Depending on tire inflation I have to be going ~26 mph to be putting out 220-230 watts on my TACX rollers IIRC. I look and see if I have some power files from the rollers to verify...
mm.. ~ 42 km/h at 220-230 W - this amchine is pretty soft.. - if you find your files it'll be interesting to see - so it does NOT simulate a flat road/zero wind conditions as I imagined..