Dr. Hannah Daly:

I echo much of what Professor Ó Gallachóir has said about the need for continued support and capacity. While there were a number of data gaps, there is a real bottleneck with regard to our capacity to feed into this process. Through this process, we are training PhD students in both modelling and communications. Processes like this can be improved by making national datasets as freely available and open as possible so that we can build from the data and modelling of other groups and replicate and update that work as things change. Adopting a principle of making data as open as possible would really assist with this process.

Modelling itself is just one part of this process. Other parts include defining the question, creating the model, producing the results and engaging in this iterative engagement between the policy system, stakeholders and scientists. Ideally, this process should be as iterative and strong as possible so that we can gain insights. We can see what kind of scenario is feasible within the world of models but we cannot make judgments about the scale of change that is feasible politically or societally. That is really important.

I agree with Professor Ó Gallachóir that the representation of society and demands should be improved and the distributional impacts of these energy scenarios considered because our models do not assess who pays, what type of finance is used and what the impacts of that are. It is also very important to look at the co-benefits such as the reduction in air pollution that results from climate mitigation measures and the potential to develop good-quality jobs. Correspondingly, it is also important to look at where jobs will be lost. Integrating the wider sustainable development goals into these models will be a priority in future.

Another big priority for the energy system model is equipping it to look at net zero to beyond 2030. We have shifted the model greatly to focus on the next decade and on how quickly the system can change. We want to move the focus beyond 2030. For example, we want to examine how ambitious we can be for the third carbon budget period. There are to be reductions in emissions of more than 8% annually in the second carbon budget period. Can that be sustained or even grown? Can we bring forward the date at which we will achieve net zero as the urgency of climate mitigation becomes more apparent in the coming decades?

I will say a final word on the integration of models. As we move towards 2050 and net zero, the interactions between the food system, land system and energy system will become much more apparent. There will be synergies. Dr. Styles alluded to some of these, for example, using wood for bioenergy as well as for construction, where it will replace cement. There will be lots of different systemic interactions but that will create competition for agriculture. There will be trade-offs. For example, re-wetting land will reduce the capacity to afforest it and to produce food. I would not necessarily like to have one fully integrated model but representing these interlinkages between energy, food and land in the context of carbon neutrality will be the main priority.