Professor Barry McMullin:

I thank Deputy Whitmore for her excellent questions. We are already one year into this period, because 2021 is over. That is an immediate issue. Over the remaining nine years to 2030, I would prefer to see us achieving something more like 8% in reductions annually, rather than starting with a lower percentage and then ramping up to a higher rate in the last few years. I understand the logic of the argument made yesterday that some of the reductions would be easier to do if there is a longer lead-in time that allows for the building out of infrastructure and similar developments. That would be lovely. It would be great, if we had the time for it, and we do need to build out infrastructure as fast as we can.

In the meantime, however, we must reduce our emissions anyway. The only way to do that is to do less to cause emissions, and the only way to do that fairly is to ration the opportunity to do things.

Professor Ó Gallachóir rightly posed the challenge regarding how we could do this. My answer is focused mostly on the energy side, and on achieving our targets by placing an upstream limit on the entry of fossil fuels into the Irish economy. They can then be rationed out in a way that protects fairness and justice in the short term. It would mean that all of us, people, households, companies, enterprises and State agencies, would have to figure out how we can best pursue our normal goals. We would not tell people how to do it. We would leave it up to people themselves to have the freedom to figure out how to best pursue their goals, but in a scenario where there was a framework of stringent annual reductions in the available fossil fuel energy sources in the economy. That would mean doing less of certain kinds of activities. Returning to the earlier point made by Professor Anderson, it would mean wealthier people doing proportionately less of things that are proportionately more intensive in producing energy emissions.

If we build out our infrastructure, especially for renewable energy, as rapidly as we can in parallel with that approach by adopting a Marshall Plan-type scale of prioritisation of societal resources and devoting them to accomplishing our emissions reduction objective above all our other priorities, including building roads, for example, by focusing our resources relentlessly on the capital programme over the next ten to 15 years, then the restriction on people's use of energy could ease. If we want to be confident that we will meet stringent carbon budget targets, and to start early - and I agree with Professor Ó Gallachóir that it will be extremely difficult, while not agreeing that it is impossible - it will be a question of sharing the details of the predicament we are in with wider society, and doing so honestly, and then appealing for solidarity across our society. A system to fairly distribute the resultant burden across society would then have to be designed.

It would, essentially, be the same type of experience as we have been going through with Covid-19. The restrictions we had to put in place in the early stages of the pandemic were unthinkable previously. Yet we thought those thoughts and put them into action, because the alternatives were unthinkable. As the American journalist David Roberts said - and it is nearly ten years since he said it - we are trapped between what we think is impossible and what is unthinkable. The problem we are all collectively faced with is how to make the impossible possible, including, as I said, rationing fossil fuel energy in the short term and being honest and blunt about that requirement. I am blunt and honest about it. Achieving the early reductions in the time it will take to build out infrastructure means rationing. We have said, however, that we are going to stop the sale of new internal combustion vehicles from 2030. Why not make it 2028 or even 2025? We must absolutely think outside our previous, self-imposed restrictions on what is thinkable in this context.