Does carbon offsetting work?

What is carbon offsetting?

The idea behind carbon offsetting is that the carbon emissions generated through an activity (like flying) can be calculated, and then the equivalent amount “paid off” via a scheme which removes carbon from the atmosphere (such as tree planting). To work, the "carbon removal" scheme or project must be in addition to existing schemes. And as we’ll see, that isn’t as simple as it sounds.

The race to net zero emissions

Right now, companies, councils and countries are falling over themselves to declare that they are going to go “net zero” (removing as many emissions as we produce), with dates ranging from 2030 to 2050. Net zero doesn’t mean they are going to reduce greenhouse gas emissions to actual zero, it means they are going to reduce their emissions a lot (or just a bit) and fund an offsetting project to deal with their remaining emissions. Bingo, net zero. 

Does carbon offsetting work (in practice)?

One the one hand that’s a pretty easy question to answer. A study for the European Commission [PDF] into United Nations-sanctioned offset projects found that three-quarters of projects were unlikely to have resulted in additional emissions reductions (meaning they would have probably gone ahead anyway) and only 2% had a high likelihood of being classed as "additional". So, in most cases it seems clear that carbon offsetting doesn’t work in practice. But on the other hand, that doesn’t mean it never works, and it clearly depends on which projects are being funded.

Are there examples of good offset projects?

That’s not as straightforward a question as it may seem, either:

Firstly, as mentioned before, the offset project must be in addition to what was going to happen anyway. That’s more difficult to identify than you’d think, because you need to have a crystal ball to identify what will happen without the offset cash. For example, the study for the European Commission (see above) basically said most energy-related projects are likely to happen anyway because there is already a strong demand for energy and a market that will pay.  And under the international Paris Climate Change Agreement, governments have already pledged to reduce emissions and therefore will need to ensure many of the typical offset projects go ahead anyway, so they won’t be in addition.

Secondly, the offset project must permanently lock away the emissions. Tree planting is a very popular offset scheme, largely because it’s a lot cheaper than other schemes. But sadly, trees can burn down (just look at the horrendous fires in Australia), be killed by pests (a university study showed tree deaths by pests in the USA are equal to the emissions of 5 million cars every year), or chopped down to make way for farming, roads, and so on. Don’t get us wrong, we’re all for tree planting at Friends of the Earth. But to be a viable offset project, the carbon must be locked away for thousands of years and tree planting or peatland restoration can’t guarantee this.

Thirdly, the offset project mustn’t lead to emissions just shifting elsewhere. Bizarre as it seems, some offset projects say “give us your money and we’ll stop some forest being chopped down”. But as a report funded by the German government [PDF] pointed out, it is very difficult to identify if a forest area is at risk of being chopped down, even in an area of high historic deforestation. Protecting one specific area of forest may also result in a different area being chopped down because the driver of deforestation hasn’t changed (for instance, the insatiable demand for meat across the world).

Fourthly, the offset project must draw down more carbon than is being emitted. The European Commission report (see above) said that this isn’t always the case. For example, it said that most schemes that help households in developing countries switch from inefficient cooking stoves to efficient ones exaggerate the savings in emissions. Also, 1 tonne of carbon from a plane causes more harm than 1 tonne of carbon from other sources because burning fuel at altitude causes other changes that increase the warming effect.

There will be some offset projects that are genuinely “additional”, will permanently lock away carbon emissions, don’t just lead to more emissions elsewhere and don’t draw down less emissions than being emitted. They will be few and far between, but they will exist. However, that’s not the end of the story.

Does carbon offsetting delay emissions reduction?

The prospect of being able to offset emissions, for example through tree planting or future technologies that could suck carbon out of the atmosphere, could encourage politicians, companies or even individuals to dial back on actions which will reduce emissions today (for example, by deciding not to fund energy efficiency schemes).

Academics at Lancaster University have been studying this issue, and they concluded that even the very promise of these kinds of future offset schemes can deter or delay action to reduce our emissions. In other words, governments, businesses and individuals are going to avoid taking challenging decisions because current or future offset projects provide an easy way out (a "get out of jail free" card). While this may not seem a big deal, it’s the large scale equivalent to you or I nudging the heating thermostat up a degree rather than grabbing a jumper. Clearly it makes a big difference if a government decides to allow aviation expansion or spends billions on new roads, because it claims the resultant emissions can be offset in the future.

The academics suggest that in the worst case scenario, the promise of the schemes alone could lead to an additional catastrophic 1.4 degrees of warming. They say we need to reduce emissions as much as possible and invest in projects to remove carbon dioxide from the atmosphere, not choose one or the other. They didn’t quite say “ban offsetting”, but they came close.

What can I do to cut my emissions?

There are plenty of ways you can reduce your individual carbon footprint, such as avoiding air travel, reducing meat and dairy intake or fitting your home with eco-heating. You could try to find the perfect offset project (but as we’ve described above, most of them are highly dubious to say the least). If you’ve adopted any, or all, of these measures, you're a star.

However, not everyone is in a position to make those changes. You may not be able to afford to, or perhaps (like many people) you don't own your own home. 

And as great as individual action is, we need systemic change if we're to reduce emissions sufficiently to avoid complete climate breakdown. So the best thing you can do to further reduce carbon emissions? Join a local action group and lobby for change in your community. 

Should countries offset?

Some countries are trying to offset their emissions to avoid having to take action within their own country. The theory is that in a world where some countries need to get to net zero and others don’t, the country that does need to get to net zero can pay another country to go further (eg cut its emissions by 90% rather than 80%). But in a world where every country needs to get to net zero, that theory falls apart. 

And in any case, the countries that are most likely to want to use this approach are the big wealthy ones, and in practice they can use their economic and political power to bully smaller and poorer countries to offset more than their fair share of emissions. In practice, this nation-to-nation offsetting isn’t fair and Friends of the Earth doesn’t support it.

What is biodiversity offsetting?

Biodiversity offsetting is looking like the next big ruse. If given the go-ahead, developers could rip up a wildlife-rich area to build homes and offset the damage by putting money into a wildlife restoration project – perhaps many if not hundreds of miles away. Apart from the obvious problem that every habitat is unique, and that the local community may have just lost a wildlife area on their doorstep, international experience demonstrates biodiversity offsetting just doesn’t work. My colleague Paul de Zylva has looked in detail into these proposals and produced a damning critique.

So, does carbon offsetting work?

In most cases, sadly it does not. It’s a con.

If a business or someone you know tells you they are going net zero, ask them just how far they are going in cutting their emissions. If someone tries to sell you an offset project, ask them if they will guarantee the carbon will be locked up for thousands of years and that the project has zero chance of being funded in any other way.

The reality is that we – government, businesses and individuals – need to cut our emissions by as much as we can, as fast as we can. We also need to invest in projects that will remove carbon emissions from the atmosphere. It’s not either/ or, it’s both. The same is true of nature. We need to protect what nature we have left, and we need to restore habitats, not one or the other.