BYD B12DS 3-Door double-deck bus for Singapore

The BYD BC12A05 (marketed as BYD B12DS) is a battery-electric double-deck city bus manufactured by BYD Auto Industry (比亞迪). Designed specifically for the Singapore market, it is a right-hand-drive vehicle equipped with three doors and two staircases.

One such bus was exhibited at the LTA-UITP Singapore International Transport Congress & Exhibition (SITCE), held in November 2024.

In line with the Land Transport Authority (LTA)’s ongoing efforts to rapidly electrify the public bus fleet, half of all public buses will be electric by 2030. Detailed coverage of this rollout can be found at Electric Buses in Singapore.

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Bus Model background

BYD launched its ‘B-series’ electric bus range on 29 July 2020, comprising the single-deck BYD B10 and BYD B12 of 10 and 12-metre lengths, and the BYD B12D 12-metre double-deck bus.

The BYD B12 is powered by twin wheel-hub hairpin motors that are directly connected to the driven wheels, maximizing available cabin space by eliminating the need for a transmission and driveshaft. A ‘6-in-1 electronic controller’ with SiC elements simplifies the vehicle’s electronics, by combining 2 electric motor controls, a steering control unit, an air compressor controller, a DC-DC converter and a power distributor unit into a single module.

BYD also offers the bus with Blade batteries, a proprietary lithium iron phosphate (LFP) battery design optimised for energy density and safety. These batteries are water-cooled to maintain their optimal working range, and paired with a battery management system for performance monitoring. Some of these batteries can also integrated into the chassis as an option, which further improves battery space utilization and lowers the bus’ centre of gravity.

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Units in Singapore

A BYD B12DS bus was first seen in Singapore in October 2024, delivered in a Lush Green livery. This unit may be a demonstration vehicle offered to the LTA for revenue service trials.

Another unit was displayed at the LTA-UITP Singapore International Transport Congress & Exhibition (SITCE) in November 2024, this time in a white base colour with a red advertising wrap. It is unclear whether the SITCE display unit is the same one seen in October or a different unit.

SITCE 2024

At the SITCE 2024 exhibition, the BYD B12DS was showcased in its red advertising wrap over a white base coat, prominently displaying the bus’s key specifications. Additionally, a BYD B12DS chassis was also presented.

The chassis plate identifies the exhibited bus as a BYD BC12A05 model, with the chassis number LC04S44M6R0000006.

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Specifications

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Layout

The BYD B12DS is a full-low-floor double-deck bus with three doors and two staircases. The full-low-floor layout optimizes passenger flow, as the rear staircase leads directly to the third door, facilitating a smoother exit for upper-deck passengers through the rear door.

LTA’s preference for three-door buses is evident in previous orders, including a 2019 order of 100 double-deck buses with a three-door, two-staircase layout. A 2023 order for 360 single-deck electric buses also required a three-door layout.

The BYD B12DS can accommodate at least 120 passengers.

Lower Deck

The lower deck of the bus has 16 seats, and 2 wheelchair bays (each with a foldable seat). The design features a fully low-floor aisle from the entrance to the rear third door, enhancing accessibility.

Fainsa Punt passenger seats with headrests are used, featuring blue and red upholstery. Stanchion poles have yellow-coated areas to help with visual identification of bell attachment points.

The entrance doors are inward-swinging leaf doors, while both exit doors use a sliding plug design.

Accessibility

LTA specifications require two wheelchair bays for passengers travelling in wheelchairs or using personal mobility aids. An automatic wheelchair ramp at the middle door provides accessibility.

Each wheelchair bay backrest also contains a foldable seat that doubles as a rear-facing seat. A side handlebar can be manually deployed and stowed depending on the passenger’s needs. This swivel handlebar design first appeared on ADL E500 3-door buses.

Staircases

The bus is equipped with 2 staircases: the front staircase is located behind the driver’s cab, and the second is positioned at the rear, providing direct access to the third door.

This layout allows passengers to quickly exit from the upper deck, making alighting more convenient and efficient. Most passengers on the lower deck typically exit through the middle door.

Upper Deck

The upper deck seats 48 passengers.

Driver Cabin

The driver’s cabin is outfitted with a TNT Surveillance Advanced Driver Assistance System (ADAS) and Anti-Fatigue System, which integrates lane departure warning, forward collision warning, distance monitoring, pedestrian detection, side blindspot monitoring, and driver fatigue/distraction monitoring features into a single system. A single overhead-mounted touchscreen display is used as the display screen and controller.

Additionally, the bus uses a camera-based mirror system instead of traditional wing mirrors (model: TNT Surveillance T-DM821). Two vertical CCTV monitors replicate the view of wing mirrors, while a third overhead monitor provides an overhead view of the front and front-left blind spots.

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BYD B12DS chassis

A BYD B12DS chassis (Chassis Number: LC04S44M3RE000001) was exhibited at SITCE 2024.

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See Also:

• BYD K9 (Gemilang)
• BYD K9RC
• BYD B12A03 (LTA Trial Bus)
• BYD B12A03 (Private Bus)
• BYD BC12A04

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References:

• BYD B12DS Specifications (as at SITCE 2024) [Accessed 6 Nov 2024]

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