Have you ever wondered which of two options is the most frugal? That's when it's time for a quick comparison, or as I like to call it, a thrifty throwdown.
Take toilet tissue, for instance. Which is more economical - single or double-ply? That probably depends on your household's habits. For me it's a toss-up. I pretty much use the same amount either way. If you have a family member that likes to grab the roll and wrap and wrap and wrap great wads of the stuff around his hand, then you will probably find the single-ply to be cheaper. If you have a CVS in your area, I find those $5 off $20 coupons they sometimes let you print out with your card to be great for stocking up on CVS brand toilet tissue when it's on sale. It's very cheap this way.
What about cloth vs. paper napkins? I'd say it comes firmly down on the side of cloth napkins. I have been using the same set of handmade cloth napkins (one of the best Christmas gifts I ever received) for about fifteen years now. I would have had to buy an awful lot of paper napkins in that time, not to mention the environmental impact of using all that paper. What about the cost of laundering the cloth napkins? I find they take up very little space in a load, so it's no trouble just to throw them in with my normal loads. If your family are not messy eaters, they can be used several times before being washed. Use napkin rings to keep track of whose napkin is whose.
Consider bottled water vs. a reusable bottle and a filter system. You would have to figure out how much filtered water you drink, both at home and and away. Then you would need to look at how much bottled water sells for (don't forget the bottle deposit, which you will get back if you return them to a recycling center), the price of the filter system and replacement filters, and how much water you can filter with them. I can get the filters pretty cheap on sale, with a coupon. For me, the home system and reusable bottle makes a lot more sense, although I still can't get my significant other to use a reusable bottle. He says he will just lose it. So, I make sure I at least recycle all his bottles. Economics aside, it takes energy to recycle all those bottles, even if they do all get recycled. For most people, the reusable bottle and filter system will be the better choice.
Should you boil water for tea and coffee on the stove, or heat it in the microwave? That depends on whether your stove is gas or electric, and how much you pay per gas therm or kilowatt. This information can be found on your bill. You would need to calculate how long it takes to boil the water, and how much energy your stove or microwave uses in this time. Even easier, would be to do it one way the first month, and the other way the next month, and compare your bills. You would have to make sure all your other energy usage was about the same as usual to get an accurate comparison.
Is it cheaper to use regular light bulbs, or the new CFL bulbs? The regular bulbs are a lot cheaper to buy initially, but the CFL bulbs last a lot longer. They also use a lot less energy. The only time the CFL bulbs are not cheaper to operate is if you have them somewhere where you turn the light off and on constantly. Then they wear out a lot quicker, and the initial cost of purchasing them will not be recouped in energy savings.
During the course of your day, when you think of something that can be done more than one way, take the time to do a quick frugal faceoff. Once you've done the calculations, you will save each time you perform the activity in the most efficient way. Unless the factors involved change significantly, you only have to do the math once. Save all of us some brain strain, and post your own able analyses here.