Trolleybuses in Prague
Prague was the first city in Czechoslovakia to introduce modern-style trolleybuses. Only a few other trolleybus systems existed in the Czech lands previouslyin České Velenice (Gmünd) and České Budějoviceusing the same overhead system as the Electromote, the predecessor of all trolleybuses. Trolleybuses operated in Prague during two separate periods. The first trolleybus system was opened in 1936 and it lasted until 1972, when it was closed. After precisely 45 years, a new trolleybus system was opened in Prague in 2017. Existing network. At this particular time no trolleybus lines are in operation in Prague. However, 7  lines are in preparation and the first one should start its regular operation early in 2023, with testing operation expected to start at the end of 2022. Remaining should follow afterwards. Other lines are being discussed as well, but have not been approved yet. 1) This is an approximate number. Very short sections will not be wired near the Na Knížecí terminal. Also this line has 3 variants. For the shortest one most of the track is going to be covered with wires. For the longest one it would only be about 25%. However, with the addition of lines covering  area in between Nové Butovice and Velká Ohrada it will again rise the wired percentage way up even for the longest variant of this line. History. First system. The first system was opened on 28 September 1936 with a 3.5 km long line. After World War II, rapid expansion of the system occurred and trolleybuses appeared in the city center as well as in the suburban areas and big housing developments. The network reached its maximal length of 56.876 km in March 1959; however, even in 1959 the first and oldest trolleybus line was already closed. Most sections which were  in construction at that time were not finished and those in operation were slowly replaced with buses. Since 1960, no new trolleybuses were purchased, vehicles started becoming obsolete. Many streets were being reconstructed, there was not enough electricity available to run the network, and diesel fuel was inexpensive, which were among the reasons for the decision to begin replacing trolleybuses with buses, leading ultimately to the final closure of the Prague trolleybus system on 16 October 1972. Fleet. In 1936, the following Czech-made vehicles started operating on the Prague trolleybus system: In 1938 and 1939, two Škoda 2Tr trolleybuses  were delivered. A Tatra T400 began operating in Prague in 1948. In total, there were 136 new vehicles of this type, as well as eight secondhand such vehicles from Most, purchased and running in Prague. New vehicles were supplied in various series up to 1955, based on the previous experience with the vehicles as well as to utilize new technology. In 1958, a prototype of the Tatra T401 model was added to Prague's trolleybus fleet but it only lasted 3 years in operation. The performance and features of the Tatra T401 were tested during the first two years of  operation, after which it was decided that the Škoda Works, which produced smaller trolleybuses, would take over all trolleybus production in Czechoslovakia, and the Tatra company stopped producing any new trolleybuses. Finally, in 1960, the last 35 Škoda 8Tr trolleybuses were purchased for Prague. Tatra T400 and Škoda 8Tr vehicles were running in the city until the end of trolleybus operation in 1972. Attempts to re-open the system in the 1980s and early 1990s. Plans to restore trolleybus network in Prague started appearing in 1979. Soon after the political revolution of 1989, Prague's public transport company even delegated  money and people to look into the trolleybus network reinstatement. Also a prototype of a new trolleybus model, the Škoda 17Tr, was developed and produced in Prague. Since 1992, however, all plans to restore the network were dropped. Second system. After precisely 45 years, on 15 October 2017, a new trolleybus line was opened in Prague. So far, the system is equipped with overhead wires along less than 1 km of the route's length and requires trolleybuses with additional batteries, capable of operating away from the wires, along other parts of the route. The goal of this experimental project  is to prove the viability of trolleybuses in Prague as well as the ability to minimize the costs needed to build the infrastructure. Overhead wires have been installed along Prosecká Street, which features a steep gradient. This will prevent a fast battery drain for vehicles running upwards as well as quick-charging of their batteries for the rest of their journey outside of the wired portion of the route. In winter, the direct power supply will also allow for a tank of water to be heated up for interior heating. Prior to constructing a new trolleybus network Prague's public  transport company has already been trying out battery powered buses on various routes but as a result of these testing operations conducted in Prague starting from 2014 it was found out the statically charged vehicles tend to be very problematic on steep hills typical to Prague's landscape. The trolleybus network came as a direct response to address the major issues of the battery powered vehicles aiming to combine the best attributes of both worlds. The testing period should take about a year, and once finished it is hoped for the network to be extended and new articulated trolleybuses with  additional batteries purchased. The first vehicle to operate on the line was a Czech-made SOR TNB 12 "AcuMario"; however, it was a prototype, as it was the first such vehicle to be equipped with additional batteries. Opening ceremony. On the occasion of 45 years since the last trolleybus operated in Prague, as well as the opening of the new line Prague's public transport company, a public event was organized on 15 October 2017, on which the new SOR TNB 12 trolleybus was presented. It was accompanied by a new SOR ENS 12 electric bus and a historic Tatra  T400 vehicle from the Prague's public transport museum collection. It was possible for spectators to see all three vehicles in operation, as well as take a free ride. Regular operation. On 1 July Prague's Public Transport Company starts regular operation on a newly built line. The line will continue to have number 58 and will follow the same route as in the preceding testing stage, that is in between metro stations Palmovka and Letňany. Initially only 1 vehicle Škoda 30 Tr will be operated on the line running in 60 minutes interval. One year of operation anniversary. On  Sunday 14 October 2018 a second event since the opening of the new trolleybus system was organised. It took place in order to remember both the 46 anniversary of the original Prague's trolleybus system shutdown as well as to celebrate the one year anniversary of the current system. As opposed to the opening ceremony in 2017 the rides on a historic vehicle were not spontaneous but scheduled to took place 5 times exactly. Visitors who wanted to take a ride were also required to purchase tickets when entering the vehicle. Each ride cost 35 CZK per person and small  children were allowed free entrance if accompanied by an adult. The historic vehicle also differed as a smaller Škoda 8Tr was used, which is also why only about 40 people were allowed to take a ride each time. Every paying passenger was given a stamped paper ticket and a postcard with a picture of Škoda 8Tr when it was still in regular operation. Each ride started at the bottom of the hill, nearby Kundratka stop right at the beginning of the wired section, then took approximately 1 km up the hill and passengers were required to leave the vehicle at  the Kelerka stop at the end of the wired section. The trolleybus was then towed using a tractor all the way to Letňany roundabout (as it was supposedly the nearest safe place to turn the towed trolleybus) and back to the Kelerka stop to drive passengers back to the bottom section of the line at Kundratka stop. Škoda 8Tr was then towed again to allow for a new ride up. Every round took approximately 20 minutes in total, but only a small portion of it consisted of the actual ride as about 15 minutes were required for the up-the -hill off-wire manoeuvres. Visitors who didn't take the ride stood around the wired section to have a look and take photos and videos of the running attraction. Initial stage testing results. On April 11 the Prague's public transport company announced the news regarding the extension of the existing 1km long wired network. The plan war to replace all buses on line 140 connecting stations Palmovka and Miškovice by 2021. This has however been later delayed by one year to 2022. The final wired network won't cover the whole line but only a selected sections which  is why Prague's public transport company now inquires 15 articulated trolleybuses equipped with batteries. Based on the results from the system testing done in between October 2017 and April 2018 it was also requested the new buses to operate the route 140 should be able to charge their batteries faster, they should have a better acceleration running off wires on steep hills and should also be able to charge statically in depots. Electrification of the Palmovka - Čakovice section. On Wednesday 17 October 2018 "Pražský deník" newspaper published an article on the current state of the trolleybus network extension plans  mentioned in the "Initial stage testing results above". It was expected the wired sections will be built in 2020 - 2021 and the construction would take approximately 12 months in total. Approximately half of the bus line 140 was projected to be wired (8 Km). However construction permit was only available at the end of February 2021 so the work on this line (two individual sections) began on January 10 2022. Excluding some prep-work which has been merged with a reconstruction of Prosecká street in the first quarter of 2021 as well as bus stop reconstructions on Tupolevova street slightly  later that year. Overall, 3 substations are used to enable operation on this line. Two to power up the line itself and one for static vehicle charging in Klíčov depot. Interestingly, a substation in Letňany is an old abandoned substation originally used by trolleybuses. The other one has already been built with the initial testing and is being upgraded to allow full operation. So in the end the only new substation is built right for the operation of line 58 is the one in Klíčov depot. Decision on Nádraží Veleslavín - Airport section electrification. On Monday 16 September 2019 information about  3 new lines to be covered by trolleybuses with additional batteries has been revealed. This time on the other side of Prague (left bank of the Vltava river), utilizing a different depot in Řepy district. Work should start on electrifying bus line 119 connecting Prague with its main airport. Included should be charging station in Řepy depot (also usable for subsequent lines), in Veleslavín subway/train/bus interchange station and at the Prague's International Airport plus 4.8 km long section with overhead wires in between Veleslavín and intermediate bus stop Terminal 3. Other two bus lines 131 and 191  should follow once the work on the airport line is finished in 2023. Line 119 should be operated by high capacity double articulated trolleybuses with capacity higher than current regular articulated buses. In total 20 trolleybuses are supposed to be purchased for line 119, costing around 600 million CZK, while the wiring and depot preparation should only take half the sum. Decision on replacing bus lines 131, 137, 176 and 191 with respective trolleybus lines. On Monday, June 8 2020, Prague City Council has approved electrification of lines 131, 137, 176 and 191. The actual construction of the necessary infrastructure  should begin after lines 140 (Palmovka - Čakovice) and 119 (Nádraží Veleslavín - Airport) are finished, as was announced when line 119 was approved. This project is a logical step to follow after the conversion of line 119 considering line 191 can use part of that infrastructure. On top of that line 176 will also share a section of the catenary with line 191. Then all the additional lines will be built close to each other on the same bank of the Vltava river which also means a single depot will be able to serve them all and some power substations can  power up multiple nearby sections. In addition all 4 lines are passing through steep and/or long inclines which are well suited for a trolleybus operation. It is also interesting all lines except 191 were already operated by trolleybuses in the Prague's first trolleybus system epoch. Price to electrify the 4 new trolleybus lines is estimated to be in between 1 to 1.3 billion CZK in total. As with the preceding projects the lines are not supposed to be operated only partially under wires while for the rest vehicles will have to use batteries: Additional 130 million CZK should be  used to prepare Řepy depot for this trolleybus expansion. The construction should be completed by 2025. Future outlook. Even though the current trolleybus network is small, if testing is successful it could begin to grow in the next few years. Trolleybuses have strong support from within the public transport company, city major as well as public based on being both clean and efficient. The wired section of the current trolleybus system, while not covering the full length of the line, helps recharge batteries while the vehicle is in operation, which in turn reduces the need for high-capacity batteries and  their weight. Therefore, less energy is consumed on the ride and batteries can occupy much less space in the vehicle. This is also the reason for the trolleybus system's wired section being placed on the hilly, steep section, where battery consumption is enormous in comparison to operation on flat ground.