On Jul 12, 1:09*pm, kansascats wrote:
I plugged my window AC into a "killawatt". *It was running 900 watts,
then the past few days it's been climbing to 1000, then 1100, even
1200 as the day wears on -- and the sun beats down on the unit to the
west side.

Suppose shading this could make a big (300 w) difference?

Somewhat, but don't forget even if shaded, the air temperature around
the unit is rising even if the unit is not in direct sunlight.