which is marginally higher frequency than what would be considered representative of expected open ocean conditions. Thus the waves on the whole tend to be steeper than expected open ocean conditions. The seas were generally much more directionally spread than would be expected in open oceans (with a spreading index typically between 1 and 2), and with stronger currents than would be typical for a candidate utility WEC location (FSE currents up to 2 m/s). All things considered, the deployment location was a good choice, offering many seas in the operational range and several in the design range. WEC and environmental data was collected for more than 25,000 trials of 512 s duration. After quality control of sea state data and WEC PTO data, roughly 16,500 trials remained for consideration. WEC performance was characterized primarily using the Relative Capture Width (RCW). Performance was shown to correlate with six parameters characterizing either the WEC or metocean conditions: energy period, significant wave height, wave heading, PTO damping, Unidirectivity Index, and fitQ (a parameter describing the spectral shape). The strongest correlation is with the frequency content of the incident waves. In general the observed frequencies had been Doppler shifted by the pervasive tidal currents and as such the observed, rather than intrinsic, spectrum was used to calculate the energy period. Performance declined noticeably with increasing energy period. Though not as drastic, wave energy capture efficiency also declined with increasing wave heights. As expected, performance was best for head seas. This trend, however, flattened significantly with increasing energy period. The effect of PTO damping is harder to quantify, primarily because the testing of significantly different damping cases was fairly limited. That being said, performance dropped noticeably when very heavy damping was applied. Although the incident seas were in general extremely short-crested (i.e. heavily spread directionally), the positive correlation of performance with increasing Unidirectivity (i.e. long-crestedness) is clear. Finally, performance was shown to be negatively correlated with fitQ, implying that performance is generally improved when the incident wave spectrum conforms to JONSWAP shape.
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