Thinking (too) hard about carbon offsets
A few years ago, my sister stumbled on one of those “bundled” carbon offsets with a flight purchase. It was well under 10% of the flight price. “That’s so cheap – if that’s all it takes to fix up emissions, what’s the problem?”
And then today:
“A friend of mine flies a lot, mostly for fun, and thinks carbon offsets are “21st century snake oil”. What do you think?”Paul
Once was random question, but two’s a raucous crowd of people craving answers! (No, seriously, people ask Sustainist this all the time; that’s the kind of reputation he’s built.)
There are two basic problems to worry about with offsets: quality, and price – or moral equivalency.
Quality
(Or, how to not get ripped off with do-nothing offsets.)
There are a bunch of different aspects to quality. Some offset companies plant trees and then sell the expected 80-year lifespan of the tree’s offsets right away – even though the tree may well burn down, or turn into a subdivision in 20 years ‘cause the offsetter went belly-up. Only a diligent reading of what you’re buying – and maybe regulations, someday – will prevent this.
And there’s double-counting: how do you know how many different companies are claiming “emissions reductions” from one methane-burning project? (Methane is a byproduct of decomposition of garbage and poopmanure. It’s a potent but relatively short-lived greenhouse gas; capturing and burning it leaves only CO2 and oxygen, with about a 20x decrease in overall greenhouse effect, and even more if you actually do something useful with the energy from burning, displacing other energy production.) There’s a voluntary registry, but mostly you have to find some kind of trust. Sustainist recommends blind faith; most of these companies are genuinely trying to do good.
Then there’s additionality. This is the big one that I think most people think of when they call offsets “snake oil”. Are the offsets that you’re paying for additional to what would have happened anyway? There are different tests to figure out if something is additional: a regulatory test (did they have to do it by law?), a finance test (did it make enough money to pay for itself without extra funds?), a timing test (does the timing of the project make sense with the idea of offsetting? Or was it already well under way?).
But in the end, you have to read about the offsets you’re buying. That sucks; find a company you like and stick with them. I’ve used Terrapass, and generally appreciate their transparency about their projects; they even answered a question I had one time! (And no, I have no other affiliation with them than an active customer. It sucks that we live in such a world.)
Morality
Great! You’ve bought awesome offsets. Who cares?
My sister was right: if it only cost 15USD/tonne for offsets, we’d be golden. And that’s what you pay on the retail, voluntary market today – what’s up?
First, you’re probably only offsetting certain big visible things: your heating, your flying, your car. Those are big, but they’re still not dominant. Per capita emissions in western countries range around 7 to 20 tonnes per person. But Qatar tops the list, along with many other oil-producing countries; most of those emissions actually “belong” to other countries. (Here’s one visualization of “traded” emissions.) So you probably need to buy something like 15 to 30 tonnes per year, but that might still be viable.
But, of course, these offset companies are business, and they’re finding the cheapest (“marginal”) sources of emissions to offset. For the long haul, estimates very widely from “it’ll save us money in the end” to “oh my god we’ll be living in grass huts”. But if you want to make some kind of moral equivalency – if you really want to purchase an indulgence – I think you need to do it at the high end of what we think we might have to pay. That means, per tonne of CO2 avoided, more like 50USD or 100USD[1] than 15USD. Do the math, and now you’re talking about a couple of grand a year.
So now, Sustainist blesses you: Go forth and spend a small fortune on high-quality additional offsets, and indulge in a nice trans-atlantic flight.
(Seriously though, flying weighs heavily and I don’t take this question lightly. Nothing offsets emissions like not emitting them!)
[1] http://sapiens.revues.org/index793.html is a very dense but fairly readable summary of a bunch of work. It basically concludes that there’s no good conclusion, though.
