Interview with Gunnar Luderer
To mark Earth Day on April 22, we have compiled assessments on climate change by leading scientists in a dossier. Gunnar Luderer is Deputy Chair of the Department for Sustainable Transformation Pathways at the Potsdam Institute for Climate Impact Research (PIK). In an interview, he explains how individuals can act to protect the climate – and what politicians should do. In addition to his duties at PIK, Luderer is Professor for Global Energy Systems Analysis at the Technical University of Berlin.
Especially in the industrialized countries, CO₂ emissions per capita are far too high. In Germany, for example, they are 8,600 kilograms per year. How does that add up?
Especially in the industrialized countries, CO₂ emissions per capita are far too high. In Germany, for example, they are 8,600 kilograms per year. How does that add up? About one third is produced when burning coal, oil and gas to generate electricity. The heating of buildings contributes another sixth of the emissions. Roughly a quarter comes from the transport sector, with road transport accounting for the largest share. Another quarter is attributed to industry. Together with the emissions from agriculture, this results in per capita emissions, which is a calculated figure. Each and every one of us contributes to this, but important commercial enterprises such as Volkswagen naturally do so to a particular degree – both through their own energy consumption and through their products, namely cars with combustion engines. That is why it is so important that Volkswagen, too, assumes responsibility and develops new solutions for clean mobility. At the moment, people and companies have completely different and much more pressing concerns, and I too have them. But unfortunately, the climate problem does not go away.
What values are compatible with effective climate protection?
If we want to stabilize our climate and limit warming to less than two degrees Celsius, so that we don’t have more and more extreme weather, as well as rising sea-levels and so on, then we have to achieve net zero emissions by the middle of the century. Zero, in fact. There may still be the release of methane from agriculture, which is also a greenhouse gas, or a few industrial process emissions that are difficult to avoid, but these would then have to be offset by so-called negative emissions, in other words by removing greenhouse gases from the atmosphere again. Trees do that, for example, and the injection of CO₂ underground is also an approach, but the technologies are expensive and land for reforestation is limited. That is why we need to start reducing emissions as soon as possible. The later we do this, the steeper the emission curve must then go down – and the more expensive it will be.
How much influence can a person have based on personal actions?
Of course, individuals can try to change their consumption habits – but all this cannot be a substitute for the appropriate framework set by politicians. The decision-makers who are legitimized to do so, as a result of elections, must set guidelines, such as an effectively high and comprehensive price on CO₂. This price applies to all products, always in accordance with their emissions intensity. This then changes the incentives for companies and consumers alike. And it can give a boost to innovation in the field of zero-emission technologies. Our research shows very clearly that such a price signal is by far the most effective instrument for climate protection. In some areas, however, it needs to be supplemented by regulation and funding programs – for example, to advance the charging infrastructure for electromobility or to help low-income households make the switch.
“A more sustainable diet with less meat and dairy products, but more vegetables and fruit – that is not only good for the planet, but also healthier for each individual”
What exactly can each individual do to reduce their CO₂ footprint?
Of course, one can fly away on holiday less often and rather spend more holiday time in Germany. Or not eat so much cheap meat, that would also be healthier. You can draw electricity from renewable energies for your home. But once again: the political framework is crucial. What the individual can do: is to make your preferences clear to policymakers. But you can also simply talk to your neighbors about the issues.
What possibilities are there for mobility?
Mobility is a basic human need and one of the great achievements of modern societies – especially in the current crisis, this is once again very clearly demonstrated to us. But we need a comprehensive turnaround in transport – not only to achieve climate targets, but also to tackle road congestion, noise pollution and air pollution. To do this, we need to move away from the internal combustion engine – the future will be electric in the passenger car sector. In the future, mobility service providers such as MOIA will be able to close the gap between walking and cycling and public transport in the cities with shared services. We are already observing that more and more city dwellers are foregoing their own car. In rural areas, on the other hand, it is difficult to get by without a car. Electric mobility will play a major role here.
Suppose I want to start right away – what are your most important tips?
Firstly: electricity consumption. The easiest way to protect the climate in your own household is to switch to green electricity. This costs only slightly more than conventional electricity, and with the average consumption of a four-person household, reduces the carbon footprint by almost three tons of CO₂ per year. Second: nutrition. A more sustainable diet with less meat and dairy products, but more vegetables and fruit – that is not only good for the planet, but also healthier for each individual. Another thing: far too much food ends up in the trash. Only buy and cook as much as you actually eat. Third: Mobility. There are many starting points here. What distances can I cover by bicycle or on foot? Is a smaller car enough for me or can I even switch to an electric car? When travelling by air to far flung destinations, it is better to stay longer and travel less frequently.
The corona pandemic is causing economic output and thus CO₂ emissions to shrink. How do you assess this impact?
The corona pandemic is terrible and does not help us make any progress in climate protection. On the one hand, the fall in emissions is temporary and the resulting economic damage is something we would all like to avoid. On the other hand, the corona crisis is causing so much human suffering – it would be damned cynical to rejoice in the emission reductions and ignore this suffering. We can all only hope that this crisis will be overcome as soon as possible so that businesses and people can get back to normal. Then, together and with fresh vigor, we can tackle the transformation towards sustainable prosperity. Now that would be nice.