Energy Efficiency for Public Transport Infrastructure in Central Europe: EfficienCE shows first results
26 November 2020
One and a half year passed since a new Central European cooperation project has been kicked off. City authorities, public transport companies, universities and sustainable mobility consultants joined forces to explore and test energy efficiency measures and the role of renewable energies in public transport systems.
EfficienCE is a cooperation project funded by the Interreg CENTRAL EUROPE programme that aims at reducing the carbon footprint in the region. Most Central European cities have extensive public transport systems, which can form the basis of low-carbon mobility services. About two third of the commuters in the Central Europe program area are using public transport. Measures to increase the energy efficiency and share of renewables in public transport infrastructure can thus have a particularly high impact on reducing CO2.
Out of the four pilots included in the project, two were already implemented – despite the difficulties caused by COVID-19 pandemic.
Innovative photovoltaic films provide electricity to Vienna metro station
Vienna has been titled the world’s most liveable city for years. One of its aspects is the environmental sustainability. In line with the city’s green approach, Wiener Linien – the city’s public transport provider – constantly pays attention to energy efficiency. On 29 November Wiener Linien – together with Wien Energy – launched its unique pilot within the EfficienCE project: special photovoltaic films were installed on the flat roof at Ottakring underground station in Vienna. As early indications showed in May 2020, as much as 50% of the station’s power was generated from solar energy in peak hours. You can watch their short video here.
Photo: Wiener Linien
Battery buffer storage helps to manage peak charge of trolleybuses in Pilsen
A major feature of Pilsen’s public transportation is its low environmental impact. Two-thirds of all kilometres travelled are carried out by trams and trolleybuses, and buses mainly serve the outskirts of the city. The Pilsen City Transport Company (PMDP) has launched a series of tests of a battery buffer storage station at the final station of trolleybus line 16 at Sídliště Bory. This technology fits the dimensions of a small shipping container. The charging station has no power supply from electricity provider CEZ's external network - it is connected only to the trolleybus overhead wires from which its battery is continuously charged, and under load it is able to quickly supply a larger amount of energy back to the trolleybuses. The main function of the station is to strengthen places with insufficient power supply.
Another energy-efficient project of the Pilsen public transport is a test line served by battery trolleybuses (line 19) on a route which is only partly covered by catenary; the other part is normally operated by diesel buses. The main difficulty lies in the fact that the ride without catenary to Malesice and back measures 12 kilometres, and the variant including the quarter Křimice is even longer. The test line was operated between 2 December 2019 and 26 June 2020. PMDP intentionally begun with the operation of the test line in winter, so that the most extreme conditions could prove the reliability of eventual future permanent operation of battery trolleybuses on this route. However, winter season 2019/2020 was not characterized by low temperatures and whole day frost. Nevertheless, each vehicle drove 230 km a day in 15 hours, of which 57% on batteries, so the vehicles were tested thoroughly. The test regime was also welcomed by the vehicle manufacturer: they continuously consulted on adjustments to the settings of the vehicles.
Operation on line 19 has confirmed that heating on frosty days doubles consumption. In this case, it is important that the trolleybuses leave the wires fully charged. After returning from the longest route to Křimice, there is still a sufficient reserve for normal operation, even a trolleybus occupied by 70 passengers successfully passed the test of on the 18 December. However, it would be optimal to ensure at least short-term charging on this route. The fuel consumption of the vehicles is also increased by air conditioning, but only fractionally compared to heating. The decrease in capacity due to the batteries’ age after several years of intensive operation remains unknown. Another aspect monitored is the cooling of batteries by forced ventilation. Based on the positive results, a permanent new trolleybus line on this route should be launched in autumn 2021.
Maribor examines its cable car system, preparing to charge electric buses
Maribor installed a smart meter device which is used to measure the load power. It is configured to monitor the total consumption of the Pohorje cableway. In the future, an electric bus fast charger is planned to be installed here. That time, there will be two measuring devices: one for the charging station and the other for all other consumers together. However, the sum of their powers represents the total load on the transformer. The local recording of consumption data is transmitted to a server of the University of Maribor. In view of the variable consumption of the substation in relation to the seasons and regular annual sports events, the University of Maribor will carry out comparable measurements, i.e. at the same duration and at the same time of the year.
From 15th to 18th of October the Downhill World Cup was organized in Maribor. At the international competition, which took place under the funicular, there were many power consumers connected to the substation they are measuring. In addition to the accompanying teams, there were also maintenance personnel, campers, and catering service providers. The event gave an insight into the load on the electrical system under stress conditions when organizing larger events.
Photo: University of Maribor
The graph below shows the active power from the substation below the funicular. Consumption increased during the competition, where the maximum active power was 284 kW on 15th October. These measurements will give Municipality of Maribor additional data in the field of power management planning for the fast-charging station.
Budapest goes electric
There are also several initiatives in Budapest as well to contribute to the sustainable development of the local public transport system. In September 2020 a fully electric urban bus “MAN Lion’s city 12e” was tested in the city. The test was carried out thanks to the cooperation between the manufacturer and BKK: this time Budapest’s public transport users could have the chance to get to know and test this brand new and innovative vehicle.
Budapest transport operator BKV’s latest energy-efficient investment, the solar-panel system installed on the premises of the Kelenföld Bus Division was inaugurated in September. The promotion of renewable energy and the provision of a cleaner and more liveable environment are two endeavours of BKV, which can also contribute to the realisation of the environmental and climate protection objectives in Budapest. On the roof of the two bus storage facilities BKV has installed a solar panel system whose total capacity is 200 kW, providing this capacity by a number of 648 solar panels, each of whose capacity is 310 W. The expected annual generated electricity is a total of 220.000 kWh, which can meet ca. 9% of the electricity demand of the facility, including 40% of the electricity demand of e-buses.
For more information please visit:
Marlene Damerau project manager
Phone: +49 221 660 5516