natural power zephir brochure ecopy
DESCRIPTION
anemomether, winds, natural powerTRANSCRIPT
lidar wind profiler for reliable, accurate, bankable wind data up to 200m from ground level
ZephIR® laser anemometer
clever ™
natural power
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depl
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measure wind with ZephIR®We PIoNeeRed the use of LIdAR IN the WINd INdustRy some eIght yeARs
Ago. WIth moRe thAN 200 ZephIR dePLoymeNts gLobALLy We RemAIN the
mARket LeAdeR.
ZephIR has successfully operated through Canadian winters and Australian summers. Customers
have financed projects using ZephIR data. Banks’ Engineers recommend ZephIR onshore and
offshore to both complement and replace traditional masts. This is how we do it:
• 10m to 200m wind profile - speed, direction, turbulence
• speed accuracy* < 0.5%
• direction accuracy* < 0.5°
• 50 data points per second
• - 25°C to + 40°C operation (extendable operating range)
• 100W average power draw**
• + 5 years experience in the field
• Industry approved calibration
• Accepted by banks’ engineers
• one-man portable pods
So what can we do to reduce your project risk and uncertainty?
measure the wind up to 200 metres from ground level ......... in the time it takes to read this sentence
* as measured against a calibrated moving target
** in standard dry climates (-13°C to +25°C)
ZephIR has been used on more than
200 deployments and has operated in
23 countries worldwide
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ZephIR APPLICAtIoNsIN the WINd INdustRy
the ACCuRAte PRedICtIoN of eNeRgy yIeLds Is fuNdAmeNtAL to the
suCCess of WINd fARm PRojeCts. yIeLd PRedICtIoN ACCuRACy INCReAses
by CoLLeCtINg hIgh quALIty WINd dAtA fRom NumeRous PoINts
thRoughout A WINd fARm ANd At APPRoPRIAte heIghts INCLudINg the
fuLL RotoR sWeeP. thIs deNsIty of dAtA CoLLeCtIoN Is dIffICuLt ANd
exPeNsIve to AChIeve WIth tRAdItIoNAL ANemometRy mAsts ALoNe.
Based at ground level, ZephIR provides complete wind resource measurement including horizontal
and vertical wind speed, wind direction and turbulence at any height up to 200 metres without
the need for a mast. ZephIR requires no planning permits and removes the need to work at height,
mitigating associated health & safety issues.
The portability of ZephIR and ease of deployment makes high density data collection a reality with
50 measurements per height per second, both horizontally and vertically across the extent of your
site. ZephIR is used in four phases of a project:
• site prospecting, assessment and turbine micro-siting
• Wind flow model verification
• Power curve assessment
• Permanent wind farm anemometry and operational wind farm analysis
ZephIR has been independently tested and validated by respected parties in the wind industry.
“ZephIR is approved to be added to the ReRL suite of wind speed measurement devices“
- University of Massachusetts (UMASS)
“during the offshore assessment campaign ZephIR came up with a remarkable data availability, clearly being better than the demanded 95%... ZephIR should now be thought of as a powerful tool to aid in the understanding of flow conditions on sites being investigated“
- Germanischer Lloyd WINDTEST
“the ZephIR technology has provided Naikun with continual wind resource measurement in a very challenging offshore environment. Its reliability and performance has been close to 100 per cent and is a valuable asset in the development of the Naikun offshore wind project in hecate strait near haida gwaii (the queen Charlotte Islands)”
- NaiKun Wind Development Inc.
“We evaluated ZephIR’s performance next to a 100m mast in complex terrain and witnessed extremely high correlations against traditional meteorology, at all heights”
- Center for Renewable Energy Sources (CRES)
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the PRINCIPLes of LIdAR
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25 minutes set-up 10 metres (33 feet) allowing for correlations to short masts or historic wind data. Low measurements are particularly important offshore when the system is on a raised platform or when an accurate onshore shear measurement is required.
200 metres (656 feet) allowing measurements across the full wind turbine rotor diameter including hub height and tip height measurements.
5 user defined heights configured using the simple ZephIR Waltz™ software supplied with every system.
dR mIChAeL hARRIs, seNIoR sCIeNtIst At NAtuRAL PoWeR,
hAs sPeNt oveR A deCAde WoRkINg IN the fIeLd of LIdAR
ReseARCh ANd desIgN. mIChAeL WAs fuNdAmeNtAL IN the
desIgN CoNCePt of ZephIR At oNe of euRoPe’s LeAdINg
ReseARCh ANd deveLoPmeNt INstItutes. beLoW, he
outLINes the PRINCIPLes of LIdAR.
“An eye-safe infrared beam illuminates natural aerosols in the atmosphere
(such as dust, pollen and water droplets) and a small fraction of the light is
back scattered into a receiver. Motion of the target particles along the beam direction leads to a
change in the light’s frequency through Doppler shift which is then accurately measured.
A conical scan pattern is used to move the
beam and intercept the wind at different angles,
building up a series of measurements around a
disc of air from which the wind speed vector is
obtained.
ZephIR obtains each measurement in just 20
milliseconds and one second of data can be
used to derive the horizontal and vertical wind speed components and wind direction. This can
then be repeated from 10 metres up to a height of 200 metres, at five or more user-defined
heights by focussing the transmitted beam.”
Michael is invited to present lidar papers and tuition sessions within a wide range of organisations
across Europe and North America. He has conducted fundamental optics research at JILA
(Boulder, Colorado) and the University of Essex.2 metres (6 foot 6 inches) ground level wind measurements plus temperature, barometric pressure and humidity.
INdePeNdeNt CoRReLAtIoNs
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Risø evaluation of ZephIR at høvsøre, 2008
ZephIR is compared to the fixed anemometry at Risø’s Høvsøre 116m met mast. Ten minute average wind speeds are
collected over a 10 week period at 4 heights. This recent study took place during the Spring of 2008.
germanischer Lloyd WINdtest evaluation of ZephIR offshore at fINo1 research platform, 2006
ZephIR is compared to the fixed anemometry over a six month period.
For the above campaign, the availability was recorded as:
• 100% for the overall system availability
• 99.6% for the overall data availability
ZephIR evaluated at Risø’s høvsøre test, 2009
ZephIR is compared to the fixed anemometry at Risø’s Høvsøre 116m met mast during a test campaign over Winter 2009.
y = 0.999xR² = 0.986
0
2
4
6
8
10
12
14
16
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20
0 2 4 6 8 10 12 14 16 18
Zeph
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ind
Spee
d 98
m
Mast Wind Speed 100m
ZephIR vs. cup @ 100m
y = 1.000xR² = 0.988
0
2
4
6
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10
12
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18
0 2 4 6 8 10 12 14 16 18
Zeph
IR W
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Spee
d 78
m (m
/s)
Mast Wind Speed 80m (m/s)
ZephIR vs. cup @ 80m
y = 0.999xR² = 0.992
0
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4
6
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18
0 2 4 6 8 10 12 14 16 18
Zeph
IR W
ind
Spee
d 58
m (m
/s)
Mast Wind Speed 60m (m/s)
ZephIR vs. cup @ 60m
y = 0.999xR² = 0.986
0
2
4
6
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10
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0 2 4 6 8 10 12 14 16
Zeph
IR W
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Spee
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m (m
/s)
Mast Wind Speed 40m (m/s)
ZephIR vs. cup @ 40m
The correlation graphs show the relationship between the wind speed readings from a cup and the corresponding wind
speed readings from the ZephIR. Data are plotted against each other and a line of best fit drawn. By forcing this line
of best fit through the origin its gradient, y, indicates the mean difference between the two readings. For example, a
gradient of 1.01 would indicate a difference of 1%. The R2 value gives an assessment of how well correlated the two
sets of values are. If the cup and the ZephIR always read identically then the R2 value will be 1, i.e. they are perfectly
correlated. At the other extreme, an R2 value of zero would indicate that the values bear no relationship to each other
whatsoever.
evaluation of ZephIR at a tall mast in North America, 2009
The identical ZephIR system tested above is also compared to the fixed anemometry at a 193m met mast during a test
campaign in Spring, 2009.
beNefIts of ZephIR LIdAR
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Not ALL LIdARs ARe the sAme. ZephIR Is desIgNed ARouNd veRy sImPLe,
Rugged ANd ReLIAbLe oPtICs, the heARt of WhICh Is A CoNtINuous WAve
(CW) LIdAR WhICh PRovIdes CLeAR AdvANtAges oveR otheR LIdAR systems
Sensitivity
ZephIR’s sensitivity remains constant at all heights ensuring high data availability in all conditions.
The emitted laser beam is focussed at each user configured height - the laser power does not
change at each height or with range and so the sensitivity does not degrade.
Sample rate
ZephIR measures 50 data points every second across a full 360 degree scan providing the high
sample rate advantageous in complex and fast changing air flows.
Accurate measurements
ZephIR provides highly accurate measurements from 200 metres down to just 10 metres from
ground level where wind shear typically changes more rapidly with height.
As height increases and wind shear changes less rapidly, ZephIR still provides highly accurate
measurements with a probe length of less than 8 metres @ 100 metres height. Similarly, the
optics are designed such that at 200 metres, ZephIR delivers excellent results as demonstrated on
the previous page.
ZephIR’s optical design ensures that at these crucial low heights, probe length (effective sample
length) can be as small as just 7 cm.
CLoud ReCogNItIoN ANd RemovAL
CLouds CAN be hIghLy sCAtteRINg objeCts WhICh PRovIde A sIgNAL thAt
Is meAsuRed by LIdARs. INCLusIoN of these sIgNALs IN PRoCessed dAtA
CouLd LeAd to AN oveRALL INCReAse IN the uNCeRtAINty of the WINd
sPeed meAsuRed.
heIght y (mean difference) R2 (correlation)totAL dAtA
PoINtsdAtA PoINts WIth CLoud
116m 0.990 0.986 2604 1098
100m 0.999 0.986 2603 1098
80m 1.000 0.988 2601 1094
60m 0.999 0.992 2597 1093
40m 0.999 0.986 2740 1192
ZephIR is able to recognise and remove this cloud signal using a patented cloud removal algorithm. This has been
extensively tested in a number of locations, and its effectiveness demonstrated by correlation analysis against calibrated
tall masts.
During the wind profile scan, background measurements are taken to quantify the specific cloud return and the cloud
effect is then removed from the processed data. In general, Lidars of various types of design will all have difficulty
measuring in very low cloud and fog scenarios; the light emitted from the Lidar simply doesn’t reach the height of
interest due to the density of the atmosphere. Whilst this atmospheric condition mostly occurs during low wind speed
periods, it is essential that these periods be identified. With ZephIR these particular conditions can be ‘seen’ and
automatically detected and filtered.
ZephIR can be configured so that the data output is automatically filtered for such conditions of reduced certainty, ready
to use wind data simply presented to you over the averaging period of your choice.
In order to demonstrate the accurate performance of ZephIR with cloud conditions the above results have been
measured. The data set below was taken during periods of both clear (~ 60%) and cloudy (~40%) skies. The number
of data points taken during cloud has been indicated (cloud was measured using a Ceilometer), demonstrating excellent
accuracy in extreme cloud conditions.
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INdustRy ACCePted vALIdAtIoN
ALL LIdAR systems Need to be suCCessfuLLy vALIdAted to AN INdustRy
ACCePted stANdARd befoRe CustomeRs CommeNCe dePLoymeNt.
bANks’ eNgINeeR gARRAd hAssAN hAve WoRked WIth us IN defININg
the PRINCIPLes of ouR CeRtIfICAtIoN PRoCess foR ALL NeW systems.
thIs PRovIdes the tRACeAbILIty WhICh Is A key eLemeNt of foRmAL
eNeRgy PRedICtIoN RePoRts used by the fINANCIAL CommuNIty. befoRe
shIPPINg, eACh ZephIR uNdeRgoes seveRAL stAges of RIgoRous CheCks.
these PRoCesses ARe RePeAted As PARt of the RoutINe mAINteNANCe
WheNeveR A uNIt RetuRNs to NAtuRAL PoWeR.
Velocity and Directional Accuracy
The velocity and directional accuracy are checked in the laboratory against a calibrated moving target, to an accuracy of better than 0.5%. The velocity calibration depends only on laser wavelength and scanner cone angle, so there is no risk of drift even over an extended period of operation.
Velocity resolution of ZephIR is very high and its accuracy is measured to be 0.003m/s against a calibrated moving belt target.
Focussing at HeightZephIR focus is calibrated at the factory and its range is set by a closed loop positioning system.
Calibrated Reference UnitEach ZephIR undergoes an outdoor test to measure wind speed side-by-side against a Reference Unit. The Reference Unit has been checked against a tall mast such as at Risø’s Høvsøre test site; this provides traceability to measurements. Risø are the National Laboratory for Sustainable Energy at the Technical University of Denmark - DTU.
The reference system is compared below to the fixed anemometry at the test site showing strong correlation and a
gradient close to 1:
A typical new ZephIR system is compared below to the reference system and again shows strong correlation and a
gradient close to 1:
sAfety & eNvIRoNmeNtAL CeRtIfICAtIoNs
LIdAR systems IN the WINd INdustRy must oPeRAte sAfeLy. ZephIR
hAs uNdeRgoNe RIgoRous sAfety testINg eNsuRINg ANy useR CAN
effeCtIveLy oPeRAte the system WIth mINImAL tRAININg ANd No sPeCIfIC
quALIfICAtIoNs oR CeRtIfICAtIoN IN LAseRs. We hAve suCCessfuLLy
AdheRed to euRoPeAN sAfety LAWs ANd kePt WIthIN the LoWest LeveL
of LAseR CLAssIfICAtIoN. As A Ce-mARked, CeRtIfIed CLAss 1 LAseR
system, ZephIR CAN be dePLoyed sAfeLy ANyWheRe, by ANy AbLe body.
Conformité Européenne - the CE markThe CE marking is a mandatory conformity mark on many products placed on the single market in the European Economic Area (EEA). The CE marking certifies that a product has met EU consumer safety, health and environmental requirements.
ZephIR is Ce compliant, certified by an independent compliance company who are fully ukAs accredited.
ZephIR achieved full safety compliance for electrical equipment and measurement, standard eN61010-1:2001.
ZephIR has achieved eN61326:1997 for emC emissions and susceptibility.
Environmental performanceWind projects are often sited in challenging conditions where equipment is exposed to the elements for extended periods of time.
ZephIR is constructed using a twin-skin Glass Reinforced Plastic (Polyvitro infusion composite) with a layer of Xtratherm Polysio (PIR) Foam. This method of fabrication has proved highly successful across the full and extensive operating temperature range which has been tested both in an environmental chamber and in the field during customer deployments.
ZephIR is IP65 rated for resistance to particle and water penetration. Deployments on offshore platforms have demonstrated the systems ability to withstand offshore conditions such as sea spray and salt corrosion for prolonged periods of time.
The tall, round design of ZephIR ensures snow does not build up during severe weather conditions. The top pod has a very small surface area and is angled to reduce the risk of snow gathering and prevent the laser beam being emitted.
Laser safetyThe operator of a laser system outdoors must comply with the international legislation on laser safety (IEC 60825-1) to ensure protection of workers and the general public. Higher class lasers (Class 3R, Class 3B, Class 4) are potentially hazardous and their use outdoors places a responsibility on the user to minimise any risks.
ZephIR has been independently certified as Class 1, the lowest laser category into which everyday devices such as CD players are placed and poses no hazard to operators.
The international standard defines Class 1 as: “lasers that are safe under reasonably foreseeable conditions of operation, including the use of optical instruments for intrabeam viewing”.
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system softWAReZephIR Waltz™ & ZephIR tempo™
ZephIR Is suPPLIed WIth PRoPRIety softWARe - WALtZ™ ANd temPo™ - thAt
PRovIdes A useR-fRIeNdLy INteRfACe to youR ZephIR vIA A PC.
ZephIR WaltzWaltz allows the user to access ZephIR remotely in realtime to configure heights, play data live and access system updates. The screen shot below shows just how simple it is to configure the five different heights between 10m and 200m from ground level.
The screen shot below is a view of the operational screen and highlights the data collected by ZephIR.
ZephIR TempoTempo allows for automated, scheduled data download at a set period. Customers with multiple units are able to automatically, quickly and consistently dial in to units and download all data since the last scheduled download.
dAtA doWNLoAd
oNCe dAtA hAs beeN doWNLoAded to youR ComPuteR It Is A sImPLe CLICk
to exPoRt It ALL IN to A .Csv fILe foRmAt foR ANALysIs, oR ImPoRt It
dIReCtLy IN to A PRogRAm suCh As WINdogRAPheR. dAtA Is PReseNted
IN A foRmAt CoNsIsteNt WIth tRAdItIoNAL ANemometRy, keePINg the
PRoCess sImPLe foR WINd eNgINeeRs.
Header DescriptionsReference; Each one second measurement has a reference associated with it. The reference starts at zero and increments with each reading.
timestamp; The time and date of the reading as anumerical format in seconds.
height (m); Current ZephIR measurement height.
horizontal velocity (m/s); Mean horizontal wind speed as measured by the ZephIR at the given height.
vertical velocity (m/s); Mean vertical wind speed as measured by the ZephIR at the given height.
Wind direction (degrees); Wind direction as measured by the ZephIR at the given height.
turbulence Intensity; Mean variation of individual point measurements from the mean wind speed. This is normalised by the horizontal wind speed.
min gust (m/s); Minimum one second wind speed measuredby the ZephIR in the ten minute average.
max gust (m/s); Maximum one second wind speed measured by the ZephIR in the ten minute average.
ZephIR bearing (degrees); Compass bearing of ZephIRNorth arrow.
met. speed; Horizontal wind speed as measured by themet. station.
Wind vane Reading (degrees); Wind direction as read by ZephIR met. mast
temperature (C); Ambient temperature measured by the MET station.
Pressure (hPa); Ambient pressure measured by the met. station.
humidity; Ambient humidity measured by the met. station.
status flags; Internal ZephIR status [Red/Amber/Green].
gPs data; GPS location data as set in the configuration.
battery status (v); External supply voltage if present, otherwise internal battery voltage.
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PoWeR soLutIoNs
ZephIR RequIRes A CoNstANt 100 WAtt suPPLy duRINg NoRmAL oPeRAtINg
CoNdItIoNs. WhILst mANAgINg A fLeet of ReNtAL systems We hAve
gAINed muCh exPeRIeNCe IN PRovIdINg Remote PoWeR.
ZephIR standard power requirementsTo ensure ZephIR only draws the power it needs during varying operating temperatures, the system is designed to automatically control heaters and fans as necessary. Details of the power requirements varying conditions are shown below.ZephIR is specified to operate between -25°C and +40°C. ZephIR has been laboratory tested within these ranges but operation outside of this range is possible. We have seen
in practice over several winter and summer seasons that operation is possible down to -40°C when an insulation jacket is used and up to +50°C at the other extreme. If ZephIR is exposed to temperatures below -10 degrees regularly it is recommended to use an insulating jacket. This reduces power draw and provides some protection from the elements.
CommuNICAtIoN oPtIoNs
Remote seNsINg devICes ARe dePLoyed WoRLdWIde ANd RequIRe fLexIbLe
CommuNICAtIoNs to seCuReLy ACCess dAtA dIReCtLy fRom youR desk
ACRoss A vARIety of NetWoRks.
EthernetEthernet is a global networking standard supporting high speed communications locally, or over distance. The ZephIR Ethernet port can be connected directly to a laptop or into Wifi, the Internet or a corporate network for direct communications with your office.
GSMThe most widely supported mobile phone protocol is GSM. It is used by over 3 billion people across more than 212 countries and territories. Each ZephIR comes with a built in GSM modem. This allows communication with the ZephIR through the telephone network using a modem. GPRS is also supported, allowing direct access from internet enabled machines and support for networks where GSM is not available.
IridiumFor ultimate flexibility, the Iridium satellite network provides truly global communications for your ZephIR. Simply connect the optional Iridium modem to get direct access to your device, pole to pole.
Satellite InternetWhere standard mobile infrastructure fails, satellite internet can be deployed. This method provides a high speed, dedicated link between the ZephIR and the internet using a satellite dish and can be used in locations with line-of-site to geo-synchronous satellites over the equator.
Communications Service PackageNatural Power are happy to offer a fully managed service package for your communications requirements. Please get in touch to find out more.
Data StorageZephIR writes all data to an integral, removable flash memory card. Customers are able to store 12 months of 3 second wind data on one card. This onboard storage offers a back-up should the regional communications network have any failures during the deployment.
Natural Power anemometry servicesWe are able to provide a fully managed anemometry service for your ZephIR deployments ensuring all wind data is downloaded, stored and delivered to you. Our wind engineers currently manage a portfolio of anemometry devices globally for project developers and utilities.
standard Climate(-13°C to +25°C)
Cold Climate(-25°C to -13°C)
hot Climate(+25°C to +40°C)
Standard draw 100W 110W* 100W
Heaters - 76W -
Fans - - 18W
totAL 100W 186W 118W
* in cold weather the standard draw increases from 100W to 110W due to heaters in the MET station drawing 10W
During extreme cold conditions where the batteries have been completely discharged higher power draw will occur. During wiper activation an additional 10W is required periodically. ZephIR has 12 - 24 hours reserve power provided by internal batteries.
INPUT VOLTAGE RANGE: 27.75v +/- 0.5v
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NAtuRAL PoWeR’s methodoLogy IN ComPLex teRRAIN
the stAte of the ARt IN the APPLICAtIoN of Remote seNsINg ANd Cfd
Complex wind farm sites present various challenges which can often limit the applicability of conventional wind resource and energy yield measurement assessment methods, due to the complexity of the flow physics at play and the spatial and temporal variations in the flow conditions.
The effects of this are varied; the typically steep slopes encountered on complex terrain sites often violate the assumptions on which linearised flow models are based, notably the assumption that topography is a perturbation to the horizontal flow, rather than a true 3-D effect. An off-horizontal flow can result in measurement errors with anemometry. Additionally, forestry cannot be accurately modelled using simple methods for a number of reasons. Regions with significant veer can complicate wake loss and wind prediction calculations. Finally, strong wind speed gradients make the energy yield very sensitive to the precise location of the measurement systems used.
Measuring and predicting wind flows in complex terrain requires a methodology that addresses the above challenges.
Natural Power has developed a best-practice methodology which combines several leading technologies to reduce and quantify wind resource and energy yield prediction uncertainties.
The Natural Power methodology uses a combination of high-density measurement campaigns alongside an advanced CFD flow model (VENTOS®). VENTOS® has been specifically and intensively validated for application on complex terrain and forested sites.
A map is produced showing the area of highest flow complexity in terms of turbulence, shear, inflow angle, veer and deviation from conventional flow modelling results. This identifies areas where flow modelling uncertainty is highest and informs where further measurement campaigns are best performed in order to deliver an optimised reduction in prediction uncertainty. Measurements are then performed at as many locations as deemed necessary, using a combination of conventional anemometry and ZephIR (a lidar wind profiler) as required to obtain an optimum balance between measurement density and increased certainty in the results.
These measured and modelled data sets are then fed into an overall analysis model, with the output of the process being a set of maps which describe the full set of flow variables across the site, validated by measurements. These variables include; inflow angle, veer, shear profile across the rotor disk, mean horizontal velocity and turbulence intensity. These variables not only serve as turbine micro-siting constraints and to provide an estimate of mean annual wind resource and energy production, but serve as an input to site classification and wind quality analyses, which are increasingly required for engaging with prospective turbine technology suppliers on complex terrain sites.
meAsuRINg tuRbuLeNCe
tuRbuLeNCe CAN mANIfest ItseLf As gusts, eddIes, ANd fLuCtuAtIoNs
IN WINd sPeed. It Is ImPoRtANt IN WINd eNeRgy APPLICAtIoNs to
ChARACteRIse the LeveLs of tuRbuLeNCe eNCouNteRed At A sPeCIfIC
sIte LoCAtIoN. A CommoNLy-used bAsIC meAsuRe of tuRbuLeNCe Is
tuRbuLeNCe INteNsIty (tI). ZePhIR AutomAtICALLy CALCuLAtes ANd Logs
the vALues of tI foR eACh 10-mINute meAsuRemeNt PeRIod.
ZephIR calculates the turbulence intensity (TI) that a conventional cup would have obtained at the same measurement height by analysing the variation in individual wind speed values during a 10-minute averaging period. This value of TI is automatically logged in the output data. The calculation takes into account the difference between point measurements obtained from a cup anemometer, and spatially-averaged lidar data where a volume is interrogated. ZephIR’s measurements of turbulence have been investigated in a number of independent studies against calibrated met masts in flat, offshore and complex terrain, and at different heights above ground*.
The plot below shows a comparison of standard deviation for 10-minute averaged horizontal wind speeds obtained by ZephIR and calibrated cup anemometer mounted on 80m meteorological mast. All sectors are included and no filtering has been performed. ZephIR was deployed 62m from the mast in flat terrain; the agreement between individual points is affected by the separation and differing probe volumes, an overall assessment of the site turbulance shows good agreement.
* “Investigation of turbulence measurements with a continuous wave, conically scanning lidar”, R Wagner, T Mikkelsen, M Courtney, Risø-R-1682(EN), March 2009
CAse study 1 : spainNational Renewable energy Centre (CeNeR)
the PuRPose of the CeNeR WINd eNeRgy dePARtmeNt Is to deveLoP
APPLIed ReseARCh ACtIvItIes ANd gIve teChNICAL AdvICe IN the fIeLd of
WINd eNeRgy, PRovIdINg A seRvICe foR ALL the seCtoR PLAyeRs, suCh
As deveLoPeRs, mANufACtuReRs, CeRtIfICAtIoN AuthoRItIes, fINANCIAL
INstItutIoNs, useRs, AssoCIAtIoNs ANd AdmINIstRAtIve bodIes, both
At home ANd AbRoAd. the AIm, IN shoRt, Is to ImPRove the effICIeNCy
ANd theRefoRe the ComPetItIveNess of AN evoLvINg seCtoR. IN thIs
seNse, the CeNeR WINd eNeRgy dePARtmeNt Is WoRkINg oN dIffeReNt
ReseARCh PRojeCts, oN Its oWN INItIAtIve ANd IN CooPeRAtIoN WIth
teChNoLogICAL CeNtRes, INstItutIoNs ANd ComPANIes.
“During 2009 and 2010 the Wind energy Department of CENER is
developing an experimental test site in complex terrain in the north
of Spain, for the testing of multi-megawatt wind turbines, up to 120m
hub height.
ZephIR is an integrated tool of this facility, which complements the
measurements provided by the meteorological masts. In particular,
ZephIR allows measuring the wind conditions up to heights greater
than hub height. Moreover, the option for mobility that the lidar
provides, allow us to measure upwind or downwind conditions
when required. ZephIR has been integrated in the experimental
site calibration, in order to allow for future use of the lidar as a
complement to standard-compliant tests and research activities.
CENER’s previous experience with ZephIR lidar includes various
measurement campaigns, mainly in complex terrain. Most of our
activities have been carried out under the framework of the UpWind
project (EU 6th Framework Program). The aim of our work has been
to contribute to enhance the knowledge on the performance of this
technology in complex terrain.
Particular cases of study have been the installation of a ZephIR lidar
in the proximity of a wind turbine and IEC-compliant meteorological
masts, in order to analyse the wind vector at various heights, wind
shear and turbulence. During 2009 we carried out a power curve
measurement according to IEC 61400-12-1, and in parallel used the
ZephIR lidar data to provide wind profile information, in order to obtain
a better understanding of the wind conditions across the rotor area,
and study its effect on power production.
At the moment, we are using ZephIR to keep on with lidar-related
research activities. In particular, within the SafeWind Project (EU
7th Framework Program), which focuses on extreme events,
we are working on the creation of a long-term database of lidar
measurements in complex terrain. One of CENER’s tasks in this
project is to investigate the benefits of new measurement techniques
(remote sensing) for resource assessment and forecasting purposes.”
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ZephIR - an integrated tool at CeNeR’s
experimental test site in complex terrain
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CAse study 2 : North AmericaNaikun Wind development Inc
IN 2006 NAIkuN begAN WoRkINg WIth NAtuRAL PoWeR oN A NoveL
APPRoACh to gAtheRINg WINd dAtA offshoRe foR the heCAte stRAIt
WINd fARm PRojeCt off the CoAst of NoRth West bRItIsh CoLumbIA. Not
WIshINg to ComPRomIse dAtA ACCuRACy by ReduCINg mAst INstALLAtIoN
Costs, NAIkuN Looked At Remote seNsINg teChNoLogIes As A WAy
foRWARd.
Over the following months NaiKun developed a world-class marine
meteorological station equipped with ZephIR as the sole on-site
resource assessment tool to provide a bankable wind regime across
the site, plus a number of other high-tech devices for measuring sea
current velocities and wave heights, periods and direction. All data is
transmitted in real-time to their wind resource managers in Germany,
and met-ocean managers in Victoria, BC. The data collected will
play an important role in pre-engineering the project and identifying
optimal siting of wind turbine locations.
“Natural Power’s ZephIR will improve our ability to profile
the resource by providing wind measurements within the
entire area of a turbine blade rotation; from base to hub
height within seconds. traditional anemometers provide
data, but only at one height and cannot capture other wind
characteristics like this particular LidAR system does,” noted
Peter Hunter, Vice President for Design & Planning at NaiKun
Wind Development. “the difference in technology is dramatic,
not unlike that between an x-Ray and Ct scan. Instead of a
snapshot of the resource, using ZephIR we can gain a multi-
dimensional understanding of the wind resource and several
characteristics at the project site. the data collected will be
used to optimise project design and layout of the wind farm.”
ZephIR has now successfully been gathering data on the station for
the past 12 months, acting as the sole on-site resource assessment
tool. The platform has been managed by GL WINDTEST - the world’s
leading certification body in the wind energy field.
GL WINDTEST has extensive experience in certifying onshore and
offshore wind energy products and projects, responsible for more
than 50% of all certifications. GL WINDTEST has been providing
NaiKun with operational support, data collection from the ZephIR via
SatComms, system integrity checks and the ongoing data analysis in
the Hecate Strait wind farm project.
Commenting on the success of the project, Detlef Kindler, Senior
Offshore Project Manager for GL WINDTEST highlighted that “one
critical performance indicator of such remote solutions
described here is availability and ensuring continuous data
collection. ZephIR has achieved 95% data availability for the
past 9 months demonstrating it’s reliability and suitability in
such challenging conditions.” Kindler also commented that “with
more than 3 years of operating ZephIR’s the system can now
be seen not as an emerging technology but as a product and
tool that wind engineers should call upon for wind resource
assessment. the Naikun project has clearly demonstrated
that ZephIR can assist developers not only onshore but now
offshore also.”
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“ZephIR has achieved 95% data availability
for the past 9 months demonstrating its reliability
and suitability in such challenging conditions.”
Meridian purchased one of the first production ZephIR systems back in 2005 and followed this by purchasing a further second system in 2008.
Paul Botha, Wind Technical Consultant at Meridian, explains how ZephIR is used across sites in New Zealand. “our ZephIR’s are extremely valuable in measuring from short masts at around 30m upto hub height at around 90m. short tilt-up masts are cheap to install and ZephIR can be placed next to the mast for periods of approximately 6 weeks to obtain good hub height measurements. We can also use ZephIR for micro-siting around a large site, returning to the mast as a reference point.”
In addition, Meridian are able to assess wind flow with ZephIR where access is difficult and terrain conditions mean a guyed mast may not be able to be installed. Botha notes “We measure wind shear across the entire rotor disk notably up to 130m, and can understand other wind characteristics such as inflow angle at turbine locations in complex terrain. We have also used ZephIR to provide a qualitative turbulence intensity assessment, measuring fluctuations in wind direction and eddies.”
Dougal McQueen, Research Associate at Meridian, has much field deployment experience having operated ZephIR’s for the past four years. “It takes me less than an hour to install our ZephIR and begin measurements at height. the reliability of the units themselves has been good and the casing’s composite plastic structure is extremely tough and well suited to the environment and rugged terrain here in NZ. ZephIR gives us better confidence than ever before that conditions at potential wind farm sites are acceptable.”
meRIdIAN eNeRgy geNeRAtes eLeCtRICIty fRom 100% ReNeWAbLe
ResouRCes WIth A PoRtfoLIo of hydRo ANd WINd geNeRAtIoN. IN
deveLoPINg WINd PRojeCts suCh As West WINd IN WeLLINgtoN ANd
te uku NeAR hAmILtoN It WAs CRuCIAL to obtAIN WINd dAtA quICkLy ANd
IN dIffICuLt teRRAIN - eReCtINg hub heIght meteoRoLogICAL mAsts WAs
Not feAsIbLe IN ALL LoCAtIoNs thAt WeRe IdeNtIfIed As RequIRINg WINd
meAsuRemeNts so they begAN LookINg foR A NeW methodoLogy.
CAse study 3 : New Zealand meridian energy Ltd
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“ZephIR gives us better confidence than ever before
that conditions at potential wind farm sites
are acceptable.”
CAse study 4 : denmarkRisø dtu
the dANIsh WINd tuRbINe INdustRy hAs A 40% shARe of the gLobAL
mARket ANd emPLoys moRe thAN 20,000 PeoPLe, mAkINg It the WoRLd
LeAdeR IN WINd PoWeR. some 20% of deNmARk’s domestIC eLeCtRICIty
PRoduCtIoN Comes fRom WINd. the deveLoPmeNt of WINd PoWeR IN
deNmARk Is ChARACteRIsed by A CLose CoLLAboRAtIoN betWeeN PubLICLy
fINANCed ReseARCh ANd INdustRy IN key AReAs suCh As ReseARCh
ANd deveLoPmeNt, CeRtIfICAtIoN, testINg, ANd the PRePARAtIoN of
stANdARds. RIsø dtu PLAy A PIvotAL RoLe IN PRovIdINg thIs R&d to
deNmARk’s gRoWINg WINd INdustRy.
In January 2004, Risø DTU took delivery of the first ZephIR prototype, and shortly afterwards used it to perform the first lidar comparisons against their tall mast at Høvsøre. Since then, Risø have tested over a dozen ZephIR systems for the purposes of:
• IndependentcorrelationsforcustomersusingZephIRas the sole source of anemometry on projects
• OngoingZephIRresearch&development• Developmentofnewproductsandalgorithms• TraceablecalibrationforNaturalPower’sZephIR
reference system
Torben Mikkelsen, Professor in the Wind Energy Division at Risø DTU, commented in 2004 that “Lidar nowadays gives rapid, reliable and accurate measurements. Notably, the technology permits wind yields to be determined at heights significantly above the furthest reach of the highest wind turbines and offers great deployment flexibility”.
The relationship between Risø DTU and Natural Power has flourished with much ongoing work involving the use of ZephIR. One such example is the recent world’s first installation of a lidar in the spinner of a wind turbine - this particular development is detailed on the next pages under ControlZephIR.
“We have been working with Natural Power ever since the very first ZephIR unit was trialled; from the start the product combined revolutionary ideas with high accuracy, and we have seen this further improved over the following years. the ZephIR team at Natural Power has always been open to developing the product, both in improving its performance and also its use in novel applications, for example the turbine mounted application and ‘Windscanner’. [Windscanner is a system combining three steerable ZephIR lidars providing 3-D wind and turbulence measurements - see www.windscanner.dk for more information].
We very much see lidar as an essential tool for the future of both the wind energy research community and the wind industry.”
- WINd eNeRgy dIvIsIoN, Risø dtu
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“since the very first ZephIR unit trialled, the product
combines revolutionary ideas with high accuracy.”
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ControlZephIR™ - WoRLd fIRsts
the INCoRPoRAtIoN of AdvANCed WINd dAtA fRom ZephIR INto tuRbINe
CoNtRoL systems offeRs oWNeR / oPeRAtoRs the PossIbILIty of ImPRoved
eNeRgy yIeLd ANd LoAd ReduCtIoN by ComPeNsAtINg the effeCts of yAW
eRRoRs, gusts ANd stRoNg WINd sheAR. ZephIR WAs the fIRst LIdAR to
be INstALLed oN AN oPeRAtIoNAL tuRbINe bACk IN 2003. NoW, NAtuRAL
PoWeR hAve WoRked WIth RIsø dtu to AChIeve the WoRLd’s fIRst LIdAR
meAsuRemeNts fRom A RotAtINg tuRbINe sPINNeR / hub.
In September 2009 Risø DTU reported their latest results from a fast data acquisition continuous wave (cw) wind lidar - ZephIR - which has been installed and operated in the rotating spinner of a large 80 m diameter, 59 m hub height Vestas NM80 wind turbine located at Tjæreborg Enge in western Denmark. To the best of Risø knowledge this achieved a “World first” successful operation of a forward looking wind lidar integrated in the spinner of an operating wind turbine. This new measurement concept has allowed an unimpeded view of the approaching wind field, which has been interrogated using several different scan patterns. Information on wind speed, shear and direction has been extracted and compared to the output from an adjacent met mast.
Torben Mikkelsen, Professor at Risø DTU, reported “our results encourage development and integration of continuous wave wind lidar technologies in the area of active turbine control and improvement of wind turbine performance. during the test period ZephIR has shown excellent reliability and data availability was very high throughout the 4 month measurement period.”
PeRfoRmANCe ZephIR
Range (min.)Range (max.)
10 metres200 metres
Probe length @ 10 mProbe length @ 100 m
0.07 metres7.70 metres
Heights measured 5 (user configurable)
Sampling rate 50Hz
Averaging period 1s upwards (user configurable)
Scanning cone angle 30° (other angles available)
Speed accuracy* < 0.5%
Speed range 1 m/s to 70 m/s
Direction accuracy* < 0.5°
oPeRAtIoNs ZephIR
Temp range (min.)Temp range (max.)
-25°C+40°CExtendable range achievable
Power consumption 100 Watts**
Power input 28 V
Weight including 12 - 24h battery back-up
134 kg
dAtA ZephIR
10 minute averaging 80K / day
3 second data 3MB / day
sAfety ZephIR
Laser classification Class 1
Eye safety standard IEC 60825-1
IP Rating IP65
Compliance Full CE accrediation
ZephIR has integral batteries providing 12 - 24 hours back-up power.
* as measured against a calibrated moving target
** in normal operating conditions (-13°C to +25°C)
teChNICAL sPeCIfICAtIoN
ControlZephIR installed - 2009
ControlZephIR installed - 2003
ValparaisoLautaro Rosas 366Cerro Alegre, ValparaisoCHILE
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