We have heard about the end of fossil fuels for several dozen years. Is the moment really at hand?

When I graduated from university in the 70s, it was said that global oil resources shall last for 20-30 years. Since then, over 40 years have passed and combustion engines and oil companies are doing very well. Currently, it is said that the moment at which oil runs out will be in around 50 years. But these are only calculations. Let us leave the calculations of the date of world oil resources exhaustion to others. We shall stick to the statement that such types of fuel shall eventually be exhausted. That is why we should look for other solutions. Surely, I think that using oil-derived fuels for other purposes than transport is a waste. Energy for heating or for industry should be produced from renewable resources (wind, water) or in nuclear power plants. Today, in the light of the catastrophe in Japan, nuclear energy loses popularity, but it is the most effective way of producing electric energy and it is very safe provided that appropriate procedures are adhered to.

Therefore, the near future won’t bring much change in public transport vehicles?

In fact, it is quite the opposite. The next years will bring huge change. The question is: which direction should it take? Over the last few years, the notion of sustainable development has become quite popular. It can be interpreted in many ways. My interpretation is that we should develop existing transport means in a balanced and optimal way. In practice, it means buses as well as metros, railways, trams and trolleybuses alike. There is a lot of potential for further development in all of these fields. Let’s just take a look at what we were able to do with combustion engines in the last decades. For example, from the beginning of the 50s until now, the average emission of nitric oxides by combustion engines was reduced 180-fold! Furthermore, since the introduction of emission standards at the beginning of the 90s, the emission of toxic components was reduced by as much as 99%. It is even easier to image the progress in this field if we try to remember how it used to be like to drive behind a bus or a truck. A black cloud of smoke impaired our vision and our ability to breathe. Today, the things that come out of the exhaust system are not seen by the naked eye or smelled by the nose. Of course, it is getting harder to achieve further development in this field, but it is possible. This regards the structure of the engine, as well as increasing its effectiveness and limiting its need for fuel. Another element of transport that can be significantly improved is the organization of street traffic in cities. Increasingly, we see dedicated bus lanes or Bus Rapid Transit (BRT) systems, adapted for operation of special vehicles. We also have ideas like city highways or progressive traffic light sequencing. Due to smooth traffic flows alone it is possible to reduce fuel consumption by 30%. This enables huge savings if we look at a global scale.

Until now, we have been talking about vehicles with combustion engines. What about electric vehicles?

Combustion-engined vehicles still dominate in our world and shall dominate for a long time still. Undoubtedly though, electric vehicles are another segment that should be developed to achieve sustainable development. We have trams and trolleybuses, tried and proven for almost 100 years. However, there is more and more talk about electric vehicles. In autumn of last year, Solaris presented the first electric bus in Poland. The benefits from using an electric drive are obvious: long service life of traction engines and their high efficiency, maximum torque from the start and the possibility of energy recuperation during braking. Furthermore, lack of emission at the point of use and less noise. On the other hand, the biggest flaw of electric vehicles is their power supply. We have overheard traction supplies for railways, trams or trolleybuses. This problem is key with cars and buses. Thus, we reach the biggest challenge that constructors of such vehicles face: energy storage. Currently, we have two possibilities: supercapacitors, which are charged very quickly and supply energy just as fast, and batteries, which can store much more energy, but need a lot of time to load. Finally, to hold a sufficient amount of energy, batteries have a specific weight. To compare, for current batteries to store the same amount of energy as a 40 kg tank of traditional fuel, they would have to weigh 500 kg. Besides, batteries are much more susceptible to temperature. Below zero degrees, their service life decreases dramatically. If we assume that a public transport bus should be able to drive around 350 km on a single charge, then such batteries would have to weigh several tons. This means that such a vehicle could take a significantly lower number of passengers. Of course, we can try to balance that weight by reducing the vehicle weight in other elements. Undoubtedly, a very important issue inhibiting the spread of electric vehicles is the price of the technology and its limited availability. Obviously, I don’t want to say that electric vehicles do not have a future. I just want to show how many problems still need to be solved. But returning to the example of Solaris, about a year ago I saw a presentation of Krzysztof Olszewski, who presented conceptual ideas about an electric bus. He then said, "Let us dream!". This is wonderful and the problem should be approached in such a manner. We have to have dreams. Without them, there is no progress. Today, Solaris is presenting a prototype of an electric bus. What will happen in a few months or years? Who knows? Maybe no one will question the choice of such a solution anymore. At the moment, the series hybrid is an optimal vehicle in these terms. Solaris also offers such a bus. This vehicle can drive in electric mode, but it also has a small combustion engine at its disposal to support the electric engine in critical moments. All this is, of course, a subjective evaluation of the current situation. In a couple of years, the development of electric vehicles might show that I was wrong.

What if you weren’t afraid of dreaming and were asked to say what your image of perfect public transport in dozen years might be?

If we assume that my dreams are not bound by economic constraints, then a perfect city should have a metro, ideally driverless, but it should also have room for trams and buses, electric and hybrid alike. They would operate on separate lanes, consuming minimum quantities of traditional fuel. Charging stations for electric vehicles would be as common as petrol stations are today. I hope that this is not only a dream, but a vision of the future that is possible to realise. There is the question: what would Solaris work on then? I don’t know. But surely, at the Institute for Combustion Engines and Transport, we shall gladly take part in the big challenge of this research.

Professor Merkisz, thank you for your time.