Yutong ZK6128BEVG (E12)

The Yutong ZK6128BEVG (E12) is a fully electric single-deck city bus manufactured by Yutong in China. The Chinese manufacturer sells electric buses of different lengths and sizes for local and international markets.

10 units of the Yutong E12 bus were procured by the Land Transport Authority in 2018 as part of efforts to build a more environmentally friendly public bus fleet. A further 10 more Yutong E12DD double-deck electric buses would be acquired, for a total of 20 Yutong electric buses. In total, 60 electric buses were procured from three separate manufacturers at a total sum of S$50.64 million.

For Singapore road trials, buses are leased to Tower Transit (4 units), Go-Ahead (3 units) and SMRT Buses (3 units). Revenue service commenced on 3 April 2020, with buses initially deployed to Bus Services 15, 66, 944, 983 & 990 on a regular basis. Overnight chargers were installed at Bulim Bus Depot and Loyang Bus Depot, supplied by NARI.

Bus operators in China are primary customers of the Yutong E12, with units operating in multiple Chinese cities.  The bus has been successfully exported overseas, and as of 2020, units entered service in Santiago (Chile), Strasbourg and Marseille (France), Newport (UK), Reykjavik (Iceland), Helsinki (Finland), Roskilde (Denmark), Bergen (Norway), Sofia (Bulgaria), Nur-Sultan (Kazakhstan), and more.

Individual units have also been trialled in various parts of Australia, New Zealand and the United Kingdom.

Background

The Yutong E12 is marketed as a capable electric city bus featuring a suite of driver assistance features, passenger comfort and safety. The bus design incorporates large-capacity lithium iron phosphate batteries (375kWh) which allow the bus to travel roughly between 230 km and 300 km a single charge, under urban road conditions. The actual operating range is expected to be much lower in Singapore, where air-conditioning consumes a large portion of battery reserves.

Different range and power consumption figures have been quoted by different sources around the internet, depending on local route conditions under which the Yutong E12 was trialled. A range of 320 km has been quoted at 20°C without air-conditioning on. However, on Singapore road trials, the bus is confined to duties within 200 km, leaving an adequate margin of safety.

Yutong ReCtrl Electric Drive

Yutong's Electric Drive Technology (Click to expand)

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Introduction

The Yutong E12 is a fully electric city bus manufactured by the Chinese company Zhengzhou Yutong Bus Co., Ltd (郑州宇通客车股份有限公司), which manufactures road vehicles (primarily buses). The E12 is just one of Yutong’s electric bus products, alongside hybrid and regular diesel buses.

Photos of the Yutong E12 first appeared in Chinese commercial vehicle website 提加商用车网 in September 2019. The bus is seen navigating a test track located within Yutong’s assembly plant in Zhengzhou, China.

In comparison with Yutong E12 buses produced for other markets, the Yutong E12 buses in Singapore have the roof-mounted batteries split into two separate housing units; in front of and behind the air-conditioner, making for a split-type design. More information on the drivetrain can be found in the “Background” section above.

All Yutong E12 buses were registered between January and February 2020 as SG3090H – SG3099J, with SMRT Buses, Tower Transit Singapore and Go-Ahead Singapore receiving these buses. Revenue service commenced on Friday, 3 April 2020, with buses deployed on Service 15, 66, 944, 983 and 990.

Fleet

The 10 Yutong E12 buses are registered as SG3090H – SG3099J.

These buses, registered as YUTONG ELECTRIC ZK6128BEVG AUTO, are leased to the following operators:

• SG3090H, SG3091E, SG3092C (Registered on 2 Jan 2020) & SG3099J (Registered on 20 Feb 2020)
  Tower Transit Singapore
• SG3093A, SG3094Y, SG3095U (Registered on 3 Jan 2020)
  Go-Ahead Singapore
• SG3096S, SG3097P, SG3098L (Registered on 6 Jan 2020)
  SMRT Buses

Revenue service commenced on Friday, 3 April 2020 with the deployment of these buses on:

• Go-Ahead Bus Service 15
• SMRT Bus Services 944 & 983
• Tower Transit Bus Services 66 & 990

Formerly on Weekdays, the bus also operated on Go-Ahead Short Trip Service 15A. On Sundays & Public Holidays, a Yutong E12 bus was deployed on Tower Transit Short Trip Service 66A & 66B.

Redeployments

Tower Transit:

• 3 Apr 2020: Allocated to Bus Services 66 (2 units) & 990 (2 units)
• 28 Sep 2020: All 4 units redeployed to Service 189 & 189A. Scheduled interlining to Service 945 and 974A on Weekdays.
• 14 Oct 2020: 1 unit activated for EWL Bridging Service (between Buona Vista – Tuas Link) during MRT Service Disruption
• Jan 2021: Scheduled interlining for 945 & 974A removed
• 12 Apr 2021: Start of deployment on Service 77
• 6 May 2021: Start of deployment on Service 41
• 2 Aug 2021: Start of deployment on Service 944
• 25 Sep 2023: Buses deployed on 944 changed to operate on 992 with the renumbering of Service 944 on 24 Sep 2023.

Go-Ahead:

• 3 Apr 2020: Allocated to Bus Service 15 (3 units)
• 11 Oct 2020: All 3 units redeployed to Service 354. Scheduled interlining to Service 359 on Weekdays & Service 358 on Saturdays
• 5 Apr 2021: Start of deployment on Service 3
• 14 Apr 2021: All 3 units redeployed to Service 3
• 7 Nov 2023: 1 unit can be deployed on Service 384

SMRT Buses:

• 3 Apr 2020: Allocated to Bus Services 944 (2 units) & 983 (1 unit)
• Late Sep 2020: All 3 units allocated to Service 944
• 12 Apr 2021: Start of deployment on Service 184
• Late Apr 2021: All 3 units allocated to Service 184
• 25 Apr 2022: Buses redeployed to Services 172 & 61 with interlining to 991C

As for SMRT Buses, the Yutong E12 is the second model of Yutong bus in its fleet. It previously trialled a Yutong ZK6126 diesel bus (registered SMB135E) between 2009 and 2010.

Charging Infrastructure

For the overnight charging of the Yutong E12 buses, overnight chargers were installed at Bulim Bus Depot and Loyang Bus Depot, supplied by NARI.

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Exterior

The Yutong E12 buses were built by Yutong in Zhengzhou, China with integral bodywork, and shipped to Singapore as a Complete Built-Up (CBU) vehicle.

The bus is painted in LTA’s standardized Lush Green base livery with ‘Eco Bus | Zero Emissions, Cleaner Air’ decals on both sides. In addition, only SG3098L is stickered with an advert promoting it as an electric bus. Other buses were progressively stickered in March 2022.

The roof houses 6 battery banks split into two compartments. Batteries are supplied by Contemporary Amperex Technology Co., Limited (CATL), also from China.

The Cling EZDS-06 air-conditioning system mounted in the middle of the roof. Typical for full-electric buses, the air-conditioning units rely on electrically-driven compressors, tapping on the bus’ high-voltage DC power supply (shared with traction motors) via its own set of inverters.

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Interior

The bus features 28 permanent seats. Being a low-floor bus, the bus offers step-free access from entry/exit doors until the last row of seats. Mood lighting in the bus cabin is offered in 3 colours—Dark Blue, Sky Blue and Orange.

Like most single-deck buses in Singapore, the Yutong E12 buses are configured with two doors: an entrance door at the front, and an exit door in the middle. The entrance doors are conventional inward-swinging leaf doors, while the exit doors are outward-swinging plug doors. They are supplied by SMC Transit.

Single seats are fitted above the front wheel arches. The front right wheel arch does not feature any forward-facing seats; it is instead occupied by a large electronics cabinet.

The entrance door is no longer fitted with a centre pole as per older buses for the benefit of stroller boarding. Signs indicating no standing on the door movement area are printed on the floor.

The bus features two wheelchair bays, both located opposite the exit door. They each accommodate one passenger-in-wheelchair (PIW), and are equipped with USB charging ports. Foldable armrests and a stroller restraint system is provided for wheelchair users and the securing of prams respectively.

Seating

Seats were supplied by Ster of Poland (Model: New City) in Blue, with priority seats in Red.

Priority seats, which are indicated in red seat covers, occupy the seats between entry and exit doors, as well as the first row behind the exit door. The red colour theme extends to the wheelchair backrests.

A small metal storage rack is provided beside both rear-facing front priority seats for the benefit of commuters with bags or groceries.

Grab poles and handgrips are located on both sides of the aisle. All seats also have handgrips to provide commuters with additional support.

Yellow bus stopping bell-pushes are located around the bus cabin, mounted to stanchion poles. Some stanchion poles have areas around the bell also coated in yellow to aid with visual identification. Emergency hammers are located on pillars in-between windows.

The rear section of the bus sits four abreast in forward-facing and rear-facing seats. One row of seats is eliminated from a typical single-deck bus design to accommodate rear-mounted battery packs and powertrain components.

 

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Continued on Page 2:

• Driver’s Compartment
  • Collision Warning System
• Features in-depth
  • Wheelchair Bay
  • Passenger Information Display System (PIDS)
  • Mood Lighting
  • USB Charging Ports
  • Doors & Passenger Counter
• Gallery