Beispiel-Pr

EXPERIENCES WITH CABLE-BASED TRACKING 

SYSTEM AND PROGRESS TOWARDS TWO-AXIS 

LARGE SCALE SOLAR WINGS SYSTEM 

Zurich University 

of Applied Sciences 

May 2008; Prototype 4kW Dec 2008; 1. Solar Wings Park 650kW; 1-axis Oct 2009; 2-axis; 70kW 

Franz Baumgartner Prof. ,ZHAW University Appl. Sci. Zurich; Switzerland; https://home.zhaw.ch/~bauf/ 

Arthur Büchel CEO, Solar Wings AG, LI- Ruggell, Liechtenstein; info@solar-wings.li 

Roland Bartholet CEO, BMF-AG, Flums, Switzerland; www.bmf-ag.ch 

1

Outline: Progress Solar Wings 

• Advantage of tracking 

• Advantage of cable based Solar Wings systems 

• Realization of 650kW Solar Wings Prototype 

• Performance of 650kW Prototype 

• 2-axis tracking: Realization in Nov 2009 

• Outlook: low concentration 



Franz Baumgartner, EUPVSEC, 2009-09-22; www.engineering.zhaw.ch/en/ 2

Basic principles of tracking and concentration 

www.lorentz.de 

A. Büchel, F. Baumgartner et. al., Solar Wings FL 




Gain in Solarirradiance 

Solar Tracking + Concentration 

typical clear day sky condition 

tracking 

tracking 

+ 

mirror 

fixed 

installation 

tracking 




Photovoltaic MW Parks and Tracking 

Photovoltaic Parks 

Growth Segment in Germany, Southern Europe, 

Southern US, Middle East 

Various types of installations 

• Fixed installations 100% 

• Tracking solutions (1 axis) ~115 to 130% 



117% N-S axis, GCR 28%, 32°N; N-S axis ~3% higher yield 

compared to E-W axis; D. Weinstock, J. Appelbaum 2009; JSEE 

• Tracking solutions (2 axis) ~120 to 135% 

• Theoretical limit (2 axis) 141% 

[RC. Neville, Solar Energy 1978] 

Energy Yield 


Solar parks and tracking systems 

in the multi-MW-class 

Market leader 

Sunpower T20 

M. Riello; Intersolar 

2008-06-11, Munich 

www.sunpower.com 



New comer: PV-Tracking from Switzerland, 

Solar Wings 2008; F. Baumgartner; Euro PV Conf 2008 


„Solar Wings“ Concept: 

Benefits: 

• Robust design 



• Optimal energy yield 

• Double use of land 

• Low maintenance cost 

one motor each 100kW 

• Excellent mat. Utilization 

• Support of BOS comp. 


Many Years Experience with Cabels 

Solar Wings Project Partner BMF 



Engineering and construction of more than 200 cable systems, skilifts worldwide; www.bmf-ag.ch 


„Solar Wings“ Prototype: 2008 May 



Prototype realized: 

• Extensive study of 

wind load, snow/ice 

completed, findings 

implemented in 

horizontal prototype 

• Reliability on prototype 

confirmed 

• System operational 

tests 


First Solar Wings Project: 

one axis tracker: 650kW 

• Location: Germany, Waldshut 

Customer: Lonza AG, Switzerland 

• Requirements from the site: 

Waste disposal site; 

waterproof layer below 0.8 meter; 

land subsidence expected 

• Technical Features 

Solar Wings 1 axis tracking with 

650kW PV Modules from Sunways; 

21 Sunways Inverters 30kW 

• Connected to the grid in Dec 2008 

300m 

40m 

19m / 23° slope 




Construction Phase 1: Foundation 



646.76kWp Lonza Solarpark in Waldshut Germany; Ownership Gewerbepark Hochrhein and Stadtwerke Waldshut-Tiengen 

Mounting and Construction of Solar Wings Tracking Syst. by Bartholet AG, www.bmf-ag.ch; PV Modules and Inverters Sunways.de; 


Construction Phase 2: Cabel and Module Beam 






Phase 3: Tracking cables / drive 

AC Motor 1kW 

tracks 

200kWp PV-power Tracking cable 

Tracking cable 

Supporting cable 

Tracking cable 






Sensors of the Lonza-Solarpark 

• Wind sensor 

• Snow sensor 

• Irradiance Sensors 

tracked 

fix 






Solar Wings System Features 

Features: One-Axis Tracking : First Solar Wings Plant / Lonza-Solarpark, Waldshut 

• + 17% Energy yield tilt axis 23°; Range of rotation angle: +/-45° 

• 2 Linear drive: to track each 200kW modules 

• Industrial SPC Control Unit; time controlled Sensors: Wind, Temp , Snow, Force 

• At high wind loads the tracker moves in the low wind resistance position 

• BOS (Inverter, DC/AC cabeling) integrated into the support system 




1-axis Solar Wings Tracking System 647kW 

300m 

GRC=0.25 

2.5m 

PV Field North/West 


Modules and Inverters from Sunways.de; ( 8 x 60 x 6 ploy Si modules SM210U; 21 pieces of 30kW Inverters PK30) 



String: 

3x8=24 

SM210U 


2009-09-09: Solartracking: +23% kWh/kWp 

+ 

Data from Sunways AG; Independent monitoring performed by ISE Freiburg 

+ 



1-axis tracking 

+23% kWh/kWp 

relative to 

fixed installation 

at clear sky cond. 


Energy Production Solar Wings 

1. year kWh/kWp 

Performance Ratio: 90% to 95% 

200 

150 

100 

50 

0 

Lonza Solarpark 

Jan 

09 

Feb 

09 

Mrz 

09 

Apr 

09 

Mai 

09 

Jun 

09 

Jul 

09 



Franz Baumgartner, EUPVSEC, 2009-09-22; www.engineering.zhaw.ch/en/ 18 

Aug 

09 

Sep 

09 

Status 2009-09-14: 1090kWh/kWp produced 

Wh/Wp fix, Konstanz 

Wh/Wp tracking, Waldshut 

Okt 

09 

Nov 

09 

Dez 

09

Next steps 2009: 

Solar Wings 2 Axis Tracking 

North/South Tracking 

Winter/Summer 

East/West Tracking 

Morning/Evening 

(Patent filed) 

Design Concept: 



• Revolving End Foundations 

and intermediate Supports 

• Up to 1000m bearing cables, 

intermediate foundations 

approx. 40 to 100 meters 

• Standard three-phase electrical 

drives to power both trackers: 

East/West and North/South 

• Gain in Energy Yield up to +35% 

at Southern Europe latitudes 


2-axis Solar Wings Prototype 

6m 

Power: 70kWp 

Heigth above Ground: 6m 

Location: 

Flums Switzerland 

Double USEAGE 

On top of the open-air 

storage facility 

of the Flumroc AG 

Installation 2009 




2-axis Solar Wings Prototype 

Power: 70kWp 

Heigth above Ground: 6m 

Location: 

Flums Switzerland 

Double USEAGE 

On top of the open-air 

storage facility 

of the Flumroc AG 

Installation 2009 




Outlook: 

How to get more from the sun? 

• One axis tracking: 

Solar Wings 

• Two axis tracking: 

Tracking Wings 

• Optical concentration: 

Power Wings 

using planar mirrors low 

concentration 



Annual 

Energy gain: 

+20 to 25% 

+25 to 35% 

>50% 


Experimental Test Setup 

Power Wings One Planar Mirrow 

Dish Experimental Test Setup 

• PV Mini-Module 

i.e. two 5 inch cr. Silicon cells 

• Temperature sensor PT100 

integrated in the laminate 

• Planar Mirror: 

flat Aluminium reflector 



• Each of the 3 axis are controlled by 

an individual stepper-motor 

Measurement Results performed at University of Applied Science Zürich ZHAW, Winterthur 2008 


Measurement Results 

Power Wings One Planar Mirror 

tracking 

mirror 

fixed 

P dir /P global 

50% 80% 90% 80% 50% 

PV Mirror 

Results on a clear day: 



tracking +mirror V3 163% 

tracking +mirror V4 162% 

tracking no mirror 132% 

fixed installation 100% 

Measurement Results performed at University of Applied Science Zürich ZHAW, Winterthur 080909 


Power Wings Tracking / Mirrows 

C=2 

1. Mirror 2. Mirror PV Cell 



Experimental Setup at ZHAW 2008/09 


Investment and Savings 

Investment 

180% 

160% 

140% 

120% 

100% 

80% 

60% 

40% 

20% 

0% 

Fixed 

Tracking 

Power 

Wings 

0% 

-5% 

-10% 

-15% 

-20% 

-25% 

-30% 

-35% 

-40% 

-45% 

-50% 



Franz Baumgartner, EUPVSEC, 2009-09-22; www.engineering.zhaw.ch/en/ 26 

Savings: Invest / kWh 

Savings Invest/En. Yield 

Mounting 

Other 

DC/AC 

Module 

Savings Invest

Status of cable base Solar Wings 

• Cables successfully used to mount tracked 

PV modules; less amount of used steel: 

• Solar Wings prototype realised and tested 

• Dec 08: First Solar Wings one axis project 

650kW on the grid 

• Performance >1300kWh/kWp, PR=0.92 

• Oct 09: Two axis prototype realized, First 

Park in 2009 



• Merit of low optical concentration confirmed 

tests on the kW level in 2009 mirror PV 


Thank You for your Attention 

Download reprints: 

https://home.zhaw.ch/~bauf/

Beispiel-Pr

Create successful ePaper yourself

Delete template?

Save as template?