I find the idea of a personal carbon account/charge card so attractive. Even if you swiped it just when buying gasoline, electricity/gas, groceries, prepared food and long-distance travel: I think it would be so informative to see the difference in carbon emissions from all these different actions and purchases.
... these schemes have been proposed (and largely abandoned) in the past, with the long-term goal of having mandatory accounting and a trading system if you went over your annual allowance (cap-and-trade). But they might be more feasible and acceptable now.
And there have been attempts to add some nutrition-style labeling in stores (Tesco had a pilot program). But it would be especially valuable across different types of purchases, because it's the comparisons that people are so bad at.
and more current, you could get something like this just by analyzing your credit card transactions, right?
Doconomy provides a credit card that does this:
Oreoco suggests connecting your Mint transactions:
These depend on databases of carbon estimates for different kinds of products, but those are improving! including from Åland and UC Berkeley. Obviously they could be much more precise with product/service providers involved.
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