As part of a prior agreement with the North Carolina Division of Air Quality (NCDAQ), Duke Energy Corporation was required to establish an on-site ambient monitoring program at its Allen Steam Station west of Charlotte, North Carolina. Allen Steam Station is a base-load coal-fired electrical generating station. The ambient monitoring program included three SO2 monitors, and one 10-meter meteorological tower (ALN). This data, when combined with other nearby wind data, provided a unique opportunity to make an evaluation of the representativeness of the ALN wind speed data. This paper is the first of a series which examines the relationship of three wind measuring sites in the Charlotte, NC area:

• Allen Steam Station on-site (ALN)

• Charlotte National Weather Service station (CLT)

• Duke Energy Corporation’s Catawba Nuclear Station (CNS)

The data record examined for all three sites is from April 1, 2000 to March 31, 2001.

This paper specifically addresses a comparison of wind speeds measured and recorded at CLT and CNS. The interest with this comparison is that the two sites, while physically close, use completely different wind measuring systems. CLT is 22 km north northeast of CNS. Ten-meter level winds only were used, although CNS also has 60-meter level wind data. The CNS meteorological tower was equipped and maintenanced to meet or exceed PSD meteorological monitoring requirements, and hourly averaged winds are recorded. CLT uses standard National Weather Service quality wind instruments and 1 minute averaged winds from a few minutes before the hour are recorded. The threshold wind speed at CNS is 0.5 mph; for CLT the threshold is about 3 mph. The analysis will show graphically that the average wind speed patterns are very similar, by magnitude and direction, in spite of the differences in measurement systems. One implication of this finding is that, on average, a nearby NWS is equivalent to an onsite wind measurement program.