Cell

Module Performance

Conclusions

PT Hsieh, bifi PV Workshop, May 26 2014Page 16 16

~30% output gain for nPERT bifacial module (60 cells):

320W effective output as compared with p-mono reference

module.

p-mono reference module(246W)

nPERT bifacial module

n-PERT Bifacial Module



Higher PR gain in morning and evening (standard installation)

PT Hsieh, bifi PV Workshop, May 26 2014Page 18 18

~20% bifacial gain from bifacial module in outdoor test


Monofacial module

Bifacial module


Outline

Introduction

Cell Improvement

N-PERT Hybrid Cell

Module Performance

Conclusions


nPERT bifacial cells produced with industrial fabrication processes achieved cell efficiency > 20.7% potential of n-Hybrid cell

nPERT module field test provided for modules with effective power output 320W >20% of PR gain for bifacial module

Conclusions


Important steps for future development in cell/module level Higher efficiency Quantify the benefits measurements standard Optimize module and system design for bifacial cells

Conclusions


Team members:Chih-Jeng Huang, Hung-Chih Chang, Wei-Cheng Mo, Shu-Hung Yu, Chi-Chun Li

Cell and Module measurements Solar cell Calibration and Characterization Laboratory (SCCL), Industrial Technology Research Institute (ITRI) of Taiwan

Acknowledgement

PT Hsieh, bifi PV Workshop, May 26 2014

Thank You

for Your Attention

Presentations & Public Speaking

11 po-tsung hsieh ok