In January 2012, Opel will introduce a new natural gas ecoFLEX version of the Zafira Tourer—itself recently introduced at the 64th Frankfurt Motor Show in September. The new natural gas Zafira Tourer will offer a range of up to 530 km (329 miles). Like the previous model, the Zafira Tourer features Opel’s monovalentPlus system and has a 14-liter gasoline reserve, giving it an extra 150 km (93 miles) of range.
The Zafira Tourer 1.6 CNG (Compressed Natural Gas) Turbo ecoFLEX delivers 110 kW (150 hp) with 210 N·m (155 lb-ft) of torque and reaches a top speed of 200 km/h (124 mph). The vehicle uses 4.7 kilograms (7.2 m3) of natural gas per 100 kilometers in the combined cycle which is at least 6% better than the predecessor Zafira CNG model. CO2 emissions were reduced to 129 g/km (predecessor: 139 g/km).
|the new natural gas ecoFLEX version of the Zafira Tourer. Click to enlarge.|
The 1.6 liter engine can run on biogas or a mixture of natural gas and biogas. In the case of 100% biogas propulsion, the carbon foot print is almost zero.
The extended CNG range of the seven-seat vehicle represents an improvement of around 25% on its predecessor. These enhancements have been mainly achieved with a new light weight gas tank system providing an increased CNG capacity of now 25 kg (predecessor: 21 kg) and an optimization of the drivetrain.
Opel engineers increased the volume of the gas tanks to 25 kg from the previous 21 kg. This helped boost the operative range in the CNG mode by around 25% to 530 km. Rather than using conventional steel gas cylinders, the engineers opted for advanced composite material including carbon fiber. The use of this lightweight material resulted in a weight saving of 85 kilograms.
The use of electronic pressure regulators rather than mechanical ones, as in the Zafira CNG predecessor model, also helped boost the range. The electronic regulators ensure that when the gas cylinders are almost empty, even small remaining reserves can be efficiently exploited.
On the engine side, the optimization includes several measures: as natural gas has an anti-knock resistance of up to 130 octane, compression can be increased, yielding greater efficiency. The increase in the compression ratio is also supported by a piston specially designed for use with natural gas. The cylinder-selective sequential injection, with an injection block and four injectors for natural gas and gasoline, also permits precision control of the injection timing and quantity. This reduces harmful emissions, leading in turn to cleaner exhaust gases.
Since launching its first CNG vehicle in 2001, Opel has sold more than 70,000 CNG-powered vehicles throughout Europe, including the Zafira, the Astra Caravan and the Combo. More than two-thirds of total CNG sales are for the Zafira. This makes the Zafira the undisputed bestseller and flagship of Opel’s CNG offering. Opel has consistently been in the top three manufacturers in terms of total European sales in the CNG segment.
While the Zafira 1.6 Turbo CNG version is still available, the new Zafira Tourer 1.6 CNG Turbo ecoFLEX takes the Opel CNG offer up-market. Prices for the Zafira Tourer CNG version, which can already be ordered, start at €27,950 (US$37,297) (recommended retail price in Germany, including VAT). CNG vehicles like the new Zafira Tourer also offer significantly lower running costs than their gasoline counterparts. For example, in Germany CNG is 50% less expensive than gasoline.