Professor Hans Joachim Schellnhuber, a climate researcher, on the development of global energy systems, their effects on climate change, and why an energy transformation is necessary not only in Germany.

The 80% figure sounds very abstract when you hear it. However, the target is more important than ever if we want to maintain the so-called two-degree line, which means limiting the global temperature increase to two degrees Celsius above the pre-industrial level between now and 2100. That’s because if we exceed the two degree limit, we very likely won’t be able to manage the resulting climate-change consequences in any reasonable way. Let me give you an example: My institute recently wrote a climate report for the World Bank in which we described what would happen in a world four degrees warmer than ours. The situation would be disastrous — especially in the developing countries. For example, they would frequently experience the sort of heat wave that would normally only occur once every million years in a stable tropical climate — not every seond year, as would be the case in this scenario. The impact of this warming would be so great that we can’t imagine how the affected regions could possibly adapt to the new climate. That’s why I always stress the fact that achieving an 80% reduction in greenhouse gas emissions by 2050 as compared to 1990 is of vital importance.

Some say the temperature increase between now and 2100 will be even more severe than what’s been predicted, while others claim it won’t be as bad. What’s your opinion, and what can we expect to happen if the world can not agree on common climate goals?

Based on what’s in the media, there appear to be two groups here. The first believes it’s now too late for us to achieve the two-degree objective. The second thinks global temperature can never rise by four degrees, regardless of how much coal, gas, or oil we burn over the next few decades. Given these views, one could simply calculate a mean and claim that the Earth’s temperature might rise by only three degrees, no matter what we do. This is nonsense, of course. It’s true that climate researchers examine various scenarios but the one closest to reality is based on the voluntary national commitments submitted to the Climate Change Secretariat after the UN Climate Change Conference in 2009 in Copenhagen. In line with the corresponding data, we can assume an increase in global temperature of approximately 3.5 degrees Celsius by the year 2100. Worse than that, because we hope the world will continue to exist after 2100, we can also assume that global warming will not simply stop after that date. In other words, 3.5 degrees of warming by 2100 also means five to six degrees of additional warming by the year 2300. This figure is the one we have to deal with if we assume that climate policy won’t change. So there’s still a great deal of work to be done.

Do you believe economic development can become more sustainable even without political regulation?

A lot is happening today even without government intervention. The key question is how innovations can impact developments, whereby cost considerations play a major role here. For example, if a barrel of oil only cost ten dollars today, as was the case for quite some time, no one would be talking about energy efficiency. Indeed, if it weren’t for the supposed crackpots who claimed that wind power might someday significantly contribute to a future energy mix, we probably would have relied solely on cheap nuclear energy as a response to the skyrocketing oil prices we experienced in the 1970s. We need such people with visionary ideas. After all, those who were derided as oddballs in the 70s actually paved the way for what is today a global industry. So, as you can see, society is very complex on all levels, and regardless of whether you’re a wind farmer or a politician, you can do something to promote innovation — or inhibit it.

Other countries are also transforming their energy systems — for example, the U.S., which is moving toward gas, and China, which is focusing on coal, renewables, and nuclear power. How do you view these developments against the backdrop of climate change?

Ernest Moniz, the nominee to become the new Secretary of Energy in the U.S., is a man I know very well. Mr. Moniz doesn’t question the reality of climate change, and he knows the U.S. must employ every available means to make the transition to a sustainable energy system. By this I mean the use of gas, carbon capture and storage (CCS), nuclear power, biomass, and renewables. In this sense, America is basically utilizing an approach similar to that of the Chinese, who are also pursuing different options simultaneously and hoping that some of them will prove effective. The thing is that all of these countries must at some point draw a line and decide on the best alternative; otherwise they won’t be able to finance such an energy policy over the long term. That’s why I believe both China and the U.S. will decide relatively soon which type of energy mix is most feasible for their requirements. I also believe energy efficiency will ultimately be given tremendous importance and that in the end, renewable sources will prove to be a cost-effective alternative to conventional power plants.

What do we have to pay attention to if the transition to a sustainable energy system is to be successful? How important is the efficient use of energy, and what can be achieved with it?

If you’re asking me how we can reach the two degree target on the global, European, and national level, then I’ll tell you that energy efficiency will play a very important role here. That’s because energy efficiency will have to provide for one third of the reduction in emissions required to achieve this climate goal. Energy efficiency is good for the climate. It conserves resources that can be used more effectively elsewhere, and it also reduces costs. Despite these benefits, we have an interesting situation in Europe at the moment. Back in 2007, the European Union set itself the so-called 20-20-20 target, which means a 20% share of renewables in the primary energy mix, 20% lower greenhouse gas emissions, and a 20% improvement in energy efficiency, all as compared to 1990 levels. The first two targets are binding; the third, for energy efficiency, is not. Moreover, whereas the first two targets can be achieved easily by 2020, we’re now falling behind significantly in terms of efficiency. Energy efficiency is important, but achieving it requires everyone to cooperate.

Can Germany’s energy transition serve as a model for other countries, which often have different needs to address?

In my opinion, many other countries have a much greater need for an energy transformation than Germany, which could manage to move into the industrial future with a relatively conventional energy mix. This is mainly because we’re very good at improving energy efficiency. However, the way I see it, a country like India will not be able to provide its population and industries with energy services over the long term unless it undergoes a dramatic transformation by moving toward the use of renewable energy sources, such as solar power. In other words, Germany’s energy transition is really an experiment that a highly industrialized and affluent country is pursuing — and for very good reasons, including the need to address climate change, the risks associated with nuclear power. In this sense, we’re a little like a test lab for many countries that need to implement an energy transition much more than we do. Populations are growing rapidly in certain countries — for example, in Africa — and a lot of these nations will be much more severely impacted by climate change than Germany. Many of these countries also don’t have much in the way of fossil resources. In other words, the least developed countries in the world today are precisely those that are situated in tropical and subtropical regions and lack fossil fuels such as oil and gas. Obviously, these nations have only one possibility, which is to expand the use of renewable energy sources and, most importantly, to begin using energy more efficiently.

What role are technology-focused companies like Siemens playing in climate protection today — and what can they do to improve climate protection in the future?

I believe companies like Siemens do important work in this field. The high-tech solutions they develop expand our options for limiting global warming. The innovations we need for climate protection could never be developed without talented engineers and system analysts. Siemens also publicly underscores the need for sustainable systems in the future. Still, I think more should be done in this respect. For example, such companies could significantly step up their public campaigns. They need to make clear that they’re on the side of people fighting for a sustainable future in a world worth living in, rather than on the side of those who would cling to their privileges at the expense of our children and grandchildren.

                                                                   The interview was conducted by Sebastian Webel