OK, quite small then, brace yourself for some bad news...
I honestly cant see it making more than a few hundred watts on a reasonably windy day, and mostly much less than that. It is only equivalent in swept area to a horizontal axis turbine of ~1.5m diameter, and much less efficient- those bits inside the blades needed to get it started create a lot of drag. You would be very lucky if it was as much 25% efficient - the theoretical maximum is 59%, only approached by the very best aerofoil blades on horizontal axis turbines.
plugging the numbers into the standard formula:
P = 1/2 ρ A v^3 * efficiency (rho = air density)
= 0.5 X 1.2 (kg/m^3) * 1.82 * 10^3 (10m/s = 36km/hr wind)
Power = 1.09kW ie the amount of energy in the mass of air moving across the swept area.
X efficiency of say 0.25 (I suspect it is actually lower) = ~250W
What is it they claim, 1.5kW @10m/s?
I'll leave you to draw your own conclusions about the claimed output, but one explanation I can think of is that it must have some magic power that transcends the laws of physics
These sorts of output claims for wind generators are unfortunately all too common.
It is possible you might see 1.5kW in a wind around 70km/hr or more, if there is minimal turbulence, but I'm not sure how safe it would be in such a strong wind.