Is it better for the environment to read your newspaper online?
slate.com
slate.com
Why? Because if you trace the cost of a product down to it's constituents almost every cost a product has is directly related to how much energy it takes to make it and it's parts. Even salary, because money spent on salary is based on prevailing wage, which itself is based on how much energy a person needs to live in their community.
Now obviously it's not perfect - in particular it doesn't include costs that are passed on to the public as a whole: most glaringly pollution of all types.
And possibly things that are paid for by taxes - although taxes raise the cost of the product and wages, so it's somewhat taken into account (as long as the product does not consume more than it's share of public funding).
But other than that it's very close.
So for the example here: if a paper costs $20 a month, but your computer costs $30 per month for service plus the cost of the electricity, plus the cost of the computer itself, it's a no brainer.
But you use your computer for other things too...
You want to know which car is better for the environment? (To make, not to run.) The cheaper one.
Part of the cost of a product is transportation. How much does it cost to transport something? The cost of the gas, plus the cost of the vehicle.
The cost of that vehicle? It's wages, plus the cost of transporting the parts, plus the cost of the metal, and the equipment used to make it.
The cost of metal? Energy used to power the machines that mine it, plus transportation, wages, and equipment.
Equipment? Wages, transportation, and base parts (plastic, metal, etc).
If you followed my thread, you see that every single cost eventually is the cost of fuel.
I haven't talked about wages yet. For the most part people spend all of their wages - what do they spend it on? Things. Things that have an environmental cost. Taking us back to where we started.
In an environment where wages are lower, it's because people spend less money on things, so those people are "better" for the environment.
I sometimes see environmentally friendly products that cost more than ordinary ones, and then I know they aren't actually that good for the environment.
There are two big holes here:
Pollution. Human misery.
A slave gets no wages (reducing the cost of the item) and also has almost no environmental cost. But the human misery is bad, and is not taken into account.
It's cheaper to make things if you don't care how much you pollute.
So the metric is not perfect, but it's very close (especially for comparing two products made in the same type of environment (pollution regulations, prevailing wages, etc)), and it's very available.