Not to mention, most computers at the time didn't implement any kind of idle power savings. Running a flashy screensaver didn't use any more power than sitting at the desktop.
CRTs weren't that power hungry at all. E.g., an entire 8-bit computer from 1979 (Sharp Mz-80) is rated 45W, including the CPU, the entire PCB, and its 9 inch monitor. A 21 inch Trinitron CRT monitor is rated at 1.2A (this is less than a Raspberry Pi 3; there's no Watt rating on the label, but I recall it as about 30-35W). These are actual ratings from actual equipment, I have.
In fact, early LCD monitors were (much) more power hungry. E.g., a not that early Apple Cinema HD Display from 2007 is still rated 2.05A (65W) at 20 inch and 3.7A (90W) at 23 inch. Taking the weighted average, this is double the energy consumption of the 21 inch Trinitron CRT. A modern 24 inch M1 iMac is still in about the same range as this LCD, at about 80-85W (including the CPU and PCB).
Interesting. I gave away my old monster CRT so I cannot check.
I wonder if it would be possible to buy a modern 27" or larger CRT these days; I recall that the CRTs always looked better than the LCDs when LCDs first became popular.
Ok, I just looked up the specs for the most amazing CRT, I still have around, the ultra-flat, digital 17" Apple Studio Display. (It has no label of any kind that I could find.) This one clocks in at 115W, which is not so much in line with what I commented previously. Conversely, the LCD display of the same seies is rated at just 40W at 17". However, as digital connection standards moved on, the only computer you can hook these up to is the G4 Cube.
Generally, CRTs have a sweet point at about 17 or 19 inch. Anything bigger will come at a noticeably loss of quality (due to increasing alignment problems that come with color CRTs), even for the rather expensive ones. (Even a Trinitron is not that sharp at 19" as it is at 17". And I remember a particular 24" Radius display, where you couldn't tell dithered from solid colors.) I wouldn't go above 21", unless you're specialising in large layouts and insist on doing them on a CRT. ;-)
And, as far as I know, the production of commercial CRTs stopped in the 2000s. (But you can still get them, if you're Airbus or a similar manufacturer. [2]) However, for the mere mortals…
1.2A doesn't say much without knowing the voltage. If you're in the US and (this being a CRT monitor) it's running on a mains voltage of 120V, this would be 144 watts.
