Homemade Detergent, How Much Do You Save and is it Worth It?

In August, I made my own detergent for the first time.  After lobbing half a bucket of kitty litter's worth of detergent into my washing machine, I ran out in the middle of November.  I had every intention of making more detergent that weekend, but then I got lazy.  And then XTRA detergent was on sale for $1.99 a bottle, so I decided to try it.  If you haven't see it at the store, it looks like this:



As I still had half the box of washing soda left over from the last batch, though, I figured I had to make at least one more batch.  This time I decided to try Recipe #9, which is a dry recipe, in the hopes that it would dissolve (I have a front load washer, with a little cup for detergent, but the first recipe did not dissolve in it, I had to chunk it directly in).  I made a 1/8 sized batch where I pretty much followed her recipe (using Ivory rather than Fels-Naptha because I can buy the former locally), but didn't have any baking soda, so I omitted it, and it dissolved really well.  Then I bought some baking soda, and added it in, and there seemed to be more residue left behind.  So I only put two cups of baking soda into the 1/2 recipe batch I made to use up all the rest of the washing soda.

Cost: Washing Soda - $4.23, Borax - $3.00, Baking Soda - $0.58, Ivory Soap - $1.19   Total = $9

I'm using 1/8 cup per load, so figure about 128 loads, for a minuscule amount more than  $0.07 per load.  This is way cheaper than my last batch, where I estimated that each load cost about $0.16, mostly because Ivory is cheaper than Irish Spring, which I used last time because it was what was lying around and because I can't find washing soda locally, so it is my most expensive ingredient, and there's a smaller proportion of it in this recipe.

For comparison, the XTRA detergent claims 28 loads (although really it's probably more like 25 because it is hard to measure exactly), and cost 1.99 + tax = $2.15, so each load costs me slightly more than $0.075.  But it was on sale for 1/2 off, so each load would usually cost (3.99 + tax = $4.31 / 28 =) slightly more than $0.15 per load.  That's 2.5 times as much.  Figure I do six loads of laundry a week (I work on a farm), this homemade detergent is $21.93 annually, XTRA on sale is $23.96 annually, XTRA regular price is $48.03 annually, last time's detergent is $49.92 a year, and Arm and Hammer (what I bought at the beginning of the detergent odyssey) is $62.70 annually.  So I am saving $40.77 a year vs unthinking laundry purchases, but only $2.03 vs bargain detergent on sale.

This doesn't count the Major Frugal Fail I made with regards to the container. I wanted something smaller than the kitty litter box I used last time,so I went to Bed, Bath, and Beyond and bought a cute little airtight container with a pop-off top, which cost me $7.77, making the real cost of each load $0.13 each unless I can amortize the container over multiple batches of detergent.  Some times I think that Debt Ninja is right to say that men are more naturally frugal than women; I bet most men would have used whatever container was handy.
 
So the real question is - is it worth it?  As far as quality goes, I could not discern a difference between the last batch and a commercial detergent, and my three test loads seem to indicate that the new batch will perform equally well.  So then it's just a matter of how much time it takes, which is probably an hour or so per batch.  It takes about 5 minutes to mix up the dry batch; the rest of the time is spent tracking down and purchasing the ingredients.  I'll probably need to make about three batches a year, so that's about three hours, paying me $13.59 an hour to make my own detergent verses unthinkingly buying the brand I always use or $8.70 an hour versus buying bargain laundry detergent.  This is worth it to me.  (Remember that saving money this way is like "earning" money tax free, as goods are paid for using hard-earned after tax dollars.  So I am calculating based on what I consider my time worth after taxes are deducted).

I could also stock up on bargain laundry detergent when it goes on sale and save about the same amount every year.  I am not sure how much time this would take; it would depend on the frequency that bargain detergent goes on sale.  My impression is that it goes on sale pretty regularly (this week, for instance, Walgreens brand detergent is on sale for $0.07 per load in my area), so I'm guessing this could also be done in about three hours a year, or less if I had enough storage space to buy it just once or twice annually.

So I just have to decide if I'd rather spend my time shopping for deals on detergent or making it myself.  The one thing I am sure of is that I'm not going to pick up premium detergent unthinkingly again.  Which would you prefer?