I also wasted some time going to a Cambridge Energy Forum discussion "Carbon Offsets – fix or fig-leaf?", but the debate centred on the technical issues. A common problem here!
So I added this post to the cam.misc topic (Carbon Offsets – fix or fig-leaf?)
" There is another issue with the voluntary offset market, which is about internationality. The concern for offsetting is to reduce personal carbon emissions. To be useful, this has to be part of a programme to make continuing reductions over the time until some target is reached. This should be 60% by 2050, in line with Kyoto as a minimum, or more realistically 90% or about 1.5 tonnes per person by 2030, as suggested by the likes of the Hadley Centre and WWF. Even if you believe in the role of offsetting in personal carbon reduction, the problem comes from the sustainability of the approach. If by 2025 you have reduced your personal emissions by 5 tonnes and offset the rest by purchasing 7 tonnes of offset, you are now totally dependant upon the CDM to maintain your lifestyle! The purpose of carbon trading and capped/validated offsetting is to prompt cost effective emission reductions, so we would expect projects to become scarcer and more expensive as time goes on. So in 2015 you now have to make the carbon savings that you have been putting off. On top of this there are the second order effects of having done so little. Eg.
* Easy jet claims there is still a demand for flying and a second runway is built at Stanstead.
* Tescos still see demand for out of town shopping and continue trash the local trade economy
* There is no demand for domestic renewable energy and the UK industry remains moribund.
So when you need to make changes, there is not a lot more you can do. So while ‘additionallity’ may mean that there is a first order saving, offsetting sends a message to the world that we don’t care about personal reduction and think that we can use the same imperial approach that got us here in the first place. If you want to discuss the moral issues, it would be more useful to read the chapter in heat by George Monbiot’s heat or look at ‘www.cheatneutral.com’
"