(finally figured out the quote, kinda)
...I think you're forgetting about the lights part. Some of that "energy" is converted to light, some wasted off as heat.
Example:
Lamp #1 we feed 100 true watts. We get equivalent of 30% energy conversion to light, we are left with 70% of our energy as "waste" or heat.
Lamp #2 we feed 100 true watts. We get equivalent of 35% energy conversion to light, we are left with 65% of our energy as "waste" or heat.
Lamp #1 =/= Lamp #2
Light emitted Lamp #1 =/= Light emitted Lamp #2
Heat dissipated by Lamp #1 =/= Heat dissipated by Lamp #2
From the same wiki link provided:
"minus the amount of
work done by the system on its surroundings"