Busworld Europe 2019 offers a three-day conference, 21 to 23 October, in which Busworld Academy and UITP work together. Energy transition of bus transport, electric buses and how to implement those new fleets are a few of the main topics.
During the UITP Summit this summer in Stockholm there was a seminar 'Roll out and management of e-bus fleets', in which four transport authorities discussed the topic, two from Scandinavia, one from Italy and one from Luxembourg. The lectures are summarized in four articles here at Busworld Academy.
Since 2009, Luxembourg has been experimenting with alternative drives, Marcin Seredynski said. He is head of the Research and Innovation E-bus Competence Center in Luxembourg, a joint venture of Volvo Bus and Luxembourg Automobility Cluster. Seredynski started off with giving an answer to the question: why battery buses? "Simple, battery buses combine simplicity with efficient use of energy." He argues that battery buses have the lowest TCO concerning the environment if health and climate influences are included in the costs. “It's about much more than just emissions, otherwise you might as well buy a Euro 6d diesel bus, which is actually very clean. It is not about the bus alone, but about the complete public transport system. It will only become a 'green' system if more people start using it and leave their car.”
According to him, successful public transport systems are not those systems or cities where people are 'forced' to travel by public transport, but precisely those cities that have an efficient public transport system including good connections, stops and travel information. He refers to Luxembourg where, he says, the customer satisfaction score is one of the highest in the EU. Moreover, it is fair to state that the city of Luxembourg is often one major traffic congestion because in the past a failure was made in making the city accessible. Now the price is paid because of the many foreign commuters who enter the city every day. It is also the reason for making public transport 'free'.
In order to achieve a good system, Seredynski believes it is necessary to enter into good partnerships, particularly with electricity companies that will play an increasingly important role. Another party that plays an important role, according to him, is the driver. “The driver must be included in the entire transition story. In other words, you cannot do enough to educate the driver and make him familiar with this technology.”
Mild hybrid, hybrid and battery bus
He states that electrification of a bus fleet can consist of various techniques: mild hybrid, hybrid and battery. A mild hybrid is in fact a diesel bus with a small electrical adjustment to support the diesel engine, so it is definitely not an electric bus. On the other hand, a 'full hybrid' can drive up to 25 percent of the daily operating radius but an electrical infrastructure is needed, as does a battery bus. “Apart from the fact that it is probably technically impossible to get all buses electrically in the coming years, it is also economically pointless. We sometimes forget that Euro 6 diesel engines are pretty clean; mind you, dieselgate did not involve the public transport bus", says Seredynski. “With a battery bus, it is possible to get thirty percent of the energy required from recuperation. That is free energy. The same applies more or less to the full hybrids and to the mild hybrids in a much lesser extent due to the lower capacity. But very often these buses are equipped with stop-start systems. A further problem could be the climate system that requires the necessary energy and that is therefore closely connected to a battery bus."
He points out that it may be important to take the route schedule into account when using electric buses. “If the schedule is to tight, then the driver is inclined to drive fast and thereby waste a lot of energy. But on the other hand is congestion good for the energy level of an electric bus, because braking and driving recovers energy while little is used to pull up."
Off-peak and peak hours
“What we see in Luxembourg over the years is that battery technology is rapidly improving. In 2017 we received battery buses with a capacity of 100 kWh, while a year later buses with batteries of 200 kWh arrived. In addition, the capacity of the charging equipment is also increasing, while the price of all this is falling rapidly. In Luxembourg we now have more than 150 electric buses, including hybrids, and we have eight opportunity charging stations. This increased capacity offers the operator much greater flexibility because the radius is larger and less charging moments have to be taken into account," says Seredynski. He believes that increasing the battery capacity will not be the end of opportunity charging because it may still be economically viable to charge in the meantime because, for example, the electricity price is going to be influenced - off-peak and peak hours.
According to him, flexibility will ultimately be the magic word in which carriers will use the different systems side by side to achieve an economically meaningful operation.