Summary: 'Offsetting' is not a long-term sustainable solution to the problem of too much carbon use - if you work through the calculations, there is not enough land on the planet to plant enough trees, and not enough scope for replacing oil by yak dung and so on. The situation where 'offsetting' may help is where the maximum practical reduction in carbon use is being made - then 'offsetting' may alleviate some of the damage done by the remainder.
What is 'offsetting' ?The theory is that instead of reducing the amount of CO2 that you generate, you pay for someone else to reduce their CO2 emissions or absorb CO2 in some way.
Methods of 'offsetting'Principally tree planting, energy conservation, and funding research (e.g. into energy conservation and renewable energy).
Planting trees - pros and consThe theory is that by personally planting trees or contributing to a commercial organisation or charity that will do this, trees will be planted that will (as they grow) take up an amount of CO2 equal to what you generate.
One problem is that the trees will take decades to absorb the CO2 but you are generating it now - and we need to reduce CO2 emissions now. Another problem is that the trees will give back the CO2 into the atmosphere eventually when they die and decompose, and so as well as planting the trees, you have to ensure that the land where they are planted remains as woodland indefinitely - impossible to guarantee, especially as forests are now dying from drought or being destroyed in forest fires. Finally, and crucially, the amount of land needed makes this unsustainable in the long term.
Reducing CO2 emissions elsewhere - pros and consA commercial organisation or charity promises to set up a project where your money will reduce someone's CO2 emissions by replacing fossil fuel by a renewable source or some energy saving measure. The problems with this are that it is hard to be confident that this will actually happen.
Funding research - pros and consThe theory is that your money pays for research that will result in future reductions in CO2 emissions. The problem is finding a project that will achieve this - thousands of companies around the world are already spending large sums on developing technologies - the profit motive will almost certainly achieve this better than donations.
What others say
ConclusionsWe do not believe that any of the methods of 'offsetting' should form part of the plans to tackle climate change. The world is producing too much CO2, and we need to tackle this head-on by taking responsibility and reducing our emissions to a sustainable level. 'Offsetting' schemes probably do more harm than good by giving the impression that we can all carry on just as we are, with payment of just a few pounds/euros/dollars (and not asking awkward questions about whether they actually do any good).
First published: 2007
Last updated: 20 Nov 2018