BYD B12A03 (LTA Trial Bus)

BYD B12A03
Bus 265 - SBS Transit BYD B12A03 (SG4013A)BYD B12A03 (SG4013A)
Manufacturer BYD Auto Industry
Bodywork BYD (integral)
Years in operation 2023-
Operators SBS Transit
Technical Data
Length 11.98 m
Motor BYD AC Synchronous Motor
Battery BYD Blade LFP (433.45 kWh)
Accessibility Low Floor
Emission Standard Zero tailpipe emissions

The BYD B12 is an electric single-deck city bus offered by Chinese bus manufacturer BYD Auto Industry (比亞迪). As of 2023, it is BYD’s flagship electric city bus, superseding the highly successful BYD K9.

A 3-door BYD B12A03 demonstrator unit was offered to the Land Transport Authority (LTA) for revenue service trials. Registered as SG4013A, this specific unit was also previously exhibited at SITCE 2022, an industry trade show held in Singapore.

In line with 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.

Registration & Rollout

The bus was registered on 25 October 2023 to SBS Transit, which operates the bus from Seletar Bus Depot. It would be recharged at existing 150kW DC (CCS Type 2) electric bus chargers supplied by ABB, which were installed as part of the BYD K9 rollout.

The bus registration number, SG4013A, follows in a series of LTA trial buses (SG400x).

On 14 January 2024, the bus made its revenue service debut on Bus Service 265. The bus was later deployed on Bus Service 138 on 16 April 2024.

⚠ Looking for the ComfortDelGro Bus? ⚠

For the version of this bus operated by private bus operator ComfortDelGro Bus, visit this article: BYD B12A03 [Private Bus].


BYD’s ‘B-series’ electric bus range was launched 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. These new buses supersede their older K-series counterparts, the longest-running of which was the BYD K9, which was first launched in 2010 and had found tremendous success in both domestic and overseas markets, including previous deliveries to Singapore.

According to BYD, numerous technical improvements were made to improve efficiency, such as new-generation wheel hub motors which are 6% more energy efficient, and a lightweight aluminium body frame that reduces vehicle weight by 10%. Upgraded traction batteries are paired with a new battery management system with improved monitoring capabilities. All traction batteries are also water-cooled to an optimal working range of 25~35°C, preserving the operating range between charges and battery longevity.

BYD also touts ergonomic improvements for both drivers and passengers. The driver’s cab features a digital dashboard with integrated controls and comfort features such as ventilated seats with massage features. The passenger cabin has window areas increased by 10% with fewer stanchion poles in the way of passenger movement, and a sunroof can also be configured. Finally, BYD offers driver assistance features such as EPAM (pedal misapplication assistance system), collision detection and lane departure warnings, driver fatigue monitoring, and so forth.

Outside of China, 30 buses were delivered to the TransJakarta bus network in Jakarta. Hong Kong bus operator Kowloon Motor Bus also took delivery of 16 BYD B12A units in late 2021.

BYD Blade Battery

The BYD B12A03 model is also the first BYD bus equipped with BYD’s proprietary Blade battery. Unveiled in 2020, it uses Lithium Iron Phosphate (LFP) chemistry and is optimized for energy density and safety.

According to BYD, the Blade battery is over 50% more space efficient than conventional LFP battery packs. Blade batteries were tested in extreme conditions, such as nail penetration, crushing, heating and overcharging, none of which resulted in a thermal runaway (fire or explosion).

At Busworld Europe 2023, BYD unveiled an improved BYD B12 bus with Blade batteries integrated into the chassis structure, for a maximum capacity of 500 kWh. Silicon carbide (SiC) motor controllers and wheel hub hairpin motors were used to further increase energy efficiency.

Singapore Market

BYD’s existing presence in Singapore includes 20 BYD K9 (Gemilang) buses procured by LTA with another BYD K9RC double-deck prototype unit on trial with LTA. ComfortDelGro also operates two BYD coaches, a BYD C9 and a BYD C8.

As for the broader electric bus market in Singapore, the Land Transport Authority is rapidly electrifying the public bus fleet. Half of all public buses will be electric by 2030, which is about 3,000 buses.

In 2022, ComfortDelGro Bus took delivery of 10 BYD B12A03 single-deck buses, configured with three passenger doors. The LTA trial bus (SG4013A) would also arrive in Singapore that same year.

LTA Trial Bus

The LTA trial bus was initially delivered to Singapore in 2022 (Chassis Number: LC06S44RXN4000100) and subsequently exhibited at the LTA-UITP Singapore International Transport Congress & Exhibition (SITCE) 2022. Detailed coverage is on Page 2 of this article.

After the conclusion of SITCE 2022, the bus underwent retrofitting works in preparation for revenue service trials with LTA. This involved the installation of the Common Fleet Management System, fare collection equipment, and repainting to LTA’s standardised Lush Green livery. The EDS/PIDS/ADAS systems were also replaced with different models, common to LTA buses.

Revenue service entry

On 25 October 2023, the bus was registered to SBS Transit, with the registration number SG4013A.

Revenue service commenced on 14 January 2024, with the bus deployed on Bus Service 265.

On 16 April 2024, the bus was deployed on Bus Service 138.

Production Batch

In November 2023, BYD was awarded an LTA contract for 240 single-deck 3 door electric buses. According to BYD, these buses would be built on the B12 platform, and the exact model / bodywork design remains to be confirmed.


BYD B12A03 – Specifications
Length × Width × Height: 11980 mm × 2550 mm × 3270 mm
Wheelbase: 5900mm
Curb Weight: 13,500 kg
Max Gross Weight: 18,850 kg
Electric Motor
BYD Permanent Magnet Synchronous Motors (×2)
Maximum power/torque of 300 kW (150 kW × 2) / 1100 Nm (550 Nm × 2) )
Regenerative braking capabilities + Front and rear disc brakes
BYD Blade battery (Capacity 433.45 kWh)
Lithium Iron Phosphate (LFP) chemistry; liquid-cooled with BTMS
Charged via 130 kW×2 DC plug-in chargers (CCS Type 2 connector); 2-3 hours full charge
380 km range on full charge (SORT test); full charge duration of 2-3 hours
BYD Integral bodywork (Lightweight aluminium structure)
EDS Luminator ULTIMA Electronic Display Sign (EDS)
Orange LED Matrix design. Luminator Basic driver controller.
PIDS Luminator SMART Passenger Information Display System (PIDS)
Interior-facing LCD screen (29”) and exterior-facing LCD screen + LED Text Display
APCS TNT Surveillance T-APC Automatic Passenger Counters
Driver Assistance TNT Surveillance T-Guard
– Forward collision warning system & lane departure warning (T-FA Front Alert Camera)
– Side collision warning system (T-SA Side Alert Cameras)
– Anti-Fatigue system (T-DA Driver Alert Camera)
– Surround view camera system (T-A.I. 360°)
Passenger Capacity 28 Seated + 55 Standing = 83 Passengers
2 Wheelchair Bays
Other Specifications • Ster 8MA seats
Ventura doors
SONGZ ESD-VI-BNSD air-conditioning​
• USB Charging Ports
• Aircharge Nylon wireless surface chargers
• Camera mirror system

Overview & Exterior

The BYD B12 was built by BYD in Hangzhou (China) and delivered to Singapore as a complete built-up unit.

The exterior design features a streamlined roof element where traction batteries and air-conditioning components are integrated. According to BYD, the coefficient of wind resistance is lower than 0.45, which effectively reduces the energy consumption of the whole vehicle by 1%-2%. The lightweight aluminium body makes the bus 300-500 kg lighter than electric buses of similar size and range.

The full-low-floor design with three passenger doors is enabled by the bus’ compact electric drivetrain, with the rear drive axle powered by two 150 kW direct-drive in-axle motors.


The low-floor BYD B12 offers step-free access across the entire length of the bus. It features a three-door configuration, with an entrance door at the front, an exit door in the middle, and a second exit door at the very rear of the bus.

Seats are supplied of the Ster 8MA model, and upholstered in blue and red, with red seats intended as priority seats.


Both wheelchair bays are located opposite the exit door. Each bay accommodates one passenger-in-wheelchair (PIW), and the wheelchair backrest contains a foldable seat that doubles as a rear-facing seat. These seats do not contribute to the licensed seating capacity of the bus.

In addition, a pivoting handlebar is integrated with each wheelchair backrest. It can be manually deployed and stowed depending on the passenger’s needs.

Both wheelchair bays are located opposite the exit door. Each bay accommodates one passenger-in-wheelchair (PIW), and the wheelchair backrest contains a foldable seat that doubles as a rear-facing seat. These seats do not contribute to the licensed seating capacity of the bus. USB Charging ports are also provided at both bays.

In addition, a pivoting handlebar is integrated with each wheelchair backrest. It can be manually deployed and stowed depending on the passenger’s needs.

The three-door bus design promotes the one-way flow of passengers towards the rear of the bus, allowing for faster boarding and alighting. The BYD B12 comes with a wide double-leaf rear door for greater ease of alighting from the rear. A floor step is provided for passengers accessing the last row of seats, despite being positioned at the same height as the facing seats in front.

Wall-mounted USB charging ports are provided at each seat, rated at 2.1 A output. There are also wireless surface chargers (Aircharge Nylon model) positioned on top of the wheel arches.

The driver’s cab features standard LTA equipment – e.g. Trapeze Common Fleet Management System (CFMS) and New Onboard Bus Equipment (NOBE). A camera mirror system was fitted several weeks after its launch on revenue service, with exterior cameras feeding into two vertical display screens positioned near the driver’s blinds.

Gallery (LTA Trial Bus):
Gallery (Interior):

LTA Trial Bus Series:
Registration Type Bus Model
SG4001J Electric SD 2 Door (Low Entry) BYD K9
SG4002G Diesel Euro V SD 3 Door (Low Entry) MAN Lion’s City SD – 3-door Concept Bus
SG4003D Diesel Euro 6 DD 2 Door Volvo B8L
SG4004B Hybrid SD 2 Door Mercedes-Benz Citaro hybrid
SG4005Z Electric DD 2 Door BYD K9RC
SG4006X Electric SD 3 Door CRRC TEG6125BEV03
SG4007T Electric SD 3 Door Volvo BZL
Electric SD 3 Door Ankai G9
SG4010H Electric SD 3 Door Zhongtong LCK6126EVG
SG4012C Electric SD 3 Door FTBCI FBC6120BRS7
SG4013A Electric SD 3 Door BYD B12A03


See Also:


Continued on Page 2:
  • SITCE 2022 Display Bus

12 thoughts on “BYD B12A03 (LTA Trial Bus)

  • 25 January 2024 at 12:51 PM

    Actually, very considerate of them to put all the electric buses, currently limited in numbers, mostly at feeder bus routes, such as 282 at Clementi.

  • 23 January 2024 at 10:19 PM

    I have been taking the BYD Double Decker variant on 189 for the past one week. The interior feels very ergonomic and comfortable. Looking at the pictures of the BYD Single Decker variant, it looks the same. Am glad that this would become a standardized interior design of public buses moving forward.

  • 25 November 2023 at 10:14 PM

    Heard this bus will go to 265 like the BYD K9s

    • 14 January 2024 at 9:23 AM

      Confirmed. Rolled out today on 265


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