OREF wind database report - 2015

1/2/16

2015 OREF Feed In Tariff wind report

This report has been produced based upon the data collected by OREF during 2015 on the

generation of electricity from wind turbines in Orkney. The turbines attract Feed In Tariff support.

The database has now been running for a number of years and some examination of the data

contained was felt to be useful.

Catchment:

The database is confidential, voluntary and participants have been recruited to the initiative. No

payments are made for the data and

participants are free to leave at any

time. An example of a month’s

report is attached as Appendix A.

At the end of December the total

number of registered participants

was 96 (up from 61 at the end of

2014) with a combined installed

capacity of 2,174kW.

There are 661 FIT eligible wind

generators in Orkney as of the end

of 20151. 576 of these are domestic

with a combined capacity of

4,430kW (average 7.7kW). The

remainder (85) of non-domestic

turbines account for 9,787kW

(average 115kW).

The database participants therefore

represents approximately 14.5% of

the number of generators or 15.2%

of the installed FIT eligible wind capacity in Orkney. Fig 1. Map of participating

generators. Colour denotes size.

Note: although originally envisaged as a micro-generator database it recruited a large 900kW

machine. This machine alone contributes 40% to the total output figures, however interestingly it is

not the highest load factor machine.

Lately the database has also attracted non feed in tariff participants with large machines. For the

purposes of this report these have been excluded from the analysis. Their future incorporation is

considered in the report.

1 https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/493947/December_2015_Sub-regional_Feed-in_Tariffs_confirmed_on_the_CFR_Statistics.xls

Types of participating machines:

Analysis of the types of turbines shows that they are predominantly (49%) 5KW Evance machines

and 21% C&F 20kW.

Fig 2. Types of turbines in database.

SMA have supplied the majority (63%) of the inverters.

Fig 3. Types of inverters in database.

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Turbine Manufacturer

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Inverter Manufacturer

Installers:

The machines have been installed by fairly evenly distributed number of companies. Note: The data

sample may be skewed by the willingness of the installers to engage their customers with the

database.

Fig 4. Installers of turbines in database.

Performance:

Due to machines being recruited to the database during the year it is difficult to ascribe precise

value to the energy generated. In addition some difficulty has been experienced with getting

readings from some participants.

At year end 1/3rd (34) of the possible 95 readings for the year were incomplete. There is no

information as to how many of these missing readings are ascribed to break-downs & how many to a

failure to submit readings. These have been excluded from the analysis.

Since all machines started at zero kWh on their installation date, and their performance is known at

the end of 2015, an average load factor can be derived from the fleet to date. This is 37%

Taking the 14,217kW of wind generation in Orkney on the Government FIT register and applying the

average load factor would give a possible delivered generation of 46,080,140kWh or 46GWh in 2015.

CO2 emissions avoided:

The UK’s electricity system as a whole continues to be dominated by fossil fuels. Renewables are

making inroads into that, but are variable. A total carbon emission figure is difficult to derive,

however the UK uses a number of figures for carbon density that range between approximately 350-

450 kg/MWh.

Taking the mid-point of 400kg/MWh would indicate an avoided carbon emission of approximately

18,400 tonnes of CO2

AEC

BJRE

C&F

Enercon

Evance

Orkney Business Ring

Orkney Micro-Renewables

Orkney Renewables

PMR

Sangster Electrical Ltd

Tempest Energy

WES

West Coast Energy

Alternative Energy Store

Based on the available performance figures of one highly monitored machine overall yield in 2015

was comparable to 2014. The machine is a 5kW Evance and features in the middle order in the

monthly ranking. (Note: installation part way through 2012)

Fig 5. Extract of Sunny Portal public data for Quarry House, Finstown

Output through the year largely followed the expected pattern. (Note: May’s ‘mean value’ is low due

to 2012 start value)

Orkney as a whole:

Data has been obtained from SSE’s website showing the nett power-flows in the county.

Unfortunately a change in the website led to a loss of this data feed in October. Although restored in

2016 this has resulted in a temporary data gap between October and year end. Effort is being made

to recover the missing data.

It is not clear if Orkney was a nett exporter of power in 2015 at the time of writing this report

although it has been for the previous 2 years. The FIT generators would have been a small

contributor to this position compared to the industrial wind turbines, however it remains of interest

to the FIT community.

Revenue received:

The Feed In Tariff for wind has been cut several times of late. The following table shows the Feed In

Tariff for installed wind capacity between 1.5kW and 1500kW.

Dates applicable p/kWh

1.5-15kW 15-100kW 100-500kW 500-1500kW

1 April 2010 to 31 March 2012 31.53 28.51 22.16 11.19

1 April 2012 to 30 November 2012 30.12 27.33 22.16 11.19

1 December 2012 to 31 March 2014 22.59 22.59 18.83 10.21

1 April 2014 to 30 September 2014 18.06 18.06 15.06 8.17

1 October 2014 to 31 March 2015 16.26 16.26 13.55 7.36

1 April 2015 to 31 March 2016 14.45 14.45 12.05 6.54

The earliest turbine in the database was installed in Feb 2007, the most recent in September 2015.

An estimate of the FiT for each machine has been made based on the date of installation and gives

an average FIT of approximately 27.53p/kWh (excluding the single 900kW machine).

It is unclear as to the total revenue received by the county due to different ownership models of the

machines and the various dates of installation. Based on the known installed capacity of domestic

machines alone (4430kW) and a 75% local ownership at the average FIT from the database

(27.53p/kWh) and 37% load factor the likely income to the county is of the order of £3M2 in 2015.

Other machines will add to this total.

From other work done the likely cost to the electricity consumers in Orkney of the FIT scheme is

approximately £120k.

2 4430kW installed x 8760 hours x 37% load factor x 27.53p/kWh x 75% local ownership = £2,964k ~£3M

Weather:

Wind speed data is obtained monthly from Kirkwall airport via EMEC. The mean wind speed for the

year was 6.8m/sec (15.2mph). The monthly distribution of wind direction is as shown by the wind

roses below.

Jan Feb Mar Apr

May June July Aug

Sept Oct Nov Dec Fig 6. Monthly wind direction at Kirkwall airport 2015

Overall the wind was from the south and west as shown by the wind rose for the year

Fig 7. Annual wind direction at Kirkwall airport 2015

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SESSE

SSSW

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Correlation of average wind speed and output:

The load factors of machines reported in any given month were plotted. The length of each line

being indicative of the number of machines reporting on a month.

Fig 8. Ranked load factors per month. Mean wind speed shown.

Taking the monthly figures at the 10th point there is a good correlation between wind-speed and

load factor in the month (the correlation is similar at other readings, but weakens at lower load

factors).

Fig 9. Correlation of 10th ranked load factors in month against mean wind speed.

The overall conclusion being that there is a reasonable correlation between energy generated and

mean wind speed for the prevailing wind directions.

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100%

1 4 7 10 13 16 19 22 25 28 31 34 37 40 43 46 49 52 55 58 61 64

Load

Fac

tor

Number of Ranked Submitted Readings

9.3m/sec -Jan 15

8.3m/sec -Dec 15

8m/sec -Feb 15

7.9m/sec -Dec 14

7.7m/sec -Mar 15

7.4m/sec -Nov 15

6.83m/sec -Oct 14

6.8m/sec -Nov 14

6.7m/sec -May 15

6.1m/sec -Aug 14

6m/sec -Apr 15

6m/sec -Oct 15

5.9m/sec -June 15

5.7m/sec -Sep 15

5.6m/sec -Jul 15

5.5m/sec -Aug 15

4.7m/sec -Sep 14

4.65m/sec -July 14

4.17m/sec -June 14

0%

10%

20%

30%

40%

50%

60%

70%

80%

0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0

Load

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Mean Wind Speed

Faults:

Faults have been reported throughout the year and have been categorised.

Collision related 2

Communications related 6

Grid outage that left a problem 4

Inverter related 25

Multiple issues 3

Tower related 1

Turbine related. 56

None of the above 15

50% of the 112 faults reported have been with the turbine, 25% with the inverter.

26 users have had multiple problems in the year, 14 a single problem. This means approximately half

of the participants have had a problem of some type or another in the year showing the importance

of effective servicing and monitoring.

Fig 10. Distribution of number of faults reported.

Three patterns emerged through analysis of the database and by polling owners with specific turbine

types:

1. Some C&F machines were suffering from inadequate reactions to faults leading to extended

periods of lost production. Representation was made to the manufacturer on this point and

more effort seems to have been deployed to rectify the problems.

2. A loss of performance on Kingspan/Proven machines was identified following service.

Anecdotally this appears to be due to poor quality springs being used in services.

3. Some Evance machines have shown unexpected wear in pitch bearings leading to a

reduction in gust response and subsequent surges in output leading to trips. Replacement of

bearings at service has dealt with this issue.

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Number of faults

Interrogation:

A question was posed as to the scale of any grid restriction avoidance activities. The limit of 3.6kW

per phase imposed by SSE has led to a number of innovations to soak up additional power over and

above this limit. The contact details on the database allowed this to be investigated and of the

machines in the database a total of 15 have such measures and most of these divert the excess into

base load heating.

Recruiting:

OREF is keen to see the database extended by capturing as many generators as possible. There are

presently nearly 450 machines not on the database, so there is plenty of opportunity to expand the

initiative.

OREF also runs parallel databases seeking performance data from solar panel owners and on the

demand side; Electric Vehicle owners (EVs). It is likely that other strands of data can also be

assimilated over time and ideas would be welcome on what else to add, to ask and how best to

recruit.

The introduction and collation of larger wind generators may also grow in future. Given the

commercial nature of such machines it is likely that there may only be limited uptake in this

community based initiative.

Getting involved:

If you would like to get involved, or know someone else with a turbine (or solar panel, or electric car)

who would be willing to contribute their figures then please ask them to mail fit@oref.co.uk and the

free registration can be instigated.

The more people we have the more representative and useful the data to show Orkney’s

performance and experiences.

Neil Kermode

3/2/16

© OREF 2016

Example of Monthly report – October 2015 Appendix A Orkney Micro-generators (wind) Monthly results table September 2015 Posted 09/10/15

Number of generators registered at month end: 89 New generators registered this month: 0 Number who have ever submitted readings: 86 Number of readings submitted this month: 56 Number classified as ‘late’ i.e. >45 days: 33 Number able to be ranked: 54 Mean wind speed at airport: 5.7m/sec

Results for September month based on load factor this month:

Rank User ID Machine

Rating (kW)

Load

Factor this period

Date of Installation

Days since installation

Load factor to date

1 1770 5 59% 18/12/2012 1017 13%

2 1780 5 46% 18/02/2013 955 16%

3 1760 5 45% 18/02/2013 955 17%

4 1820 10 44% 19/06/2013 834 69%

5 1230 5 43% 30/03/2012 1279 50%

6 1320 5 42% 22/01/2012 1349 38%

7 1810 5 42% 16/07/2011 1538 47%

8 1090 20 41% 19/05/2012 1230 34%

9 1800 2.1 41% 09/07/2012 1180 42%

10 1720 10 38% 09/08/2011 1514 16%

11 1460 5 38% 19/01/2014 619 44%

12 1190 5 38% 03/09/2012 1122 42%

13 1730 5 37% 06/08/2011 1517 5%

14 1700 5 36% 05/08/2011 1488 21%

15 1840 5 36% 05/09/2012 1120 71%

16 1270 5 36% 27/02/2014 582 27%

17 1030 20 35% 11/07/2012 1149 28%

18 1360 5 35% 06/03/2012 1308 42%

19 1530 5 35% 31/03/2014 549 40%

20 1660 6 35% 01/05/2008 2709 23%

21 1480 5 34% 06/07/2012 1182 39%

22 1470 5 33% 06/07/2012 1182 38%

23 1750 5 33% 10/12/2012 1025 41%

24 1280 10 33% 19/02/2013 956 33%

25 1300 11 32% 02/07/2012 1185 44%

26 1065 20 32% 23/06/2012 1194 36%

27 1400 5 32% 20/08/2012 1138 39%

28 1830 5 31% 05/09/2012 1121 38%

29 1290 900 31% 01/10/2009 2190 37%

30 1210 5 31% 20/12/2013 622 33%

31 1370 5 30% 15/01/2014 628 40%

32 1130 6 30% 10/06/2010 1938 35%

33 1390 6 29% 10/09/2009 2212 35%

34 1100 6 29% 17/10/2012 1078 39%

35 1120 80 29% 17/09/2012 1078 38%

36 1510 6 29% 01/05/2012 1249 35%

37 1790 5 28% 13/12/2012 1022 28%

38 1110 80 28% 06/11/2012 1058 31%

39 1070 5 27% 25/08/2011 1468 30%

40 1040 5 27% 16/04/2012 1263 36%

41 1020 5 27% 20/10/2012 1076 39%

42 1180 5 26% 30/11/2012 1005 35%

43 1220 5 25% 03/09/2012 1122 35%

44 1260 6 24% 23/03/2014 558 31%

45 1060 20 24% 23/06/2012 1194 35%

46 1420 5 23% 21/08/2013 740 36%

47 1670 6 23% 20/08/2008 2598 20%

48 1140 5 22% 19/07/2012 1169 38%

49 1310 80 21% 26/09/2013 735 32%

50 1340 80 20% 01/10/2013 730 29%

51 1150 6 19% 20/02/2012 1319 25%

52 1680 6 18% 01/06/2008 2678 19%

53 1410 5 3% 01/07/2012 1190 41%

54 1170 5 1% 01/07/2012 1188 43%

The total electricity generated by these turbines since their installation now amounts to 26,542,000 kWh3. A very small number of those on the database spill electricity at high

levels so not ALL is used. However the cumulatively the ‘fleet’ saved approximately 12,421 tonnes of CO2 being emitted4 based on average emissions in UK. The fleet has a total of 101,256 days experience to date.

Faults reported: 6 faults were also reported. In total there were: 2 turbine related problems, 3 inverter faults and 1 tower problems.

More details will be sought on this when time permits.

3 All figures are subject to correction in the event of mis-entered figures being discovered. 4 UK Average emissions 9/10/2015 = 0.468kg CO2/kWh – gridcarbon app.

Monthly comparison. The graph below shows the comparison of load factors in a month with the mean wind speed for the month shown in the key. The length of the trace is due to the different number of generators on the database in a month that returned readings.

This month the key is sorted by wind speed and it shows a reasonable correlation between wind speed and load factors. Ignoring the highest values which sometimes are due to double entries the slope of the lines are pretty parallel…. except the highest one (Jan 2015) which drops off fast…. Any idea why?

Load factors up to September 2015

Load Factors September 2015

Notes about the load factor. The load factor is the percentage of time that the turbine delivers its rated output. So a 10kW unit running flat out for a 30 day month would generate 10kW x 24 hours x 30 days = 7200 kWh. If in the month a turbine delivered 3000kWh it would have a load factor of 3000/7200 = 0.416 or 41.6%

In these calculations we take the number of hours between readings rather than in a month, so it is difficult to strictly compare machines over a month. It could be a really windy start to

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1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 41 43 45 47 49 51 53 55 57 59 61 63 65

9.3m/sec -Jan 15

8m/sec -Feb 15

7.9m/sec -Dec 14

7.7m/sec -Mar 15

6.83m/sec -Oct 14

6.8m/sec -Nov 14

6.7m/sec -May 15

6.1m/sec -Aug 14

6m/sec -Apr 15

5.9m/sec -June 15

5.7m/sec -Sep 15

5.6m/sec -Jul 15

5.5m/sec -Aug 15

4.7m/sec -Sep 14

4.65m/sec -July 14

4.17m/sec -June 14

the next month and people might submit late. However this will smooth itself out over time as the time period gets longer.

It is also possible that a misread figure can distort it too and although some can be easily traced to transposed numbers. There were some examples of values entered more than once which have to be hunted out, some just remain a bit ‘odd’ such as the 116% listed. They too will wash out over time.

Wind Direction:

Notes about wind direction. The wind rose below is a graphical method of describing the

wind in a period. This counts the time that the wind is in a given direction. The prevailing wind generates a ‘petal’ from that direction. (This month was mainly divided both Southerly and Northerly). A perfect circle would mean that the wind came from all directions equally. This may be useful to correlate wind direction to performance on an individual site.

Wind Rose September 2015

Orkney’s electricity flows.

The power flows as measured by OREF member Aquatera and published by SSE are as below with the gross figures indicating approximately ~7.7 GWh of metered demand and ~11.2 GWh of metered generation. This means Orkney generated the equivalent of around 144% of its publicly metered electricity from wind in May. The generation from the micro-

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SSE

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generator fleet is largely unseen by SSE and the demand satisfied by onsite use is also unknown.

On the basis that there is approximately 5MW of wind microgeneration and the submitted readings show a 35% average load factor it is reasonable to be believe that microgeneration wind contributed approximately 5MW x 24 hours x 30 days x 35% = 1.26 GWh in September.

Measured electricity flows September 2015

© OREF 2015