Operational experience with 6 meteorological stations installed in and Umanak.

Kurt S. Hansen1*, Martin O.L. Hansen1 & Poul Linnert2

1Fluid Mechanics, Department of Mechanical Engineering, Technical University of . DK- 2800 Lyngby, Denmark

1The Arctic Technology Centre, Department of Civil Engineering, Technical University of Denmark. DK-2800 Lyngby, Denmark

* Speaker, e-mail: [email protected]

Abstract "Projekt Fyrtårnsbygd" and Nukissiorfiit has funded 6 meteorological stations, which have been installed in Sisimiut and Umanak communes in during 2006. Measurements from the first operational year have been analysed. The major findings are the wind speed distributions and power density for each of the 6 locations. The wind resource measurements are recorded with automatic measurement equipment, but the data transfer resulted in some data losses. Furthermore one of the measurements systems failed completely during wintertime, which was discovered during the summer inspection resulting in a data loss.

Resumé Til bestemmelse af lokale vind resurcer ved 6 bygder beliggende i Sisimiut og Umanak kommune i Grønland har Nukissiorfiit og "Projekt Fyrtårnsbygd" finanseret opsætning og drift af 6 automatiske målestationer. Denne artikel beskriver dels de udvalgte lokaliteter og dels erfaringer fra det første driftsår. De indsamlede målinger kvalitetskontrolleres og gemmes i en database på DTU, som kan anvendes af alle projektdeltagere.

1. Introduction

Increasing oilprices and huge distribution 2. Site selection cost for energy to the small settlements in Greenland has initiated an investigation of The sites are located in Sisimiut and local energy resources eg. wind, solar and Umanak communes in the westen part of hydro power. This article concentrates on Greenland. The 6 different sites have mainly reporting the wind resource measurements, been selected based on communication with which has been operational since autumn people living at the sites. The geographical 2006. The wind resource measurements are coordinates for each site is listed in Table 1. recorded near Dumpen and Sarfannguaq, The site selection has been subject to both in Sisimiut Community. Furthermore several restrictions to enable access for the wind resources are measured in 4 equipment, which has to be carried and different locations in Umanak commune eg. installed by pure manpower. Installation of Umanak, Saattuut, and . all masts was done by 2 persons, which carried all equipment to the site and drilled met.station is located on a local hill (100m wholes in the mountain for anchoring the asl.) - above the settlement with free inflow guiding wires. from all directions, except western direction, which is dominate by peaks. All other Table 1: Location of measurement sites. directions are dominated by a mixture of Site N W Height water and lower peaks, Figure 2. asl Dumpen 66°55,609 53°40,057 78m Sarfannguaq 66º53.716’ 52º51.977’ 100m Umanak 70º40.214’ 52º07.224’ 300m Saattuut 70º08.411’ 51º07.184’ ? Ikerasak 70.29°468’ 51°17.509’ 100m Ukkusissat 71º03.178’ 51º52.501’ ?

Detailed site documentation and pictures are available on the project page [1]. Figure 2: Sarfannguaq seen from seaside towards S and with the mast on the top. 2.1 Dumpen

Dumpen is a 78m hilltop located south of 2.3 Umanak Sisimiut, Figure 1 in a distance of approximately 1 km from the town [2]. The The mast is located 300 m asl. in the inflow from SW to NW is almost undisturbed mountains outside the settlement in a gorge from the seaside, while the flow from with plenty of wind. From the mast we can Eeastern direction is highly influenced by the see beautiful peak named "Hjertebjerget" mountain “Kællingehætten” with a height of and opposite to this is a view downtown to 778 m. Inflow from the Northern direction is the settlement Umanak. 150m towards west highly influenced by Sisimiut town. is a clean water reservoir lake with resticted access. Access the measurement location starts behind the football ground following a water pipeline with 600m steep ascending up to a flat plateau, Figure 3.

Figure 3: The ascending path to the metmast at Umanak, along the pipeline. Figure 1: Dumpen with the mast and “Kællingehætten” behind, seen from 2.4 Sattuut SW. is a small island located 10 km north of “Storøen” between several other islands. 2.2 Sarfannguaq The weather around this island is rather Sarfannguaq is located at the eastern part of unpredictable, which results in bad access a West-Eastern narrow island, [2], that is conditions. located in a fiord south of Sisimiut. The The mast is located on a plateau outside the 2.6 Ukkusissat settlement, near a helipad, which influenced Ukkusissat is located 45-50 km north of the site selection, Figure 4. Umanak, where the mast is located on a

small ridge above the settlement. From the mats there is a magnificent view to the settlement and “Uummannaqfjorden”, Figure 6. This location has been pointed out as the windiest site by the local inhabitants.

Figure 4: Measuring site on Sattuut - seen towards SE.

2.5 Ikerasak

The area 30 km from Umanak towards SE is Figure 6: Picture taken from the dominated by "Umanatsiaqfjeldet" and a measuring site at Ukkusissat - towards settlement is located below the fell. The SW. mast is located on a small hill between water, the settlement and the mountain. A Much more pictures taken during the visit gives an impression of a tough and installation are available from project web- windy climate, Figure 5! site, [1].

3. Measurement equipment The measurement equipment is based on a standard NRG-system with sensors for measuring wind speed, wind direction and temperature. All the instrumentation including the logger are mounted on a 10m guided mast, shown on Figure 7. The NRG-Symphonie logger, which is integrated with a NRG-iPack communication unit, is located at the bottom of the mast. The masts in Sarfannguaq and Umanak is furthermore equipped with sensors for recording precipitation and solar radiation. The sensors have not been selected for operation under artic conditions while no power is available for heating the instruments during winter. The communication unit is powered from a separate battery, charged from solar panels

Figure 5: Mast located at Ikerasak, but the data is only transmitted when there seen towards SE. is sufficient power on the batteries. they are made public accessible on the Internet [1].

3.3 Data quality and problems The data availability, during the first operational year, has been rather low, Table 2. The reasons have mainly been the manual data transfer and defects on logger and sensors, which was fixed during site visits in September 2007.

Table 2: Summary of data ult. September 2007. Site Year hours availability Dumpen 2004 3478 - - 2005 5030 57% - 2006 6467 84% - 2007 5767 88% Sarfannguaq 2003 3527 96% - 2004 4940 97% - 2006 3173 66% - 2007 5855 89% Umanak 2006 1036 28% - 2007 663 10% Figure 7: NRG-Measurement system. Sattuut 2006 1848 100% - 2007 939 14% 3.1 Data recording and transmission Ikerasak 2006 1833 100% - 2007 6246 95% All signals are recorded with 0.5 Hz and Ukkusissat 2006 1909 99% stored as 10 minute statistical values - 2007 4039 62% (mean, stdev., min and maximum) on a SD- card, which can be replaced by a local Dumpen is well represented in the database operator. Data transfer to a central database and includes 2 complete years. at DTU-Lyngby from each site, is activated Sarfannguaq is well represented and daily through the GSM network, using a includes 2 complete years. TELE-Greenland Internet server – except Umanak is very poorly represented. from Sarfannguaq, which has not yet been Sattuut is very poorly represented. upgraded for automatic data transmission. Ikerasak is lightly represented with almost The automatic data transmission stopped one year of valid measurements. November, 13 2007 from all stations, due Ukkusissat is poorly represented. insufficient power for the iPacks, probably caused by snow covered solar panels. 4. Wind speed distributions 3.2 Data control and access Based on the recordings, listed in the During the first operational year, all data previous chapter, the mean wind speed and was retrieved from the loggers by local wind speed distribution have been operators, which caused data losses during determined for each site. The wind speed the transmission phase. During the second distribution is described with a Weibull operational year all loggers were extended distribution, which are defined with a scaling with an automatic data transmission system parameter A and the shape factor k. The site based on the GSM network. Data from parameters are listed in Table 3. each location is received daily on a central mail-server located at DTU-Mekanik, Lyngby. The data are quality checked before Table 3: Mean wind speeds the weather is highly influenced by passing and power densities. low pressure systems resulting in a quite Sites Vmean A k Power windy climate. Further north it is generally m/s m/s - W/m2 less windy. The met masts in Sisimiut Dumpen 4.9 5.3 1.28 261 Commune are situated in the southwest Sarfannguaq 6.0 6.8 1.97 256 zone, where the wind direction in the winter Umanak 6.5 7.3 1.82 354 time mainly is from the north accompanied Sattuut 4.3 4.8 1.73 106 by cold and clear air. A southern wind in Ikerasak 3.2 3.4 1.20 76 connection with lows passing through the Ukkusissat 3.8 4.3 1.91 66 Davis Strait gives rough weather with very strong winds in coastal areas followed by an The promising wind resource seems to be at increase in temperature and precipitation. In Dumpen and Sarfannguaq. connection with Foehn effects (see later) the • The wind speed distribution measured at temperature can in shorts periods in the o Dumpen results in a high, but “narrow” winter get as high as 10-15 C. Outbreaks of power density distribution because all cold air from Canada can create polar lows the energy is located at low wind speeds over the sea that may reach the coast compared to Sarfannguaq. followed by strong winds, hard frost and • The wind speed distribution at snow. In the summer time lows passing Sarfannguaq has a more common from south and southwest through the Davis distribution with a shape factor k≈2. Strait are quite frequent, creating just as in • The high power density value for the winter time strong winds and Umanak is probably not representative, precipitation. In the fjords the wind speed is because it is only based on limited (high generally lower than along the coast. Stable wind) periods, recorded during the summer weather is created in connection winter 2006/2007. The potential for this with a high pressure system over central site could is expected be high, because Greenland. of the free inflow from SE-NW, which The other four masts, see sections 2.3 to seems to be dominating wind direction at 2.6 are placed in the northwest zone, where Dumpen and Sarfannguaq. the weather is colder but less unstable. Just, • Sattuut has a very low mean wind speed as in the southwest zone the strong winds and power density, but the number of are mainly from the south associated by measurements is low. This site might lows in the Davis Strait moving towards have a limited potential because of the Baffin Bay. In the inner part of the Disko shadow from the SE-S-NW sectors Bay occasional strong Foehn from southeast caused by the mountains. may occur. The mean wind speed peaks in • Ikerasak has very poor wind resources - the autumn and falls again when the sea is according the first year of frozen. measurements, despite a free and The topology of Greenland is very complex undisturbed inflow sector from SE-SW. with many fjords and small mountains that • Ukkusissat has also very poor wind disturb the overall wind. The wind may thus resources, according to the first year of be reduced in the lee behind a mountain or measurements, probably because of the may be increased when e.g. concentrated in mountain shadows from SE. a valley. Further, a so-called katabatic wind occasionally occurs, where cold and thus heavy air from the ice cap starts 5. Data analysis and other projects avalanching towards the coasts. This is an adiabatic process where no heat is In a report from DMI [4] a general picture of exchanged with the surrounding air mass, the wind climate in Greenland is given based but due to compression the air heats up on a few long term measurements. A small approximately 1oC per 100 m. Depending on summary from the report is given as a whether the avalanching air is warmer or complement to the measurements. In the colder than the air at the coast, it will either southern part of Greenland, situated at be felt as a warm Foehn wind or it will approximately the same latitude as Oslo, completely push the coastal air into the during the winter for lights and heating. water resulting in a strong wind. Figure 10 shows the average wind speed at Only results from the two sites in Sisimiut Dumpen in the period 2004-2007 and a Commune will be included in this paper, similar behaviour as in Sarfannguaq is since the other masts have not been erected observed. After having measured in one long enough to give a reliable picture of the point for some time, preferably, more than wind resource. The mast in Sarfannguaq one year, it is possible to extrapolate the was erected in August 2003 as part of a findings in an area around the site to course in Arctic Technology at DTU, where investigate potential good and windy sites to the local wind resources should be place wind turbines. Often this is given as a measured and analysed to asses the resource map, showing kinetic energy possibilities of erecting a small wind turbine content in the wind per area (kW/m2). An to save diesel and thus money in the local often used tool is the WASP code from Risoe community. The measurements are still [6] that takes into account the effect of the ongoing and thus a period of four years is height contour, the surface roughness and covered. Figure 8 shows an example of a local obstacles. A result for Sarfannguaq, [7] time history at Dumpen recorded between is shown in Figure 11. In very complex the 4th and 5th February 2007, where the terrain like in most coastal places in sudden increase in temperature of 16 Greenland, especially the flow model based degrees Celcius followed by an increase in on the height contours is not perfect and wind speed from 5 m/s to 25 m/s indicates a some fixes exist, but this introduces some Foehn driven flow. uncertainty to the data. However, such resource maps can be used, together with Foehn driven flow - measured at Dumpen 4-5 feb. 2007 30 logistic consideration of cabling, roads etc.,

20 when deciding where to place potential wind 10 turbines, and to estimate the annual power ws - m/s ws - 0 04-Feb-2007 05-Feb-2007 06-Feb-2007 output and thus the economy of the project.

400

200 wd - deg - wd 0 04-Feb-2007 05-Feb-2007 06-Feb-2007 Sarfannguaq, h=10 m

8 20 7

2003 0 6 2004

T - DegC T - 5 2006 -20 04-Feb-2007 05-Feb-2007 06-Feb-2007 2007 4 Mean wind speed - m/s 3 Figure 8: Wind speed, wind direction 0 1 2 3 4 5 6 7 8 9 10 11 12 and temperature, measured at Dumpen Month between 4th and 5th February 2007. Figure 9: Monthly mean wind at Sarfannguaq during 2003-2007. It is also noted that the wind direction is around 100o that is directly from the ice cap. In Figure 9 the monthly variation of the mean wind speed in Sarfannguaq is plotted for the period 2003-2007 and it is seen that the wind speeds in the winter month October/November-February/March are around 6-8 m/s and higher than in the summer months, where the wind speed is around 4-5 m/s. This annual variation is not unexpected since the low pressure systems are generally stronger in the winter time, but is beneficial for the use of wind energy since the energy requirement is higher turbine also the potential use of the power Dumpen, h=10m must be taken into consideration. 9 8 7 6 2004 5 2005 4 Acknowledgements 3 2006 2 2007 1 The projects “Fyrtårnsbygd-083” and “Vind- mean - m7s wind speed 0 og solenergi i commune” are 0123456789101112 Month acknowledged for supporting the project.

Figure 10: Monthly mean wind at Dumpen during 2004-2007.

Figure 11: WAsP resource map (AEP) for Sarfannguaq, based on measurements from 2003-2007.

6. Conclusion References [1] Online wind measurements: The paper describes six different sites on http://winddata.mek.dtu.dk/Greenland the west coast of Greenland, where a [2] Fyrtårnsbygd – 083 Sarfannguaq, metmast has been erected specifically to Forprojekt, ARTEK/Nukissiorfiit-Januar 2007 estimate potential use of wind energy in [3] Vind- og solprojekt I Uummannap Greenland. A very short period of data has Kommunia, Forprojekt, ARTEK/Nukissiorfiit- been measured at the four sites near the December 2006 and therefore no conclusion can [4] Cappelen J, Jørgensen BV, Laursen EV, be drawn here. However, the wind resources Stannius LS, Thomsen RS. at Dumpen and Sarfannguaq, where the Klimaobservationer i Grønland, 1958-99- wind speed has been measured for several med klimanormaler 1961-90. DMI Technical years, seems to be interesting in a wind Report 00-18. energy perspective. To find a suitable wind [5] Henrik S.Iversen, Jakob S.Kristensen, (in Danish) “Vindresourcer i Grønland”, student report of 11422 Arktisk teknologi, DTU, 2003 [6] Wind Atlas Analysis and Application Program, WaSP 9; Risø-DTU 2007 [7]Vind potentiale I Sarfannguaq by A.F.Mølgård & J.N. Kastvig, Center for Arktisk teknologi, DTU, Dec.2008 (in danish)