Is there a difference between b&w and color printing when the document is black and white anyway?

Is there a difference between b&w and color printing when the document is black and white anyway?

In some software we're writing, I'm wondering if I can force the printer to always print in black & white mode, and if that will speed up printing at all. The documents being printed are always black & white.

I know the user can change this setting himself, but since there's really no reason to ever print color, I just wondered if having the printer in color mode would try to blend the inks or something crazy rather than just using black ink only, and if that would cause any slowness.

The difference is that if you print in "colour" it may decide to mix the colour inks to produce the black/dark greys - especially if there's some "errors" in the document so that the red, green and blue values aren't quite equal.

By printing in black and white you will be saving on the colour inks/toners and yes it may well be faster (depending on the printer).

Yes, a colour printer may well add small amounts of colour to a print of a greyscale document. This can make blacks appear darker and more solid than pure black ink alone, due to the increased overall ink density and/or dots of different inks being laid out on slightly diffently different grids. I can imagine it being used to even out ink usage also.

This is going to be very dependent on the type of printer, its software and exact configuration, so would recommend testing.

Printing in black only is likely to save significant time over colour printing only where you're applying each colour in a separate pass and drying in between (most laser-type printers), not when you're applying them at the same time (most inkjet printers).