Ann: Carnegie breaks ground on 10MW Northam Solar Farm, page-23

Yes, that is the conundrum!

Perhaps 240 KW is the maximum theoretical output in perfect (large) wave conditions and that 40KW was what was achieved in the wave conditions at the time of the CETO 5 test (which were presumably more "typical").

This presentation contains one version of the '40KW' graph - in this case the axis is labelled "Cumulative Power", the horizontal axis is time in seconds. Not sure what "Cumulative Power" means.

Would certainly be a good question to ask CCE for clarification!