Had some fun with this yesterday: it's from our blog on backpackthesierra.com
Is there a mathematical solution to the challenge of ultralight backpacking? It seems that an engineer would be able to develop an equation that could be used to fine tune our equipment. It would have to address a number of variables. I am not an engineer, nor do I play one on TV, but I did have some fun working through this problem:
W = the weight of your pack when you leave the trailhead. The goal is to manipulate the other variables to achieve a very low value for W. Lighter is better
P = the price you have to pay for your equipment, in dollars. Please convert from Euros, Rubles, etc. if required.
And somehow our equation needs to reflect that as W is reduced, P usually increases.
In fact, as W approaches zero, P probably arrives close to infinity—or at least beyond the reach of normal people. In other words: Priceless. Ouch.
Instead, let’s set up the equation to reward people who do this lightly and CHEAP.
So with all that in mind:
W = Weight in number of pounds you carry. Note that this will NOT be what you WANT to carry which will always be N-1 (where N = # ounces you are carrying).
C = $800—the rough price we paid for our backpacking outfit. You will have to use your own numbers here to see how you compare.
P = the Price you must pay for the gear (in dollars, pesos, rubles, etc.) per pound
So the final equation reads like this:
P = C/W
Do you want to buy a new tent? What if the new tent weights three pounds?
P= 800/3 = $266.67.
Is that a good deal? Let’s compare that to staying with your old, four pound tent:
P= 800/4 = $200.00
Is paying $66.67 worth it? Maybe. Most of us would agree that paying $20 would be worth it, if we could save a pound on our pack weight. Many of us would pay a lot more for that!
What about a new 1.5 pound tent?
P= 800/1.5 = $533.33
That makes some lightweight gear seem like a screaming deal!
Now let’s look at my own list, bearing in mind that we are NOT ultralighters, and that my wife and I certainly believe in some creature comforts. So we carry about fourteen pounds each, not including water and food.
P = 775/14 = $57.26 cost per item per pound.
So I am presenting that as the BTS (Backpack the Sierra) constant. Let’s round it off to a nice round $60 per pound.
So how does your pack stack up? The real goal here isn’t to get the pack weight to zero—it’s to see how cost effective your kit is. Do you get by with lower cost equipment, but stuff that might weigh a little more? Or do you go for the ultimate lightweight gear, even if it costs you more?
And how do those answers fit into the equation? I would assume that other regions, which require more or less equipment, have somewhat different answers. Our own answers for winter camping would be like this:
P = 1000/18 = 55.55. That’s pretty dang close to the BTS constant!