Wednesday, February 14, 2007

Carbon offsets: good, bad or ugly?

Yesterday I talked about CheatNeutral: a spoof website that offers people the ability to compensate for their infidelity by investing in projects that will help other people stay faithful. Their message is that that makes about as much sense as offsetting carbon emissions.

The fundamental difference of course is that greenhouse gas emissions have the same effect no matter where or how they’re emitted (actually, there are some exceptions – eg, carbon dioxide emitted at high altitudes by planes seems to have more of an effect – but by and large this is true). It makes no difference to the climate whether I emit a tonne of carbon dioxide by driving my car in Sydney or if you emit a tonne of carbon dioxide by having a bonfire in Canada.

Anyway, let’s look at the three criticisms I discussed yesterday that are levelled at the idea of greenhouse offsets.

Carbon offsets are not necessarily effective.
If you drive somewhere, you instantly pump a measurable amount of greenhouse gases into the atmosphere. If you pay a company to invest in a renewable project or plant some trees, how do you really know how much that reduces emissions by?

This is a very valid concern, but it’s not in my mind an argument against offsetting altogether. It just means you need to be careful how you do it. You need methods to measure, verify and audit reductions and methods to deal with uncertainty.

Let’s take an example. Say I want to offset some of my emissions by providing funds to a company that will plant trees to sequester (another great word!) carbon dioxide. Sequester is the cool way to say ‘suck out of the atmosphere’. But there are some issues with this:

  • I’m pumping gases into the atmosphere now but the trees will suck it out over a number of years.

  • What happens if the trees are destroyed in a bushfire or by disease and the carbon dioxide they’ve sequestered is released back into the atmosphere?

  • The rate at which they sequester carbon dioxide is uncertain: it depends, for example, on the weather over the coming years.
These are certainly real issues but there are ways to deal with them. We can account very conservatively: if we know that the trees will suck up between 1 and 2 tonnes of CO2 a year but we can’t be more precise than that, well, we only count it as 1 tonne per year. We can further reduce the emissions we count by the risk of fire, etc. And, we can insure the plantation, so that if it does burn down we can replant it immediately and perhaps also buy some offsets from other projects to make up for the lost time. We can have the offsets independently verified and audited.

And there are various ways we can deal with the timing issues. A simple way, for example, is to count / sell only the emissions that are reduced that year. So, we plant our trees and year one, we estimate they sequester 1-2 tonnes of CO2, so that year we sell 1 tonne’s worth of offsets. Year 2, we estimate they sequester a little more – 1.2 – 2 tonnes, so we sell 1.2 tonnes worth, and so on. Another way is to count up the estimated reductions over the life of the tree and sell them all up-front - but discount their value on the basis that they will only come online gradually and so do not fully compensate for emissions that are all happening in year one.

The devil is in the detail and we need to be vigilant to ensure we get what we pay for, but this is hardly unique to carbon offsets or a reason to reject them as being able to make a valid contribution to dealing with the problem.

Carbon offsets are immoral because they allow people to pay someone else to deal with the problem, rather than taking responsibility for the problem themselves.

I accept that this is a concern for some people; it’s not really a concern for me. I’m interested in seeing that the problem is dealt with. I don’t really care if Bill Gates takes two hour showers and flies around the world in a private jet which he then washes in French champagne and dries with irrigated-Egyptian-cotton bath towels that he then throws away, if he decides to make up for that by funding a solar power plant that will allow a dirty coal power plant to be closed down. I know many readers will feel differently though.

Flowing on from 1 and 2, carbon offsets interfere with other effective measures to combat climate change because they allow people to distance themselves from the problem and so they reduce the pressure on individuals, governments, businesses and communities to take measures that actually will have a real impact.

This is the criticism that resonates most with me. If it’s true that offsets are not sufficiently scrutinised so that they don’t truly offset the emissions they claim to, but we think they are and so we leave it to offsets to deal with the problem – well, that is a problem.

But I don’t really think that offsets do have this effect. I’ve heard similar kinds of arguments about efficient hybrid vehicles like the Prius: they won’t have any positive effect because people will then think that all they have to do to be good green citizens is buy a hybrid. In fact, I think the research shows that people who are buying hybrids and offsets are people who take environmental issues including climate change seriously, and are taking a whole lot of measures in their lives to try and make things better. Rather than encouraging people to switch off and leave it to offsets to deal with the problem, I’m prepared to believe that offset schemes engage people and actually encourage them to take steps to reduce their personal emissions as well.

But enough from me – what do you think?


pedaller said...

Let's assume that 2,000 people a day take a plane trip equivalent to the distance between Australia and Europe. That's about 11,000 tonnes of carbon dioxide released every day.
You'd have to plant about 40,000 trees every day, or 1,667 every hour to offset those emissions alone. That's 14.42 MILLION trees every year. In Australia alone we'd have to plant about 10 MILLION trees every year just to offset the carbon emissions from cars. Assuming 1 tree occupies 1 metre square that's about 24 square kilometres of new trees every year!
This would equate to hundreds, if not thousands, of square kilometres of new tree plantings every year to offset global emissions.
My concerns about tree planting to offset emissions is that it is a totally impractical solution. A bit like towing icebergs from Antarctica to solve Sydney's water shortage.

laura said...

Agreed on points 1 & 2; I do have an issue with 3, though. An example; I read about a carbon neutral company who were, among other things, offsetting emissions by paying a company to capture methane emissions from a mine. This is ineffective because it's likely to discourage the mine operators from introducing measures which reduce the methane emissions in the first place.
So I suppose the potential for carbon offsets to interfere with other effective measures is something that may need to be dealt with on a case-by-case basis.

Grant said...

I think offsets have their place, but at the end of the chain - Reduce, Renew, Offset is a kind of mantra that I like, that presents a kind of hierarchy.

For example - I own a car. First we have an efficient car (a 1.3l engine). Secondly, we don't use it very often - only when there's a true need (we walk a lot!). It's not running on biofuels or renewable electricity because those options aren't realistic for us.

So we offset the small amount of emissions we produce. Without offsets, we wouldn't have an option available to us.

However, offsetting as a first (or only) step is misplaced and misguided. But, unfortunately for many people, and esp. businesses, it's attractive.

But what that means is simply "paying more" to do the same thing. It misses an opportunity - a potentially lucrative one for business. Gil Friend talks about this a lot - businesses look at the cost of making their processes environmentally friendly, rather than rethinking them.

By rethinking businesses can reduce waste, inputs, costs and potentially improve their product and position in the market.

If offsets are the first choice, then we don't see that kind of innovation.

It should be said, too, that some offset providers, like Climate Friendly (who provides CDM audited offsets), are starting to promote to it's customers that same "Reduce, Renew, Offset" idea - which is great to see, and a responsible step I think.

IMHO, offsets are a useful option, and shouldn't be disregarded. But they are far from a silver bullet.

Grant said...

I forgot to mention - I've very dubious about tree-based offsets. Not only is the carbon likely to re-enter the atmosphere through natural processes eventually, the practice also doesn't change our patterns.

Offsets that are tied to renewable energy projects are my fave, because they are supporting systemic change.

David Jeffery said...

Thanks for your comments all - some excellent points there.

Ru said...

People who are doing a very carbon intensive activity (flying)pay me to plant a tree for them. We are completely honest about the timescales for reabsorption and we tag every single tree for verification purposes.
Trees can provide a very secure, long term carbon sink. There are trees alive in the U.S. today that were absorbing atmospheric carbon when they were building the pyramids. If the trees are harvested for timber and then kept dry they can retain the absorbed carbon for a thousand years or more. We would be really stupid not to take advantage of the immense absorptive capabilities of trees at a time when we have dangerously high concentrations of CO2 in our atmosphere. One more thing. The trees we put in today will be doing their best sequestration work in 60 or 80 years when our fight for mitigation will be far more difficult than it is today.

I put in 50 trees this morning, they'll each fix at least 1/2 a tonne of CO2 over their lives Thats 25 tonnes in 80 years time.
This is a small but substantive contribution to the fight. Its easy to criticise tree offsets but what did you do this morning?