Shanghai has around 2000 formal bus lines (including city center, trolleybuses and suburban lines), served by more than 10 bus companies. In the past, Bashi, Dazhong, Guanzhong and Qiangsheng were the four largest; around 2009 they merged to become Bashi Group Companies, including Bashi No.1-6 Bus Passenger Service Companies, Bashi Tram, Bashi Xinxin and Chongming Company, Baoshan Company and Jinshan Company. Each Suburban district also renewed with one company serving each district. Around 2015, Bashi No.1 Passenger Service and Bashi Tram merged to be Bashi No.1 Company, Bashi No.2 Passenger Service became Bashi No.2 Company, Bashi No.3, No.4 Passenger Service merged to be Bashi No.3 Company, Bashi No.6 Passenger Service became Bashi No.4 Company, and Bashi No.5 Passenger Service and Baoshan Company became Bashi No.5 Company.Liveries of different bus companies differ. The most ordinary livery is often called "SH Livery", which was established in 2001. Bashi Group buses, Jinshan Bus Co. of Jinshan District, Minhang Bus Co. of Minhang District and other private bus companies use such kind of livery, while different in colors. Pudong Bus of Pudong New Area has its special livery established in 2009, which is blue and is often called "Haibao Livery". Songjiang Bus of Songjiang District has a livery of a combination of red and grey, which was established in 2007. Fengxian Bus of Fengxian District has a livery of green and white and another livery based on "SH Livery" but with the color of green and blue, which were established after Fengxian Bashi and Fengxian Bus (local owned).Qingpu Bus of Qingpu District started using new livery since the end of 2015, which contains the same color with Bashi "SH Livery" but has different patterns. Zongshen Dazhong of Qingpu District has a special livery of a combination of yellow and green on some of its bus routes.
Since 2006, Shanghai has been the leading Chinese system to implement electric and hybrid buses. During the 2010 Shanghai World Expo, the city piloted a program that includes 256 new energy buses with low to no emission. As of May 2015, the system has over 1,700 new energy buses, amounting to over 20% of the entire fleet.
During the mid-2000s, the city converted many traditional trolley routes to a standard diesel fleet because of route flexibility, speed, and eliminating the visual pollution of overhead wires. However, the obvious benefits of the trolley buses have brought back a renewed interest in keeping and developing the program. In 2013, Bashi Trolley Bus Company ordered 300 new trolleybuses to replace the aging fleet and grow the overall number of trolleys in Shanghai.
In February 2017, a number of ordinary bus lines running under the Yan'an Elevated Road was altered and transformed into Yan'an Road Medium-capacity System, or route 71路, a trolleybus bus rapid transit line running in the reserved lanes in the center of Yan'an Road. The line is served by a fleet of 40 Yutong ZK5180A articulated bus and 28 Yutong ZK5120C rigid dual-mode trolleybuses. Buses achieved an average operating speed of 17.6 km/h (10.9 mph) on the line. The line has an average weekday ridership of about 54,000 people, making itself the most used bus line in Shanghai. Line 71 doesn't share any overhead wires with other trolleybus routes.
On 28 July 2021, the Shanghai road transport department raised the issue of 'optimising' the traditional trolleybus network, which will result in the removal of all infrastructure on routes 6, 8, 13, 22, 25 and 28 to balance between historical value and space taken by wires. Trolleybuses on these routes will be replaced by electric buses.
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