Approved work: Carbon offsetting and carbon payback
This POSTnote will summarise the challenges that have emerged around setting standards for international offsetting and what monitoring is needed to ensure effective mitigation.

This POSTnote reviews the main types of low-carbon aviation fuels and their potential for use, as well as associated challenges and opportunities. It supplements POSTnote 615: Climate Change and Aviation.
Low-carbon aviation fuels (303 KB , PDF)
Key points
Low-carbon aviation fuels can replace conventional aircraft fuel (jet fuel) to reduce greenhouse gas emissions from flights. Estimates suggest that they could mitigate between 5% and 30% of carbon dioxide (CO2) emissions from UK aviation by 2050. These fuels do not require major changes to aircraft or airports and could in theory be implemented immediately. They can be used in long-haul flights, where other options for mitigating emissions are limited. Several airlines have invested in these fuels, seven airports supply them and six production methods are currently certified, with more under review.
However, the uptake of low-carbon aviation fuels has been low. In 2017, 0.002% of total fuel consumption by aircraft was from low-carbon fuels. The main barriers are the high production costs and high levels of required upfront capital investment. Aviation fuels need to be very energy dense, and safety requirements are strict, mean that timelines for developing and certifying fuels are long. Aviation also competes for low-carbon fuel technologies and for the use of biomass with the road transport sector electricity production sector.
POSTnote 615: Climate Change and Aviation is available online.
Acknowledgements
POSTnotes are based on literature reviews and interviews with a range of stakeholders, and are externally peer reviewed. POST would like to thank interviewees and peer reviewers for kindly giving up their time during the preparation of this briefing, including:
(*denotes contributors who externally reviewed the POSTnote)
Low-carbon aviation fuels (303 KB , PDF)
This POSTnote will summarise the challenges that have emerged around setting standards for international offsetting and what monitoring is needed to ensure effective mitigation.
This POSTnote will summarise the evidence base for restoration measures for different freshwater habitat types (complimenting the recent POSTnote and POSTbrief on habitat restoration) and the outcomes for biodiversity and ecosystem service benefits such as natural flood management and water quality.
This POSTnote will summarise the challenges and opportunities for the different approaches for reducing the use of synthetic fertilisers.