I've seen bluetooth consume almost 150mA on an idle connection on N810, that's about 500mW Usually reconnecting brings the power use down. Radiated power is pretty insignificant compared to total power used by the radio.. Also noticeable with the wlan, where you basically see no measurable difference in power use between 10 and 100mW settings, not even when sending huge files from N8x0.

Another comparison point, streaming music (screen off) my N810 uses a bit more power (on wlan) than my E75 on edge.