We have had very little hot weather where I live, so most of the rides are done 15-20’C, which feel a lot cooler than the temperature for my turbo rides. I generally sweat very little on these rides, take 2 x 750ml drinks and have to stop for a nature break at some point, which makes me think that I’m not really suffering with dehydration.
The power meter is a garmin vector 2S single sided pedal system, which I also use for my turbo rides.