The Volvo S80 2.4 Bi-Fuel, produced from 2003 to 2006, represents a unique offering within the second-generation (1998-2006) S80 lineup. This variant combined a conventional 2.4-liter petrol engine with the capability to run on Compressed Natural Gas (CNG), catering to markets with incentives for alternative fuel vehicles, particularly in Europe. Positioned as a mid-range option, it offered a balance between performance and economy, appealing to buyers seeking a comfortable, spacious sedan with reduced emissions and fuel costs when operating on CNG. The facelifted S80, introduced in 2003, brought updated styling and minor mechanical refinements to the model.
Technical Specifications
| Brand | Volvo |
| Model | S80 |
| Generation | S80 (facelift 2003) |
| Type (Engine) | 2.4 (140 Hp) Bi-Fuel CNG Automatic |
| Start of production | 2003 |
| End of production | 2006 |
| Powertrain Architecture | Internal Combustion engine |
| Body type | Sedan |
| Seats | 5 |
| Doors | 4 |
| Fuel consumption (economy) – urban | 14.9 l/100 km (15.8 US mpg, 19 UK mpg, 6.7 km/l) |
| Fuel consumption (economy) – extra urban | 7.6 l/100 km (30.9 US mpg, 37.2 UK mpg, 13.2 km/l) |
| Fuel consumption (economy) – combined | 10.1 l/100 km (23.3 US mpg, 28 UK mpg, 9.9 km/l) |
| Fuel consumption (economy) – combined (CNG) | 8.7 kg/100 km |
| CO2 emissions | 246 g/km |
| CO2 emissions (CNG) | 187 g/km |
| Fuel Type | Petrol / CNG |
| Acceleration 0 – 100 km/h | 11.4 sec |
| Acceleration 0 – 62 mph | 11.4 sec |
| Acceleration 0 – 100 km/h (CNG) | 11.9 sec |
| Acceleration 0 – 60 mph (Calculated) | 10.8 sec |
| Maximum speed | 200 km/h (124.27 mph) |
| Emission standard | Euro 4 |
| Weight-to-power ratio | 11.2 kg/Hp, 89.6 Hp/tonne |
| Weight-to-torque ratio | 7.1 kg/Nm, 140.8 Nm/tonne |
| Power | 140 Hp @ 4500 rpm |
| Power per litre | 57.5 Hp/l |
| Power (CNG) | 140 Hp @ 5800 rpm |
| Power per litre (CNG) | 57.5 Hp/l |
| Torque | 220 Nm @ 3300 rpm (162.26 lb.-ft. @ 3300 rpm) |
| Torque (CNG) | 192 Nm @ 4500 rpm |
| Engine layout | Front, Transverse |
| Engine Model/Code | B5244SG |
| Engine displacement | 2435 cm3 (148.59 cu. in.) |
| Number of cylinders | 5 |
| Engine configuration | Inline |
| Cylinder Bore | 83 mm (3.27 in.) |
| Piston Stroke | 90 mm (3.54 in.) |
| Compression ratio | 10.3:1 |
| Number of valves per cylinder | 4 |
| Fuel injection system | Multi-port manifold injection |
| Engine aspiration | Naturally aspirated |
| Valvetrain | DOHC |
| Engine oil capacity | 5.8 l (6.13 US qt, 5.1 UK qt) |
| Coolant | 8 l (8.45 US qt, 7.04 UK qt) |
| Kerb Weight | 1562 kg (3443.62 lbs.) |
| Max. weight | 2060 kg (4541.52 lbs.) |
| Max load | 498 kg (1097.9 lbs.) |
| Trunk (boot) space – minimum | 460 l (16.24 cu. ft.) |
| Trunk (boot) space – maximum | 1126 l (39.76 cu. ft.) |
| Fuel tank capacity | 29 l (7.66 US gal, 6.38 UK gal) |
| CNG cylinder capacity | 17.6 kg |
| Max. roof load | 100 kg (220.46 lbs.) |
| Permitted trailer load with brakes (12%) | 1800 kg (3968.32 lbs.) |
| Permitted trailer load without brakes | 750 kg (1653.47 lbs.) |
| Permitted towbar download | 75 kg (165.35 lbs.) |
| Length | 4822 mm (189.84 in.) |
| Width | 1832 mm (72.13 in.) |
| Height | 1452 mm (57.17 in.) |
| Wheelbase | 2791 mm (109.88 in.) |
| Front track | 1570 mm (61.81 in.) |
| Rear track | 1548 mm (60.94 in.) |
| Front overhang | 964 mm (37.95 in.) |
| Rear overhang | 1067 mm (42.01 in.) |
| Drag coefficient (Cd) | 0.28 |
| Minimum turning circle | 11.6 m (38.06 ft.) |
| Drivetrain Architecture | ICE to Front Wheels |
| Drive wheel | Front wheel drive |
| Number of gears and type of gearbox | 5 gears, automatic transmission |
| Front suspension | Independent type McPherson |
| Rear suspension | Independent multi-link suspension |
| Front brakes | Ventilated discs, 288 mm |
| Rear brakes | Disc, 288 mm |
| Assisting systems | ABS (Anti-lock braking system) |
| Steering type | Steering rack and pinion |
| Power steering | Hydraulic |
| Tires size | 215/55 R16; 225/50 R17 |
| Wheel rims size | 7J x 16; 7J x 17 |
Powertrain & Engine Architecture
The heart of the S80 2.4 Bi-Fuel is the Volvo B5244SG engine, a 2.4-liter inline-five cylinder powerplant. This engine is a naturally aspirated design featuring multi-port fuel injection and a double overhead camshaft (DOHC) valvetrain. The engine’s ability to run on both petrol and CNG is achieved through a dedicated CNG fuel system that switches operation based on fuel availability and driver selection. When running on CNG, the engine management system adjusts parameters to optimize combustion for the alternative fuel. The engine produces 140 horsepower at 4500 rpm and 220 Nm (162 lb-ft) of torque at 3300 rpm on petrol. When running on CNG, power output remains the same, but torque is slightly reduced to 192 Nm (142 lb-ft). The engine is paired with a five-speed automatic transmission, designed for smooth and comfortable shifting.
Driving Characteristics
The 2.4 Bi-Fuel S80 offered a comfortable, albeit not particularly sporty, driving experience. The automatic transmission, while smooth, prioritized fuel efficiency over rapid acceleration. The 0-60 mph time of around 10.8 seconds reflects this focus. Compared to the higher-output petrol versions of the S80, such as the 2.9 or T6 models, the 2.4 Bi-Fuel felt noticeably slower. However, the CNG mode provided a different driving character, with slightly reduced responsiveness due to the lower torque output. The gear ratios were optimized for cruising, making it a suitable vehicle for long distances. The suspension, tuned for comfort, absorbed bumps well, but didn’t offer the same level of handling precision as sportier alternatives.
Equipment & Trim Levels
The S80 2.4 Bi-Fuel typically came with a respectable level of standard equipment. This included features like automatic climate control, power windows and mirrors, a CD stereo system, and ABS brakes. Interior upholstery was generally cloth, with leather options available as an upgrade. Trim levels varied by market, but generally offered options for alloy wheels, a sunroof, and upgraded audio systems. Safety features, a hallmark of Volvo, were comprehensive, including front and side airbags.
Chassis & Braking
The S80 2.4 Bi-Fuel utilized an independent McPherson strut suspension in the front and an independent multi-link suspension in the rear, providing a comfortable ride. Braking duties were handled by ventilated discs at the front and solid discs at the rear. ABS was standard, enhancing braking performance and stability. The chassis was designed to prioritize comfort and safety, rather than outright handling prowess. Stabilizer bars were fitted to both axles to reduce body roll during cornering.
Market Reception & Comparison
The S80 2.4 Bi-Fuel was primarily targeted at environmentally conscious buyers and those seeking to reduce their fuel costs in regions with CNG infrastructure and incentives. Critics generally praised the vehicle’s comfort, spaciousness, and safety features. However, the performance was often seen as adequate rather than exciting. Compared to the petrol-only S80 variants, the Bi-Fuel model offered comparable fuel economy on petrol, but significantly lower running costs when utilizing CNG. The reliability of the B5244SG engine was generally good, although the added complexity of the CNG system introduced potential maintenance concerns.
Legacy
The Volvo S80 2.4 Bi-Fuel represents an interesting chapter in Volvo’s history, demonstrating the company’s early commitment to alternative fuel technologies. While CNG never achieved widespread adoption in many markets, the S80 Bi-Fuel provided a viable option for those seeking a more sustainable transportation solution. Today, these vehicles are relatively rare, and well-maintained examples are sought after by enthusiasts and those interested in classic Volvo models. The B5244SG engine is known for its durability, and with proper maintenance, these S80s can continue to provide reliable transportation for years to come. The CNG system, however, may require specialized servicing due to its age and limited availability of parts.


