On-demand obstacle lighting for wind turbines

Dipl.-Ing.(FH) Thomas HerrholzENERTRAG Systemtechnik GmbHDauerthal (Germany)

Paris, 05.07.2011

ENERTRAG Systemtechnik

ENERTRAG AGis a European Independent Power Producer specialized in sustainable energy.440 turbines erectedApprox. 1000 turbines in operation or service

ENERTRAG Systemtechnik GmbHSupplier of obstacle lights for wind turbinesSpecialized on controlled low-emission LED-lightsMember of Bundesverband Windenergie e.V. (BWE)Member of speakers group in BWE-workgroup „Obstacle lights“Vice speaker of „Manufacturer and Suppliers“ advisory council in BWE

Outline

1. Wind turbines, aviation lights and acceptance

2. Technologies for detection

3. Legal framework (Germany)

4. Example for primary radar system (Nadrensee)

Outline

Wind turbines, aviation lights and acceptance

Wind turbines and aviation lights

Germany: ”General administrative regulation for the marking und lighting of obstacles to air navigation”, 24th April 2007:

Part 2, Section 1, 3.1:

Obstacles to air navigation shallbe marked and / or lighted

...b) outside the vicinity of aerodromes...outside towns and other densely populated

areas if the highest point of the structureexceeds a height of 100 m above groundor water surface

-> Typical turbine height is > 100 m above ground -> Similar regulations in most countries worldwide (100 – 150 m)-> marking of turbines causes acceptance problems

Aviation lights and acceptance

Study „Acceptance and environmentaltolerance of avoation marking on wind turbines“

PD Dr. Gundula Hübner & Dr. Johannes Pohl, Martin-Luther-Universität Halle-Wittenberg

April 2010

Download:http://www.bmu.de/erneuerbare_energien/downloads/doc/46048.php

Acceptance study - Outcome

GERMAN:„Aus Sicht des Anwohnerschutzes sowie der allgemeinen Akzeptanz der Windenergienutzung und im Hinblick auf den angestrebten Ausbaus der Windenergienutzung ist vordringlich eine bedarfsgerechte Befeuerung bei gegebener Flugsicherheit zu empfehlen.“

TRANSLATION:„Viewing from the point of resident protection and acceptance in general, with a view to the aimed developmentof wind energy usage, on-demand lighting with givenaviation safety is highlyrecommended“

HiWUS

HiWUS: Entwicklung eines Hindernisbefeuerungskonzeptes zur Minimierung der Lichtemission an On- und Offshore-Windenergieparks und -anlagen unter besonderer Berücksichtigung der Vereinbarkeit der Aspekte Umweltverträglichkeit sowie Sicherheit des Luft-und Seeverkehrs

(Development of a aviation light concept to minimize light emission from onshore and offshore wind energy projects with special condideration in compatibility of environment, aviation safety and maritime safety)

•German study 2007/2008•Phase 3.2: Field test Transponder•Phase 3.3: Field test primary radar•Definition of technical feasibility

Outline

Technologies for detection

Technology: Primary Radar

•Transmission of electromagnetic pulse into airspace•Reflection of pulse will be processed•Distance and direction of target is measured•Modern systems will also measure height and speed of target•Already used for windfarm (Canada, Sweden)•Field test Nadrensee

Advantages:•Independent from aircraft eqipment•Accurate position information•Day and Night operation•Technology available and tested

Disadvantages:•Line-of-sight needed (disturbance from WTG)•Cost intensive radar equipment•Use of frequency bands needs coordination

Picture: ENERTRAG

Technology: Secondary Radar (Transponder)

•Use of transponder•Transponder originally used for TCAS: Traffic Collision Avoidance System•Radio communication between aircraft and obstacle•Transponder sends Position, height, speed (dependend from protocol)•Also used by military and civil Air Traffic Control, esp. in high frequented air spaces•Field Test Wiemersdorf

Advantages:•Low-cost receivers•High range•No line-of-sight needed

Disadvantages:•Dependent from aircraft eqipment•Transponder not mandatory for all air spaces•Actually foreseen only for night operation

Picture: Enercon

Technology: Passive Radar

•Usage of bistatic effects•Reflections from existing transmitters at aircrafts received and processed•Transmitters can be: GSM, UMTS, DVB-T, FM•Intensive signal processing•Developed for military applications (temporary monitoring)•New technology

Advantages:•No active transmitters•Transmitter cost saved•No frequency coordination

Disadvantages:•Low signal strenght at receiver•Dependent from local transmitters and their proper function

Picture: Thales

Technology Summary

unknownNoneField test in Germany

Canada, SwedenField test in Germany

International usewith windfarms

misc.EnerconLanthanTSS

ENERTRAG/OCASKnowndevelopers

not neededpartially neededneededFrequency coordination

Long termMedium termShort termTime to market

not yet availablemandatory use and possible failure of transponders identifiedas a problem

no problems identifiedOperative Evaluation

unknownlowhighCost

Passive RadarSecondary RadarPrimary RadarTechnology

Outline

Legal framework (Germany)

On-demand lighting is not described in „Allgemeinen Verwaltungsvorschrift zur Kennzeichnung von Luftfahrthindernisse (AVV)“. Activation and deactivation is onlydescribed by the use of photocells.

Exceptions are possible with agreement fromBMVBS (Federal ministry of transport):

„26 Exceptional permission (no official translation):With acceptance of BMVBS regional aviation authorities can depart fromthese regulations if there is a reasonable explainatory statement.“

-> The regional aviation authority is responsible for the permission but needsacceptance from federal ministry of transport.

In the long term, AVV should be updated with description of on-demand obstaclelighting.

15www.ENERTRAG.com

Legal framework (Germany)

Outline

Example for primary radar system (Nadrensee)

Windfarm Nadrensee

Windfarm Nadrensee

ENERTRAG wind farm solution:• Radar installation on towers at wind farm periphery line• 220 – 240 ° coverage per radar• Aircrafts outside windfarm are detected• Height and distance depending warning• All lights switched on if warning is needed or system

failure occurs• 30s warning time before potential impact (adjustable)

Windfarm Nadrensee

Radar Radar unitunit

Power Power unitunit

Strobelight MasterStrobelight Master

Strobelight SlaveStrobelight Slave

supplysupply an an datadata connectionconnection

relayrelay interfaceinterfaceradarradar <> <> strobelightsstrobelights

EthernetEthernetStrobelight SlaveStrobelight Slave

Strobelight SlaveStrobelight Slave

Windfarm Nadrensee

•Installation in February 2009•Demonstration 24th Feb. 2010•13 WTG Vestas V90 105/125 m hub height•3 radars installed at 40m•“W, red” aviation lights EST100•Aviation light control network used•No permission for permanent operation received yet•Temporary permissions for test flights•Test of brackets, absorbers, radars•Adjustment of data connections•Testing on fail-safe operation•Test reports generated

-> Solution is technically ready for commercial installations-> Frequency coordination not finished yet-> Contracts for first installations in Germany are already closed

Windfarm Nadrensee

Examples from test reports:

Helicopter GPS tracks vs. Radar tracks

Top view

Side view

Warning zones:Red: physical obstacleOrange: safety marginYellow: ”May warn” zone, tolerance band

Thank you!

Dipl.-Ing. (FH) Thomas HerrholzGeschäftsführer COOENERTRAG Systemtechnik GmbHGut Dauerthal, D-17291 DauerthalPhone: +49 (0) 39854 6459-350thomas.herrholz@enertrag.comwww.enertrag.com