The most powerful natural-gas-driven saloon ever
By Mike Hanlon
February 8, 2005
February 9, 2005 The Mercedes-Benz E 200 NGT switches from natural gas to petrol at the press of a button, does 227kmh and performs on par with the E200 KOMPRESSOR in either mode, and can halve running costs if run on natural gas alone. Throw in Mercedes exceptional retained value resale figures and the equation looks like a winner for when the right-hand drive models become available mid-year.
The Mercedes-Benz E 200 NGT first became available on Germany's roads in the European spring of 2004, with availability extending to Austria, Italy, Sweden and Switzerland in the following months. Now this dual-fuel, clean-running variant of the E-Class is to be made in right-hand-drive and will become available for the Asian market from June. The most significant selling feature of the E200 NGT is that it halves running costs while still producing 120 kilowatts of power, making it the most powerful natural-gas-driven saloon currently in production.
The E 200 NGT (Natural Gas Technology) was developed in the Mercedes-Benz Technology Centre on the platform of the E 200 KOMPRESSOR. The four-cylinder powerplant has a power rating of 120 kW/163 hp and generates a peak torque of 240 Newton metres, figures which are both on a par with the E 200 KOMPRESSOR.
Thanks to the elaborate solutions which have been used to integrate the additional technical componentry, power delivery, comfort, quality and safety have not been compromised in any way aboard the E 200 NGT.
The E 200 NGT with its bi-fuel petrol/natural-gas power unit complies with the same stringent EU 4 emissions limits met by the petrol-powered E 200 KOMPRESSOR. In natural-gas operating mode, emissions of carbon dioxide are cut by over 20 per cent compared to petrol operation.
Operating mode can be switched at the touch of a button
The E 200 NGT can be run on either natural gas or premium unleaded petrol, with the driver being free to decide which of the two drive sources should be deployed. The buttons in the multifunction steering wheel and the central display in the instrument cluster can be used to switch between natural-gas and petrol operation as required.
Ensuring a smooth, jolt-free switch between modes is the task of a special electronic control circuit which orchestrates the changeover for each cylinder individually.
A gauge in the instrument cluster's central display keeps the driver informed of the current level of gas in the reservoirs. Once the supply of gas has been exhausted , the system automatically switches back to petrol operation, so smoothly that the change is imperceptible to the vehicle's occupants. As soon as the reservoirs are refuelled with natural gas, the journey is automatically resumed in the gas operating mode. Carefully honed modifications to the supercharged TWINPULSE engine
The supercharged TWINPULSE engine was modified by the addition of injector nozzles on the underside of the intake manifold. A pressure regulator with sensor and electromagnetic shut-off valve is fitted near the engine to regulate the supply of natural gas and maintain the required system pressure at a constant level.
The reprogrammed engine electronics ensure seamless operation in both drive modes. The E 200 NGT distinguishes itself from comparable models, which often deliver poorer performance in natural-gas mode, by matching the sophisticated four-cylinder power unit's exemplary power and torque characteristics even when running on natural gas. This makes the E 200 NGT the most powerful saloon with a bi-fuel drive unit currently in production.
Comprehensive crash testing
The two fuel sources are stored in a petrol tank with a capacity of 65 litres and four gas reservoirs with a total storage capacity of 18 kilograms respectively. The reservoirs are located in the spare wheel well. A comprehensive programme of crash testing has been carried out to ensure the high standards of safety that Mercedes is renowned for. The leak tightness of the gas reservoirs was subject to particularly rigorous scrutiny, after all the natural gas that is pumped into the reservoirs during refuelling is compressed to a pressure of 200 bar.
When its fuel reservoirs are fully replenished, the total range of the E 200 NGT - based on the NEDC fuel consumption figures - is around 1000 kilometres, of which just under 300 kilometres is covered with the natural-gas drive and the remaining 700 kilometres with conventional petrol power. The saloon may also be equipped with an 80-litre petrol tank as an option, extending the maximum range to nearly 1200 kilometres.
Large boot capacity and the same high payload
With the gas reservoirs fitted, the boot has a load capacity of 400 litres (measured in accordance with the VDA method). In practical terms, this means sufficient stowage space for two jumbo suitcases plus two smaller travel cases. The payload capacity of the saloon with its five-speed automatic transmission is 510 kilograms - virtually the same as in the E 200 KOMPRESSOR.
When seen from the outside, the E 200 NGT with bi-fuel drive looks just the same as any other series-production E-Class saloon. The only difference is that the fuel filler flap is somewhat larger, concealing as it does not only the familiar filler neck for the petrol tank but also a special filler connection for the natural gas, which has been purpose designed to ensure safe and convenient refuelling Costs halved in natural-gas operating mode
Quite apart from the drastic cut in CO2 emissions, running the vehicle on natural gas also holds economic benefits. At the present time, a kilogram of natural gas costs around € 0.72 in Germany, which translates into a cost of around € 0.48 per litre when equated with the energy provided by petrol. This makes natural gas over 50% more cost-effective than premium unleaded petrol. Furthermore, a range of financial incentives - such as tax benefits, public and private support programmes as well as low-interest loans - are on offer in Germany, for example, to assist with the purchase of natural-gas-powered vehicles.
Natural gas represents a feasible alternative to petrol and diesel, both from an ecological and an economical point of view. The fact that it is a primary form of energy allows it to be used in its natural state without any conversion losses. Non-toxic and odourless, natural gas is made up primarily of methane (CH4), meaning that it contains a lower proportion of carbon than any other fossil fuel. Consequently, CO2 emissions are cut by over 20 per cent compared to petrol.
Network of natural-gas filling stations expanding all the time
Expansion of the filling station network in Germany is continuing apace. There are currently more than 550 filling stations in Germany with natural gas pumps, and the number is increasing every week. The total number is set to reach around 1000 as early as 2006, at which point natural gas would be available virtually throughout the entire country. Refuelling with natural gas is extremely straightforward and takes no longer than with traditional fuel types. Furthermore, no losses through evaporation take place and no unpleasant odours are produced during refuelling.
Natural gas is lighter than air. As a result, natural-gas-powered vehicles may be driven into multi-storey car parks and tunnels without any restrictions. Warning signs such as "Entry prohibited for compressed-gas-driven motor vehicles" do not apply to vehicles run on natural gas.
Impeccable levels of comfort and safety, extensive standard specification
The driver and fellow occupants of a Mercedes-Benz E 200 NGT need not compromise on comfort and safety in any way. The standard specification of the NGT saloons is, apart from just a few exceptions, identical to that of the E 200 KOMPRESSOR model.