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John Berdner, SolarEdge

General Manager for North America

Field Results of Energy Maximizing

Distributed DC Topology –

Residential & Commercial Installations

8. September, 2010

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System Energy Loss

Module mismatch

Partial shading

Undervoltage/Overvoltage

Dynamic weather MPPT loss

Energy Loss Factors in Traditional PV Systems

Design Energy Loss

Limited roof utilization due

Indirect Energy Loss

No module level monitoring

©2010 SolarEdge

to design constraints

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Power Optimizer

SolarEdge System Overview

Inverter

Monitoring Portal

Module level optimization

Fixed voltage - ideal installation

Module level monitoring

Enhanced safety solution

InternetMonitoring Server©2011 SolarEdge

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SolarEdge Distributed Technology

©2010 SolarEdge

ASIC-based Power Optimizers achieve:

Per-module Maximum Power Point Tracking (MPPT)

Efficiency: 98.8% EU weighted (99.5% peak)

Conversion modes: buck, boost and buck/boost

Wide module compatibility: 5v-125v, up to 400w

Power Line Communication transceiver

Module shut-down unless connected to an operating inverter

250/300/400W

Module Add-on

250/350W Module

Embedded

350W Thin Film

Module Add-on

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String voltage is always fixed, regardless of temperature and string length

Flexible design for increased roof utilization:

⁻ Parallel strings of unequal lengths

⁻ Modules on multiple roof facets

⁻ Modules with different power ratings

⁻ Modules of different technologies

Longer strings lead to savings on wiring and BoS components

String voltage is always optimal for DC/AC conversion

High inversion efficiency: VDC ≝ VAC·√2+ε

Prevention of under/over voltage situations

Inverter cost reduction

Fixed String Voltage - Enabler

©2010 SolarEdge

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Field Trials and Results

©2010 SolarEdge

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25 Suntech 280W modules 34 Suntech 210W modules 4 Suntech 185W modules One power optimzier per

module 3 SolarEdge SE5000 inverters 1 string per inverter:

20, 20, 23 modules

©2010 SolarEdge

Roof Utilization Case Study – Israel

Optimal roof space utilization enabled a 15kW residential installation Four facets covered Unmatched modules in each string were necessary:

Different module sizes (and rating) Different tilt and azimuth

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280w

East

210w

East

280w

West

210w

West

280w

West

210w

West

280w

East

210w

East

Module-level monitoring reveals: No mismatch losses (module-level MPPT) No string mismatch losses (length agnostic fixed string voltage)

Attractive 5.1 kWh/kWp per day during August (compared to 5.5 for South-only sites)

©2010 SolarEdge

Roof Utilization Case Study – Results

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Side by side energy comparisons under similar conditions:

Standard inverter compared to distributed system

Both systems subjected to:

Identical total DC capacity (otherwise comparing kWh/kWp)

Identical module tilt and orientation

Identical irradiance and temperature conditions

Identical shading scenarios

Comparative Energy Case Study Methodology

Traditional system Distributed system©2010 SolarEdge

Power

Optimizer

Power

OptimizerPower

Optimizer

Power

Optimizer

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Comparative Case Study 1 - Italy

©2010 SolarEdge

Power optimizers + SE5000 compared to four traditional inverters of various brands (5kW, 5kW, 3kW, 6kW)

Comparison without shading, and with simulated shading. Experiments done by Albatech, a MetaSystem Group company, an Italian

MW-scale turn-key integrator, and a technology oriented PV distributor.

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Under unshaded conditions distributed system produced 2.3% - 6.4% more energy than the traditional inverters

0.00

10.00

20.00

30.00

40.00

50.00

60.00

kW

h

Energy Production 06-15 July 2010

©2010 SolarEdge

Comparative Case Study 1 – Unshaded

Po

we

r O

pti

miz

ers

+ S

E5000

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SolarEdge

Distributed

System

A cardboard panel was used to simulate a chimney-like sliding shadow on 1-2 modules in each string with a distributed system and inverter A

The best performing inverter of three other un-shaded traditional inverters was used as a reference

©2010 SolarEdge

Comparative Case Study 1 – Shaded

Inverter A

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In reference to the unshaded inverter: The distributed system recovered more than 50% of the energy lost by traditional inverter A due to shading (-4% vs. to -8.63%)

©2010 SolarEdge

Comparative Case Study 1 – Shaded (Cont.)

5.435.20 5.21 5.27

5.65

0.00

1.00

2.00

3.00

4.00

5.00

6.00

kW

h

Shaded UnshadedP

ow

er

Op

tim

izers

+ S

E5000

* Inverter B was disconnected due to a technical issue during this test

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Comparative Case Study 2 – Czech Republic

©2010 SolarEdge

Power optimizers + SE5000 compared to 5kW inverter of a leading brand Each inverter connected to 2 strings x 12 AWS modules x 185w = 4.4kWp Three partly shaded modules in each string of each system A third system remains unshaded for reference Test performed by American Way Solar, one of CZ largest PV distributors

Unshaded reference

Shaded SE5000

Shadedtraditional

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63.1258.96

45.25

0

10

20

30

40

50

60

70

1 2 3

0

2

4

6

8

10

12

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Power Optimizers + SE5000Traditional Inverter

Dai

ly e

ner

gy, k

Wh

Tota

l en

erg

y, k

Wh

©2010 SolarEdge

Comparative Case Study 2 – Results

The distributed system produced 30.3% more energy than the traditional inverter (58.96 kWh vs. 45.25 kWh)

In reference to the unshaded inverter, the distributed system recovered 77% of the energy lost by the traditional inverter due to shading (6.5% loss vs. 28.3% loss)

ShadedUnshadedShaded

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Power optimizers + SE5000 compared to traditional 5kW inverter with multiple MPP trackers

2 string x 12 and 13 Solon P210 modules x 210w = 5.25kWp A section inside a large scale PV field No shading

©2010 SolarEdge

Comparative Case Study 3 - Germany

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The distributed system produced 1.65% more energy than the traditionalinverter

On days with dynamic weather conditions, distributed module-level MPPTrecovers energy otherwise lost due to delayed MPPT process

Power Optimizers + SE5000

Traditional Inverter

Module-level MPPT energy gain on that day: +2.9%

Power

©2010 SolarEdge

Comparative Case Study 3 - Results

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As shown in comparative case study 3, moving clouds induce rapidfluctuations in irradiance level

Centralized inverters are

more limited in their ability

to track changes in Imp

as fast as they occur,

compared to module-level

MPP trackers

©2010 SolarEdge

The Impact of Dynamic Weather Conditions

±3kW fluctuations exhibited

for a 5kW inverter in the

span of minutes

10:00 – 11:00

Sep 2nd 2010

19©2010 SolarEdge

Power optimizers + SE5000 compared to traditional 5kw inverter with several MPP trackers

2 strings x 9 Trina TSM220 modules x 220w = 3.96kWp Artificial shading simulating commercial layout inter-row shading

covers 0.5% of the PV array

Comparative Case Study 4 – Germany

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Intr

od

uctio

n

SolarEdge Daily Energy gain vs. traditional inverter [%]

©2010 SolarEdge

Comparative Case Study 4 – Results

The distributed system produced 4% - 8% more energy than the traditional inverter on most days of the month

Distributed system production was lower on days with very low irradiance, due to sizable self consumption of the prototype DSP version of the unit, now replaced by an efficient ASIC

21©2010 SolarEdge

Layout Power optimizers + SE5000 compared to traditional inverter of a

leading brand 2 strings x 7 BP 3200N modules x 200w = 2.8kWp

Shading

Shade from a nearby electricity cable

Typical of residential sites

Module-level monitoring revealed shading pattern

©2010 SolarEdge

Comparative Case Study 5 – Spain

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Traditional [kWh]

SolarEdge [kWh]

Weekly Energy Gain [%]

Accumulated Energy comparisons shows the distributed system consistently produces 4% more energy than the traditional inverter

Ener

gy G

ain

in [

%]

©2010 SolarEdge

Comparative Case Study 5 – Results

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Inverters Power optimziers + SE6000 compared to two traditional 3kw inverters 4 strings x 10 Isofoton IS-150P modules x 150w = 6 kWp

Inter-row shading

Shading Inter-row shading Typical of commercial roof

with dense installations Modules are shaded for

2-3 hours every morning

Comparative Case Study 6 - Spain

©2010 SolarEdge

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On sunny days the distributed system produced up to 14% more energy due to intensified partial shading

On very cloudy days the distributed system produced 2% – 3% more energy. Clouds and low irradiance cast diffuse light with little or no partial shading.

©2010 SolarEdge

Comparative Case Study 6 - Results

The distributed system produced 4.5% more energy on average than the traditional inverter.

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whenhowwhat

whowhere

why

whenhowwhat

whowhere

why

Questions

Questions!

©2010 SolarEdge

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Thank you

Email:Twitter:Blog:

John.berdner@solaredge.com

www.twitter.com/SolarEdgePVwww.solaredge.com/blog

John Berdner, General Manager North America

©2010 SolarEdge

Website:www.solaredge.com