In a strict, it's-all-physics sense, yes, absolutely. In a practical, more-than-rounding-error sense, harder to say. 1 HP is about 746 watts.
The only one that affects MPG is temp. The more heat you need, the lower the MPG. Heat comes from the ICE, which is burning gas.
Ok so AC don’t do much? I was just curious if anything makes much difference. Love the 2020 L Eco I just got. But still figuring it out. MPG for 120 miles since I reset the meters the day I got few days ago it is 60 Something mpg. 60.7 or so. I know its estimate.
Everything else you mentioned is electrical, which power also comes from the engine, which is burning gas. How much power the cabin blower uses, I'm not sure. In my gen 3 it's on a 40 amp fuse, which suggests it might use as much as 30 amps or so on full blast; that's 360 watts, or around half a horsepower. But there are complicating factors, like if you turned the fan down, would you open the windows more? That can add wind resistance. If you add up the per-channel watts ratings on the sound system, you might get something that looks like a good fraction of a horsepower, but those are peak power ratings, and normally playing normal music will average much less power than that. The air conditioning compressor is variable power, can use anywhere from around 250 watts (third of a horsepower) to more like 3,000 watts (4 HP) when running flat out.
AC (Air Conditioning), the North American definition of AC, chilling the cabin air, imposes a significant, noticeable decrease in mpg.
The ac does cost mpg if it's hot outside, more power if it's humid, more if it's not on recirc and the compressor speed will ramp up some with the fan to keep superheat up to a safe level for the compressor. Hypermilers in the gen2 days when it was a thing would drive with their windows closed and ac off. They would also draft semis on the freeway and do irritating speed changes depending on the terrain.
depends on how much you like your mpg's. i focus on them like a video game. or in my case mpk (miles per kwh)
