does amp draw alot of power when volume is zero

Tswei,
Bel Canto uses B&O ICE modules. I don't know how many changes / upgrades are made.
However, the B&O data sheet says efficiency is in the 80%s at full power. Lower efficiency at lower powers. This is 'plug to speaker'
My ASP moduled PSAudio is cool even at high powers....but if I close the cabinet, it CAN get warm, even at the few paltry watts I draw under normal conditions.

Bel Canto publishes the idle power draw in the owners manual, as do many other manufacturers. Their current integrated (s300i) idles at 15 watts. I would leave it on 24/7.

Y'know, if you are concerned about power usage, its really a good idea to turn the stuff off when you are not using it.

I've been interested in solar power for a long time. I was shocked (hah! pun intended) to find out that the length of time it is on often plays a bigger role than how much power it draws.

It is a fact with audio that the hotter stuff often sounds better, as heat is being traded for lower distortion. So if you base a system entirely on heat generation, be prepared that the results may not be aligned with 'best sound for the money'.

Atmasphere,
For many years my ears have confirmed your insightful statement with very few exceptions.