The project apparently got started on October 9, or at least the display indicated that the cumulative production was taken starting from that date. Since inception, the Proven has produced 538 kWh, the Skystream 344 kWh, the Aerovironment machines 67 kWh, the Windspire 57 kWh, and the Swift brings up the rear at 2.4kWh. The MOS display also calculates capacity factor, which ranges from a high of 9.2% for the Skystream to 4.6% for the Proven, to 2.4% for the Windspire, 0.68% for the Aerovironment machines, and 0.08% for the Swift. Capacity factor is the amount of energy actually produced in a given site, as compared to what the turbine would produce if it operated continuously at its nameplate power rating – values of 20-40% are the norm for commercial installations, with many homeowner installations lower than that. The MOS also calculates a “relative production” for each turbine, which I gather to be the actual production as a percentage of manufacturer’s claimed energy production for a site with the average windspeed at the Boston MOS. This ranges from 61% for the Skystream down to 0.5% for the Swift.
This is a very poor site for a small wind turbine (as usual) but the data is real enough. Reality is in short supply in this industry. Of course there are many arguments for caution in using this sort of data. But beggars can’t be choosers as they say, and the installation was done on a rooftop, where many of (the worst of) these machines are supposed to be sited!