EDF EN Canada Development Inc.

Transcription

1 Decision D Blackspring Ridge Wind Power Plant March 2, 2016

2 Alberta Utilities Commission Decision D Blackspring Ridge Wind Power Plant Proceeding Application A001 March 2, 2016 Published by the: Alberta Utilities Commission Fifth Avenue Place, Fourth Floor, 425 First Street S.W. Calgary, Alberta T2P 3L8 Telephone: Fax: Website:

3 Alberta Utilities Commission Calgary, Alberta Blackspring Ridge Wind Power Plant Decision D Supplemental Post-Construction Comprehensive Proceeding Application A001 1 Decision summary 1. In this decision, the Alberta Utilities Commission was asked by EDF EN Canada Development Inc. (ECDI) to consider whether a post-construction comprehensive noise study complies with Rule 012: Noise Control. For the reasons outlined below, the Commission finds that the noise study demonstrates that ECDI is in compliance with the nighttime permissible sound level under representative conditions at receptor location SLM5. ECDI has satisfied the Commission order in Decision 3537-D Introduction and background 2. In Decision , 1 the Alberta Utilities Commission approved modifications to the Blackspring Ridge wind power plant and directed Greengate Power Corporation, on behalf of Blackspring Ridge IA Wind Project Ltd., to conduct a post-construction noise survey at receptor numbers 36, 3, 25, 18 and 21. The approved wind power plant consists of 166 Vestas V100 wind turbines, each rated at 1.8 megawatts (MW) for a total installed capability of 300 MW. During the daytime hours, the wind turbines are approved to operate in Mode 0 and during nighttime hours, most turbines operate in Mode 0 with 10 wind turbines operating in Mode 2, a reduced noise mode. The project is located approximately 30 kilometres north of the city of Lethbridge, Alberta, near Carmangay. 3. In Decision , 2 the Commission approved an application to transfer the power plant approvals to (ECDI). 4. On November 25, 2014, ECDI filed the post-construction comprehensive noise study. The noise study was conducted by ENVIRON International Corporation, on behalf of ECDI. On February 26, 2015, the Commission issued information requests to ECDI asking questions about the noise measurement methodology, and the results of the comprehensive noise study. ECDI responded to those information requests on March 13, In Decision 3537-D , 3 the Commission found daytime sound levels after isolation analysis at all receptor locations in the noise study demonstrated compliance with the daytime permissible sound level and the nighttime sound levels after isolation analysis demonstrated Decision : Greengate Power Corporation on behalf of Blackspring Ridge IA Wind Project Ltd. - Modifications to Blackspring Ridge Power Plant, Proceeding 2331, Application , January 8, Decision : - Name Change for the Holder of Blackspring Ridge Wind Power Plant and Blackspring Ridge 485S Substation, Proceeding 2640, Application , July 5, Decision 3537-D : Blackspring Ridge Wind Power Plant Post-Construction Comprehensive Noise Study, Proceeding 3537, Application , May 29, Decision D (March 2, 2016) 1

4 compliance at SLM1, SLM2, SLM3 and SLM4 (identified as receptor locations 36, 3, 25 and 21 in Decision ). However, the noise study did not demonstrate compliance with the nighttime sound levels after isolation analysis at SML5 (identified as receptor location 18 in Decision ). 6. Consequently, the Commission ordered ECDI to conduct a follow-up post-construction comprehensive noise study within a two-year period from the date of that decision, for receptor location SLM5, under representative conditions to verify that the facility complies with Rule 012 during nighttime conditions. 7. In response to Decision 3537-D , ECDI retained Ramboll Environ International Inc. (Ramboll Environ) to conduct the supplemental comprehensive noise study to fulfill the Commission order in Decision 3537-D The post-construction comprehensive noise study report for receptor location SLM5 was registered on December 22, 2015, as Application A001, Proceeding The noise study 9. Ramboll Environ conducted the supplemental comprehensive noise study (the noise study) over two consecutive nighttime periods between 10 p.m. on October 10, 2015, and 7 a.m. October 11, 2015, and between 10 p.m. on October 11, 2015, and 7 a.m. October 12, 2015, for receptor location SLM A Brüel & Kjaer (B&K) Model 2250 Type 1 sound level meter was utilized for noise monitoring. The microphone was set up on a tripod at a height of 1.5 metres and located 142 metres northwest of the dwelling. Ramboll Environ stated that the location of the noise meter at SLM5 was moved from the original study location to avoid the noise from wind rustling vegetation that dominates the acoustic environment in the vicinity of the house. The study stated that the alternative measurement location selected was beyond the area of influence of wind-blown vegetation noise but was considered representative of noise received at the dwelling from the nearest wind turbines (T111, T112 and T113). 11. The sound level meter was fitted with an acoustically neutral, all-weather windscreen to shield it from high levels of wind-induced noise, and the measured noise data were downloaded to a computer equipped with the B&K Measurement Partner Suite software for analysis. 12. The sound level meter was field calibrated before the start of monitoring and at the end of the measurement program, using a Larson Davis Model CAL200 calibrator. Both the sound level meter and calibrator were factory calibrated within the previous 12 months of the measurement period. 13. The sound level data were collected in one-second intervals, which included broadband L eq, L max and one-third and full octave band spectral data. The sound level meter was also set up to capture audio recordings. 14. Wind speed and direction were collected and reported in 10-minute average intervals from the Blackspring Ridge meteorological tower during the monitoring period. Wind speed data 2 Decision D (March 2, 2016)

5 collected at the 80-metre hub height of the nearest wind turbines (T111, T112 and T113) were averaged to derive an overall average wind speed for the three wind turbines. 15. Wind and meteorological data including wind speed, precipitation, temperature, pressure, and relative humidity were also collected approximately 12 metres east of the sound level meter using a Kestrel 4500 weather meter. 16. Ramboll Environ processed the wind speed data collected from the Blackspring Ridge meteorological tower and calculated these wind speeds to the standard height of 10 metres using the equations established from the International Electrotechnical Commission Standard IEC Acoustic noise measurement techniques. 17. Ramboll Environ stated that representative conditions were defined as operating conditions during which project turbines operated at a maximum sound power rating, with winds blowing from the southwest between 202 and 270 degrees and at calculated wind speeds of between six m/s and 10 m/s at a standard height of 10 metres. Ramboll Environ assumed that the wind direction data collected at the Blackspring Ridge meteorological tower was identical to the wind direction experienced at the standard height of 10 metres for the purposes of the noise study. Data collected that did not fit the wind speed and wind direction criteria were not analyzed in the noise study. Ramboll Environ stated that the electrical power output for the nearest wind turbines during representative conditions for T111 - a power generating capacity of 80 per cent, for T112 - a power generating capacity of 77 per cent, and for T113 - a power generating capacity of 95 per cent. 18. Ramboll Environ stated that the purpose of isolation analysis is to remove extraneous noise sources from measured sound level data that are collected during periods of representative metrological conditions. However, Ramboll Environ identified that the sound level was below the permissible sound level under representative conditions during the nighttime period of October 11 to 12. Ramboll Environ added that it reviewed the audio recordings and concluded that no extraneous sound events occurred during representative conditions. Consequently, isolation analysis was not conducted. 19. Ramboll Environ provided a statistical assessment of the required minimum number of valid samples in accordance with the method outlined in Appendix 9 of Rule 012. Ramboll Environ stated that for the nighttime period under representative conditions the number of collected samples exceeded the required minimum number of valid samples required Over the two nine-hour nighttime periods measured, Ramboll Environ determined that a total of 4.2 hours was found to meet the criteria for representative conditions. The representative data extended during the nighttime period on October 12, 2015, from the hours of 2:50 a.m. to 6:50 a.m. 21. Ramboll Environ stated that the noise impact assessment concluded that low frequency noise was not a concern for this project. Frequency data were measured using a single channel sound level meter set to a Z-weighting (unweighted) scale, and did not include a separate channel for A or C-weighting scale. Ramboll Environ reviewed the one-third octave noise levels in the 4 Exhibit X0001, Blackspring Ridge Wind Project Supplemental Post Construction Comprehensive Noise Study: SLM5 Noise Report November 2015, Section 4.5 Calculation of Minimum Number of Valid Samples. Decision D (March 2, 2016) 3

6 frequency range from 20 hertz (Hz) to 250 Hz measured at receptor location SLM5 and concluded that there were no tonal noise events, and consequently that low frequency noise is not a concern at the project site. 22. The results of the noise study are summarized in the table below. Summary of noise monitoring results, measured and adjusted Receptor location Average day and night sound level data All data, unadjusted Measurement period Duration Measured average sound level (Leq, dba) Average day and night sound level data representative conditions, unadjusted and adjusted Total cumulative duration of representative condition Measured average sound level (Leq, dba) Adjusted average sound level (Leq, dba) AUC limit (dba Leq) SLM5 October NIGHT 9 hrs (10 p.m. - 7 a.m.) 63.1 (a) 0 hrs n/a n/a 40 (a) (b) October NIGHT 9 hrs (10p.m. - 7 a.m.) hrs (b) 40 Representative conditions were not captured during this nighttime monitoring period and data was not analyzed. Wind speeds ranged from 13 m/s to 21 m/s at a height of 10 metres exceeding the performance standard of the wind screen, and often exceeding the cut-out speed of the wind turbines, resulting in time periods where there was no power generation. No adjustments were made to data collected during representative conditions 23. Ramboll Environ concluded that a total of minute average periods (4.2 hours) were found to meet the criteria for representative conditions during the nighttime period of October 11 to 12, 2015, and the results of the supplemental noise monitoring program indicate that during representative meteorological conditions, the wind power plant operates within the nighttime sound level criteria established by the AUC at receptor location SLM5. 4 Findings 24. The Commission observes that Section 4.1(2) of Rule 012 states: For the purpose of determining compliance with this rule, noise is measured at a distance of 15 metres (m) from the most impacted dwelling(s) in the direction of the facility, rather than at the property line of the land on which the dwelling is located. Other measurement locations may be used if it is physically impracticable or acoustically illogical to measure where specified. 25. Based on Ramboll Environ s description and the monitoring site photographs, and the placement of the microphones, the Commission finds that the monitoring location satisfies Section 4.1(2) of Rule The Commission further finds that the sound level meter and calibrator used in the noise study meet the minimum requirements of Rule 012. Also, the sound level meter was field calibrated both before and after the measurement period, in accordance with the rule. 4 Decision D (March 2, 2016)

7 27. In addition, the wind and weather monitoring and meteorological data collected from the meteorological tower and the ground level monitoring stations meet the requirements of Rule The Commission considers that the nearest wind turbines (T111 (power generating capacity of 80 per cent), T112 (power generating capacity of 77 per cent) and T113 (power generating capacity of 95 per cent)) to receptor location SLM5 were operating at representative operating conditions. The Commission further considers the operation of the nearest wind turbines, based on the calculated wind speeds of between six m/s and 10 m/s at a standard height of 10 metres, upwind from receptor location SLM5 and from the southwest direction, between 202 and 270 degrees, as being representative operating conditions for this noise study. For these reasons, the Commission accepts that the data captured during the period of monitoring from 10 p.m. on October 10, 2015 to 7 a.m. October 11, 2015, indicated that representative conditions were not present in that the wind speeds ranged from 13 m/s to 21 m/s at a height of 10 metres exceeding the performance standard of the wind screen, and often exceeding the cut-out speed of the wind turbines. However, the period of monitoring from 2:50 a.m. to 6:50 a.m. on October 12, 2015, yielded sufficient noise data (4.2 hours) under representative conditions for use in the analysis of compliance with Rule Further, the Commission is satisfied that the potential for low frequency noise is not a concern with the wind turbines because no tonal component was identified in the analysis of the one-third octave band data in the frequencies between the octave bands of 20 Hz and 250 Hz. 5 Decision 30. Based on the above reasons, the Commission finds the noise study demonstrates that nighttime sound levels under representative conditions are in compliance with the nighttime permissible sound level under Rule 012 at receptor location SLM Consequently, the Commission finds that ECDI has satisfied the Commission order in Decision 3537-D Dated on March 2, Alberta Utilities Commission (original signed by) Tudor Beattie, QC Commission Member Decision D (March 2, 2016) 5