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If replacing the window is an option, then Pella Designer Series windows are available with triple-pane glass and removable miniblinds or shades inside a glass hinged panel. The blinds or shades don't get dirty and the extra glass panel makes the windows very energy-efficient. However, the frame size of the fixed window or large awning would have to be 59 inches or less to be ordered with a blind or shade. The maximun width on a casement would be 35 inches. Maximum height would be 73 inch frame size on either.
If your window treatment turns out to be expensive, compare the cost to replacing the windows themselves.
The most often recommended window covering for efficiency is a cellular shade.
Please note that as you keep more of the interior heat from reaching the interior window surface, the potential for condensation will go up with that reduction in heat exposure as a result of the window's lower surface temperature.