Contenu connexe Similaire à Maximum Energy Case Studies - EUPVSEC (20) Plus de SolarEdge Technologies (10) Maximum Energy Case Studies - EUPVSEC1. Field Results of Energy Maximizing
Distributed DC Topology –
Residential & Commercial Installations
John Berdner, SolarEdge
General Manager for North America
8. September, 2010
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2. Energy Loss Factors in Traditional PV Systems
System Energy Loss Design Energy Loss
Module mismatch Limited roof utilization due
to design constraints
Partial shading
Undervoltage/Overvoltage Indirect Energy Loss
Dynamic weather MPPT loss No module level monitoring
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3. SolarEdge System Overview
Module level optimization Module level monitoring
Fixed voltage - ideal installation Enhanced safety solution
Power Optimizer
Inverter
Monitoring Server Internet
Monitoring Portal
©2011 SolarEdge 3
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
250/300/400W 350W Thin Film 250/350W Module
Module Add-on Module Add-on Embedded
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©2010 SolarEdge
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 5
7. 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
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 7
8. Roof Utilization Case Study – Results
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)
280w 280w
West East
210w 210w
West East 280w 280w
East West
210w 210w
East West
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©2010 SolarEdge
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 9
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.
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©2010 SolarEdge
11. Comparative Case Study 1 – Unshaded
Under unshaded conditions distributed system produced
2.3% - 6.4% more energy than the traditional inverters
Energy Production 06-15 July 2010
60.00
50.00
Power Optimizers
40.00
kWh
30.00
+ SE5000
20.00
10.00
0.00
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©2010 SolarEdge
12. Comparative Case Study 1 – Shaded
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
SolarEdge Inverter A
Distributed
System
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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%)
Shaded Unshaded
6.00
5.65
5.43
5.00 5.20 5.21 5.27
4.00
Power Optimizers
kWh
3.00
2.00
+ SE5000
1.00
0.00
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* Inverter B was disconnected due to a technical issue during this test
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
Unshaded
reference
Shaded
SE5000
Shaded
traditional 14
©2010 SolarEdge
15. 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)
14 70
Shaded Unshaded Shaded
12 60
63.12
58.96
Daily energy, kWh
10 50
Total energy, kWh
8 40 45.25
6 30
4 20
2 10
0 0
1 2 3
Power Optimizers + SE5000
Traditional Inverter 15
©2010 SolarEdge
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
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©2010 SolarEdge
17. Comparative Case Study 3 - Results
The distributed system produced 1.65% more energy than the traditional
inverter
On days with dynamic weather conditions, distributed module-level MPPT
recovers energy otherwise lost due to delayed MPPT process
Power Module-level MPPT energy
Power Optimizers + SE5000
gain on that day: +2.9%
Traditional Inverter
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©2010 SolarEdge
18. The Impact of Dynamic Weather Conditions
As shown in comparative case study 3, moving clouds induce rapid
fluctuations in irradiance level
Centralized inverters are Sep 2nd 2010
more limited in their ability
to track changes in Imp
as fast as they occur,
compared to module-level
MPP trackers
10:00 – 11:00
±3kW fluctuations exhibited
for a 5kW inverter in the
span of minutes
©2010 SolarEdge
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19. Comparative Case Study 4 – Germany
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
©2010 SolarEdge
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20. 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
SolarEdge Daily Energy gain
vs. traditional inverter [%]
Introduction
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©2010 SolarEdge
21. Comparative Case Study 5 – Spain
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
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©2010 SolarEdge
22. Comparative Case Study 5 – Results
Accumulated Energy comparisons shows the distributed system
consistently produces 4% more energy than the traditional inverter
Traditional [kWh]
SolarEdge [kWh]
Energy Gain in [%]
Weekly Energy
Gain [%]
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©2010 SolarEdge
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
Shading
Inter-row
Inter-row shading shading
Typical of commercial roof
with dense installations
Modules are shaded for
2-3 hours every morning
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©2010 SolarEdge
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.
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©2010 SolarEdge
25. Questions
how what where
when why
how
Questions!
what where
who
when why who
©2010 SolarEdge
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26. Thank you
John Berdner, General Manager North America
Website:
Email: John.berdner@solaredge.com www.solaredge.com
Twitter: www.twitter.com/SolarEdgePV
Blog: www.solaredge.com/blog
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©2010 SolarEdge