The document discusses the advantages of SolarEdge's distributed DC topology using power optimizers, highlighting reduced energy loss due to features like per-module maximum power point tracking (MPPT) and module-level monitoring. Case studies from various regions demonstrate that distributed systems outperform traditional inverters, especially in shaded conditions, providing higher energy production. Overall, the technology enables better roof utilization and greater energy efficiency across residential and commercial installations.

1. 1
Field Results of Energy Maximizing
Distributed DC Topology –
Residential & Commercial Installations
John Berdner, SolarEdge
General Manager for North America
8. September, 2010

2. 2
Energy Loss Factors in Traditional PV Systems
System Energy Loss
 Module mismatch
 Partial shading
 Undervoltage/Overvoltage
 Dynamic weather MPPT loss
Design Energy Loss
 Limited roof utilization due
Indirect Energy Loss
 No module level monitoring
©2010 SolarEdge
to design constraints

3. 3
SolarEdge System Overview
Power Optimizer
Inverter
Monitoring Portal
 Module level optimization
 Fixed voltage - ideal installation
 Module level monitoring
 Enhanced safety solution
Monitoring Server Internet
©2011 SolarEdge

4. 4
SolarEdge Distributed Technology
 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
©2010 SolarEdge
250/300/400W
Module Add-on
250/350W Module
Embedded
350W Thin Film
Module Add-on

5. 5
Fixed String Voltage - Enabler
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
©2010 SolarEdge

6. 6
Field Trials and Results
©2010 SolarEdge

7.  Optimal roof space utilization enabled a 15kW residential installation
 Four facets covered
 Unmatched modules in each string were necessary:
 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
7
Roof Utilization Case Study – Israel
 Different module sizes (and rating)
 Different tilt and azimuth
©2010 SolarEdge

8. 8
Roof Utilization Case Study – Results
 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)
280w
East
210w
East
280w
West
210w
West
 Module-level monitoring reveals:
280w
West
210w
West
280w
East
210w
East
©2010 SolarEdge

9. 9
Comparative Energy Case Study Methodology
 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
Power
Optimizer
Power
Optimizer
Power
Optimizer
Power
Optimizer
Traditional system ©2010 SolarEdge Distributed system

10. 10
Comparative Case Study 1 - Italy
 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.
©2010 SolarEdge

11. 11
Comparative Case Study 1 – Unshaded
 Under unshaded conditions distributed system produced
2.3% - 6.4% more energy than the traditional inverters
60.00
50.00
40.00
30.00
20.00
10.00
0.00
kWh
Energy Production 06-15 July 2010
©2010 SolarEdge
Power Optimizers
+ SE5000

12. Comparative Case Study 1 – Shaded
 The best performing inverter of three other un-shaded traditional
12
 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
inverters was used as a reference
SolarEdge
Distributed
System
©2010 SolarEdge
Inverter A

13. 13
Comparative Case Study 1 – Shaded (Cont.)
 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
5.43
5.20 5.21 5.27
5.65
6.00
5.00
4.00
3.00
2.00
1.00
0.00
kWh
Shaded Unshaded
Power Optimizers
+ SE5000
* Inverter B was disconnected due to a technical issue during this test

14. 14
Comparative Case Study 2 – Czech Republic
 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
©2010 SolarEdge
Unshaded
reference
Shaded
SE5000
Shaded
traditional

15. 15
 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)
Shaded Unshaded Shaded
63.12
58.96
45.25
Comparative Case Study 2 – Results
70
60
50
40
30
20
10
0
1 2 3
14
12
10
8
6
4
2
0
Power Optimizers + SE5000
Traditional Inverter
Daily energy, kWh
Total energy, kWh
©2010 SolarEdge

16. 16
Comparative Case Study 3 - Germany
 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

17. Comparative Case Study 3 - Results
 The distributed system produced 1.65% more energy than the traditional
17
inverter
 On days with dynamic weather conditions, distributed module-level MPPT
recovers 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

18. The Impact of Dynamic Weather Conditions
 As shown in comparative case study 3, moving clouds induce rapid
18
fluctuations 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
±3kW fluctuations exhibited
for a 5kW inverter in the
span of minutes
10:00 – 11:00
Sep 2nd 2010

19. 19
Comparative Case Study 4 – Germany
 Power optimizers + SE5000 compared to traditional 5kw inverter
©2010 SolarEdge
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

20. 20
Comparative Case Study 4 – Results
Introduction
 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
SolarEdge Daily Energy gain
vs. traditional inverter [%]
©2010 SolarEdge

21. Comparative Case Study 5 – Spain
Layout
 Power optimizers + SE5000 compared to traditional inverter of a
©2010 SolarEdge 21
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

22. Traditional [kWh]
SolarEdge [kWh]
Weekly Energy
Gain [%]
22
Comparative Case Study 5 – Results
 Accumulated Energy comparisons shows the distributed system
consistently produces 4% more energy than the traditional inverter
Energy Gain in [%]
©2010 SolarEdge

23. 23
Comparative Case Study 6 - Spain
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
©2010 SolarEdge

24. 24
Comparative Case Study 6 - Results
 The distributed system produced 4.5% more energy on average
than the traditional inverter.
 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

25. howwhat who where
howwhat who where
25
when
why
when
why
Questions
Questions!
©2010 SolarEdge

26. 26
Thank you
John Berdner, General Manager North America
Email:
Twitter:
Blog:
John.berdner@solaredge.com
www.twitter.com/SolarEdgePV
www.solaredge.com/blog
©2010 SolarEdge
Website:
www.solaredge.com