There's also the issue of motivation and inspiration. There are days where I can easily take a hundred or so shots (though I can only submit 1 for that day ) and there are days where it's a struggle to even take one.
I have the same issue. But I submit one a day and the other 100 I cull and consider for the "next" day. When and if I cannot find anything else or when I am certain that the conditions are what I want, I have shots in reserve that I have taken before. And often, based on different conditions, the second shot is almost entirely a different shot. For example... there is a shot of the Sterling Cloisters Courtyard that when taken at the time I want to take it, simply has too much flare and bloom. So I have set it aside for a nice overcast day or perhaps an afternoon when there will be a beautiful sunset. Last day?
Unless you are geographically in a very different place, consider shots you already took but did not submit as scouting shots. Look at them and critique them. See how you might do them better, then shoot them at a later time for submission.
Some may say this is not "art." I wholeheartedly disagree. Previsualization is an important technique in photography. The definition is something like: "Previsualization also known as pre-rendering, preview or wireframe windows is a function to visualise complex scenes in movie before filming. It is also a concept in still photography."
Borrowing from film and theater I refer to this as "blocking." Borrowing from a blog I have been reading:
"The simple lesson of previsualization - that is as applicable today as when Ansel Adams was capturing his spectacular images of Yosemite National Park - is that while one might get lucky, and capture a fine image, the far more likely result of approaching a subject without an idea already in mind is disappointment... Fine art does not just happen; it requires a (sometimes prodigiously willful) act of inspired, participatory creation. The artist must be a willing and active participant in all of the steps leading up to the image's final (typically print) form; including the act of capture." Please see: Tao of Photography: Previsualization ...or... Why Ansel Adams Could Never be Happy With a Point & Shoot Camera
Anyway, I am probably making the mistake of anticipating arguments folks might make against what I am saying... if this idea is acceptable great. If not, that's fine too. As for me, I have shot the same scene perhaps as often as three or even four times in the course of this exercise. I do not go out looking for the one shot. I go out looking for three. If I get even two every day, I basically have an entire week of shots to fall back on. My one rule is that I have to go back and shoot it if I would propose to use it for that day. This has been what has kept me comfortably ahead of the "shot deficit" that I would otherwise be running. At the moment I have at least seven ideas that are based on previously shot ("blocked") shots and a few vague unproven ideas that still need to be wireframed.