This workshop set out to address four key questions, a) to d), identified prior to the event. Experts were invited to tackle these questions through means of a preworkshop briefing paper. These papers were circulated to participants in advance of the workshop. The authors presented a brief summary of their paper during the workshop and participants were invited to discuss the issues raised by the paper and any other related issues. The briefing papers are available in the Appendices of the full report, which can be downloaded from the UKERC website.