These are the 2 CO2 bottles that I use for injecting the gas into my planted fishtank. They contain water, about a half cup of sugar, and bread yeast. I have to so I can alternate which one I change every weekend and get a more even flow of carbon dioxide into the tank. I have the little orange bread tag to tell me what one I changed last. Each bottle is good for about 2 weeks, but they peter out nearer the end, so it works out well to have both of them going. I used the juice bottles because I read somewhere that people have had their pumps suck the sugar water right out of soda bottles, collapsing the thinner plastic. 
Do you realize that water+sugar+yeast makes moonshine or ethanol? You could distill the mixture after the 2 weeks and put up to 10% into a gasoline vehicle.
It’s pretty cool! http://danfolkes.com
Yes, but I would need to use something in the order of 10 gallons of sugar to make a gallon of ethanol.
Considering I am using less then a cup a week, this could take a while.
Anyhow, the still I would need is regulated by the ATF, and I would need to apply for a permit from them. They want the still to be in a separate building from your residence, and I live in an apartment – no chance of that happening.
Anyway, buy the time I had saved up enough by-product to make it worth the time to run it through a still, it would have all turned to vinegar anyhow.
You really don’t want to pour ethanol you’ve distilled into your gas tank. Unless you have a really spectacular fractionating column and you manage to get 95+% ethanol, there is going to be enough water left to do engine damage.
It would be fine for drinking purposes, but at a cup of sugar a week, hardly worthwhile. It takes about 4 pounds of sugar to make a liter of 80 proof moonshine.