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36 <br /> 1 single Solaron 500 inverter is about 68 dB at 1 meter (= 3.28 feet). Importantly, no noise data <br /> 2 were submitted for the site's step-up transformer(s). <br /> 3 <br /> 4 2. Why the Inverter Noise Data in the Application is Incorrect. <br /> 5 A. In contradiction to the aerial diagram showing nine inverter units scattered broadly across the <br /> 6 site, the Site Plan depicts three 1500 kW triple inverter "stations", each presumably consisting of <br /> 7 three 500 kW inverter units (and, also presumably, at least one step-up transformer). No noise <br /> 8 data were provided by the applicants for this type of triple inverter station configuration, and no <br /> 9 information was provided regarding noise from the step-up transformers that are associated with <br /> 10 them. <br /> 11 <br /> 12 In the absence of information from Binks regarding the exact inverter/transformer configuration, <br /> 13 I made the assumption that each station comprises three Solaron 500 inverters (ignoring any <br /> 14 potential contribution of transformer noise) and estimated the combined noise produced by each <br /> 15 inverter station. The triple inverter station noise level can be estimated by summing the noise <br /> 16 from each inverter using the calculation shown in Appendix I. This calculation shows that almost <br /> 17 ten times as much sound pressure and twice as much perceived noise (77.54 dB vs. 68 dB at 1 <br /> 18 meter) will be produced by a triple inverter station compared to a single inverter unit. 77.54 dB <br /> 19 may well be an underestimate of the total noise produced, since the applicants provided no data <br /> 20 on step-up transformer type, location or noise, which should be added to the inverter noise <br /> 21 figure. <br /> 22 <br /> 23 B. The distance from the nearest triple inverter station to an adjacent property is much shorter <br /> 24 on the applicant's Site Plan versus what is depicted on their aerial diagram. The triple inverter <br /> 25 station closest to Cascade Drive on the Site Plan is approximately 104 feet from the <br /> 26 Petranka/Gewalt Property (#15 BI A Sec 1 Falls of New Hope Estates). This is in contrast to the <br /> 27 distances shown the aerial diagram, where the shortest distance from a single inverter to the <br /> 28 Cantwell/Wegman Property is ca. 201 feet. Since sound intensity increases exponentially with <br /> 29 decreasing distance to the source, these inaccuracies in distances in the Application are very <br /> 30 important. <br /> 31 <br /> 32 3. What is the Combined Effect of Noisier Inverter Stations Being Sited Closer to <br /> 33 Adjacent Properties than is Depicted in the Binks Application?The closest triple inverter <br /> 34 station shown on the Site Plan is located across from the intersection of Falls Drive and <br /> 35 Cascade Drive. The distance from that inverter station to the closest property line <br /> 36 (Petranka/Gewalt) along Cascade Drive was estimated using the scale on the Site Plan. That <br /> 37 distance is approximately 104 feet. The following Table summarizes the noise levels expected <br /> 38 at the Petranka/Gewalt property line based on the revised noise calculations and triple inverter <br /> 39 distances contained in this document. <br /> 40 <br /> Distance (Feet) Distance (meters) Sound Level (dB) <br /> 3.28 1 77.54 <br /> 6.56 2 71.54 <br /> 13.12 4 65.54 <br /> 26.25 8 59.54 <br /> 52.49 16 53.54 <br /> 104.99 32 47.54 <br /> 209.97 64 41.54 <br /> 419.95 128 35.54 <br /> 839.90 256 29.54 <br />