Testing of battery trolleybus in Pilsen
19 November 2020
A test line served by battery trolleybuses (line 19) was operated in Pilsen between the 2 December 2019 and 26 June 2020 on the route between the Central cemetery in the Eastern part of the city and village-liked quarters Křimice and Malesice in its Western part, normally operated by 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 one kilometre longer. 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, the 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 agreed with PMDP on adjustments to the settings of the vehicles. Beside the vehicles manufactured by Škoda, PMDP also tested a battery trolleybus of Ekova, another Czech manufacturer based in Ostrava, which provided a lot of interesting comparisons to values and conditions for both drivers and passengers, already used to Škoda standards.
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 of the trolleybuses by forced ventilation. As the outside temperatures did not exceed 26 ° C even in June, a special temperature test was performed in August on line 13. This showed that although the temperature of the batteries under stress rises during the day, the cooling of the batteries is sufficient. The route to Malesice and Křimice also has the advantage that it is in flat terrain and the batteries are stressed evenly.
The testing phase on line 19 ended on the 26h June 2020. A permanent new trolleybus line on this route, consisting of the merged lines 11 (trolleybus line) and 35 (bus line) that are currently operating between the Central cemetery and city centre, resp. city centre and Křimice/Malesice, should be launched in autumn 2021.