"Alot of light and heat can get reflected back"
To be clear, I'm only talking about light that gets inside the house. Not the sun light reflected off the exterior glass.
What I'm thinking about is a normal room with a mix of dark and light objects inside.
Yes, I know that if everything in the room was painted black, it would not have much light lost back out the windows..
But, in a normal room it seems like (once inside) only a small amount of light bounces back outdoors.
My guess is about 10%..
I could be way off.
If it were a lot light coming out, looking into a window from the outdoors, would be almost like looking at the sun..
Like if your room was covered with mirrors, much of the light would just bounce back outdoors.
So, my thinking is, if you have 90% of your light bouncing inside the normal room,
isn't it going to get converted into heat? It can't just bounce around all day..
My point is, whatever comes in the window (and stays) is all you get..
It's going to convert into heat..
If it's 90 watts, it can only convert to 307 BTUh.. No matter the colors of the room.