EnergyDecentral: Successful MAN gas engine E3268 in variant with 320 kW

40% electrical efficiency in natural gas operation; natural gas variant with 250 mg/Nm3 NOx; meets the requirements of Technical Instructions on Air Quality Control (TA Luft) ½ with only an oxidation catalyst

At EnergyDecentral 2018, MAN Engines will be presenting its gas engine E3268 in the 320 kWmech variant for the first time at 50 Hz operation. The MAN E3268 LE242 is based on the E3268 with 370 kWmech, which was introduced in 2013, and has therefore been tried and tested in the field hundreds of times over. The V8 engine is available in a natural gas-optimised variant with a compression ratio of ε 12 : 1 and can also be used with biogas with a compression ratio of ε 13.6 : 1. Potential uses in current-regulated CHP applications (combined heat and power) range from the industrial and commercial to the municipal and recreational sectors.

The new E3268 LE242 is designed as forced induction four-stroke internal combustion gas engines, with eight cylinders arranged in the shape of a V. Thanks to a cylinder bore of 132 mm and a stroke of 157 mm, the E3268 LE242 offers 17.2 L of cylinder capacity. To achieve an output of 320 kW at 1500 rpm, the charge exchange has been significantly optimised. This has a positive effect on the energy efficiency, which can be up to 41.7%mech in the natural gas variant. “This excellent mechanical efficiency rate enables us to achieve the magic number of 40% energy conversion efficiency. In some countries that's worth hard cash due to subsidies,” says Günther Zibes, Head of Power at MAN Engines.

The E3268 LE242 with 320 kWmech will replace the E2848 LE322 from the previous series and so close the power gap in the portfolio of MAN Engines among turbo engines between 220 and 370 kWmech. The tried-and-tested data logger with standardised sensors and cable harness offers an additional benefit for customers. Via a CAN interface, important parameters such as the coolant, oil and exhaust gas temperature, as well as the charge pressure and oil pressure, can be provided for the system controls with minimum effort.

The E3268 LE242 is well-equipped for future emissions requirements thanks to a variant with nitrogen oxide levels of 250 mg/Nm3 NOx (5% O2). At the same output of 320 kWmech, the MAN gas engine - equipped only with an oxidation catalyst - meets the requirements of the Technical Instructions on Air Quality Control (TA Luft) ½.

For markets with a 60-Hz mains frequency, MAN Engines also offers an operating variant of E3268 LE242 for natural gas with a rated speed of 1,800 rpm. This has an output of 340 kWmech and achieves a mechanical efficiency rate of 40.3 % and a thermal efficiency rate of 48.2 %, or 88.5 % in total.

The E3268 LE242 will be available from the first quarter of 2019 and will be presented for the first time at EnergyDecentral, the international trade fair for innovative energy supply, in Hanover. It can be seen from 13 to 16 November 2018 at MAN Engines Stand D14 in Hall 24.

E3268 LE242

    Natural Gas Special Gas
  Unit 50 Hz
(Variants with 500 and 250 mg/Nm3 NOx)
60 Hz 50 Hz
Arrangement/number of cylinders   V8 V8 V8
Bore mm 132 132 132
Stroke mm 157 157 157
Displacement l 17,2 17,2 17,2
Standard power
(in accordance with German Industrial Standard DIN ISO 3046 Part 1)
kW 320 340 320
Rated speed rpm-1 1500 (50 Hz) 1800 (60 Hz) 1500 (50 Hz)
Air-fule ratio λ 1,70 1,70 1,54
Compression ratio ε 12:1 12:1 13,6 : 1
Exhaust heat based on 120°C
(at 100% load)
kW 181 204 206 177
Efficiency mecahnical
(at 100% load)
% 41,7 39,2 40,3 41,9
Efficiency thermal % 47,5 50,0 48,2 89,5
Efficiency total % 89,2 89,2 88,5 1620
Engine length mm 1620 1620 1210
Engine width mm 1210 1210 1422
Engine height mm 1422 1422 1497
Weight (dry) kg 1497 1497 500
Exhaust status NOx
(with 5% exhaust-gas oxygen)
mg/Nm3 500 250 500  
Combustion   lean lean lean

As at: 18.04.2018