IN late April, Mercedes met the interna-tional press to give opportunities to

those who had not yet took a ride with the main Mercedes-Benz models making its way through the streets of Mannheim, Germany. One could try a wide range of busses from the Travego L to the Safety Coach version, from the Sprinter City 65 to the Capacity L. But the icing on the cake was the Citaro NGT powered by compressed natural gas.The Citaro NGT (Natural Gas Technology), presented at Kortijk Busworld in October 2015, proposes a new look and new features offering many advantages compared to its predecessor

Length mm 12,135 Width mm 2,550 Height mm 3,389 Wheelbase mm 5,900 Front overhang mm 2,805 Rear overhang mm 3,430 Turning circle mm 21,214 Capacity gas system litres 1,360

DIMENSIONS

BusToCoach on-line Magazine - June 2016 MERCEDES - CITARO NGT

THE GAS-POWERED

ALTERNATIVE èè

€ 309,000Price in Germany

(excl. VAT).

T he Citaro NGT uses the re-cent improvements made to

the Citaro range, such as the front rounded end, the collision prevention system for the driver, the low side window line, the LED headlights (optional). The interior is welcoming and bright. The vehicle tested in Mannheim offered an example with the flo-oring in dark brown wood look, the internal LED lighting, the access courtesy lights, the 29-inch TFT monitor and five char-ging stations for smartphones. The City Star Eco upholstery is produced in-house. Among the news, there are the folding seats of the latest generation: larger and available (includi-

ng) in double or mother/child version. The driving position is raised and features a VDA ergo-nomic instrumental panel. The cockpit is ventilated and is se-parately air-conditioned. There

is a large central color display, the swiveling Grammer Linea/Tourea adjustable driver’s seat with pneumatic shock absor-ption and lumbar support, the electromagnetic driver’s door

and heated window. Four vi-deo cameras gives a complete surveillance of the passenger compartment and access. The rear-view mirrors are electri-cally adjustable and heated.•

AUTISTA Seats/Standing n. 28/64+1 Internal heigth mm 2,313 Aisle heigth mm 370 Entrances width mm 1,210 Comfort Seats type City Star Eco Driver seat Grammer A.C separate areas Heater convectors Glazing double Roof Hatches 2 electric Folding ramp manual

INTERIORS

starting from lower fuel consumption (15-20%) and CO2 emissions (up to 10% less compared to diesel), to the improved smooth-running with even lower noise emissions undercut by up to 4 dB (A), with bigger intervals for changing the engine oil and spark plugs extended to 60,000 kilometres. The vehicle was fitted with the new M 936 six in-line-cylinder gas engine, which is

based on the OM 936 turbodiesel.Another advantage of the Citaro NGT solo bus is the increased capacity that allows transpor-ting 96 instead of previous 93 passengers, while the articulated bus version can carry up to 153 instead of previous 149 passengers. All this is due to the vehicle’s reduced weight, in addition to the more compact engine almost 25 percent

lighter than the predecessor engine with a di-splacement of 12.0 litres, the considerably in-creased capacity of the gas cylinders (from 190 to 227 litres each) and the consequent reduction in gas cylinders number (one less with weight savings of 15 to 45 kg). The newly developed gas cylinders are made of composite material with a plastic core, a casing is made of carbon

fiber and an additional glass fiber is a new fea-ture. The gas cylinders are positioned above the front axle on the solo bus (above the centre axle on the articulated bus) with two different covers accommodating either four to six gas cylinders or seven to eight.But let’s get down to the Mannheim drive test. The Citaro NGT has been tested over a distan-

èè

Welcomingand pratical

T he heart of the Citaro NGT is the new M 936 gas engine

based on the OM 936 turbodiesel. Mounted vertically, this compact power unit weighs just 747 kg including the primary catalytic converter. It is a 7.7-litre engine, delivering 222 kW (302 hp) and

able to achieve a constant maxi-mum torque of 1,200 Nm be-tween 1,200 and 1,600 rpm. The cylinder block and four-valve cylinder head were adopted from the diesel engine and adapted for operation on CNG. On the con-trary, the turbocharger, charge-air

ducting, ignition and injection system have been newly devel-oped. Due to the practically soot-free combustion, the engine does not require the SCR technology with AdBlue injection or a partic-ulate filter. In natural gas engine the exhaust gases are purified by

means of a three-way catalyst converter. CO2 emissions also fell by 10% compared to diesel, and in case of using biomethane they become CO2 neutral. The gearbox is (equipped) fitted with a torque converter, and the cus-tomers can choose between the

ZF or Voith brand. The test vehi-cle in Mannheim was fitted with the six-speed ZF Ecolife. The drive ratio is slightly shorter than the diesel and corresponds to i = 5.82 for the 12-metre version and i = 6.98 for the articulated bus. The ESP is upon request. •

Engine M 936 G Displacement 7,698 c.c. P. cv(kW)/rpm 302 (222)/2,000 Torque Nm/rpm 1,200/1,200-1,600 Emissions Euro VI/Converter Gearbox ZF 6AP 1200B Disc brakes Ebs/ESP, Retarder Suspensions full pneumatic Tyres 295/80 R 22.5

TECHNIQUE

Nm

1,200

1,000

800

kW

220

210

185

160

135

110

M 936 G Euro VI

1,000 1,200 1,400 1,600 1,800 2,000 rpm/min

More articles about Mercedes: www.bustocoach.com/en/node/473/articoli-costruttore-europa

Compact and clean

ce of (a good 12 km among industrial areas, high-speed sections and residential areas at low speed. The vehicle showed a good capacity of acceleration that corresponds to the characteri-stics of its diesel counterpart OM 936. The vehi-cle moved gently but swiftly departing from the bus stops. Then, the bus coped effortlessly with both the climb and the increase in speed in the

area with the limit of 70 km/h, also showing a slight variation of noise emissions. The front axle with independent wheel suspension gently cushions any bumps in the road, and the vehi-cle remained unperturbed even crossing over the railway that normally gives a thorough shaking. Another talent was shown when entering the parking place, where the rigid bus performed

the necessary turning manoeuvres.The Citaro NGT reached the market after three years of arduous tests under the most demandi-ng conditions, undergoing altitude testing at ele-vations of up to 1,600 m with a total distance of 130,000 kilometres covered by three test vehi-cles. Full series production started this spring.The Citaro NGT however represents the Daim-

ler transitional solution aimed at the zero-emis-sion buses. Developments in progress include a compact hybrid component for the Citaro with diesel engine and the Citaro E-CELL running exclusively on electric power, whose premie-re has been announced for 2018. This will be followed by the Citaro F-CELL with fuel-cell drive. •

Power

Torque