13.9.2005
GM Technology: Alternative propulsion vehicles
GM presents two new vehicles featuring alternative propulsion technologies at the Frankfurt Motor Show.
The new Zafira 1.6 CNG (Compressed Natural Gas) has its world premier. Furthermore, the GMC Graphyte, a two-mode hybrid SUV concept celebrates its European premiere after its debut at the Detroit Motor Show in January.
Zafira CNG
With the world premiere of the new Zafira 1.6 CNG (Compressed Natural Gas) Opel presents the new version of its best-selling natural gas vehicle in Germany. Today, every third natural gas passenger car in Germany is a Zafira.
The new Zafira CNG again features the unique Flex7 system. Thanks to the clever underfloor arrangement of the four gas tanks around the rear axle. Like its successful predecessor, the Zafira 1.6 CNG features the innovative “monovalentplus” concept, which enables maximum efficiency with natural gas operation. It boasts superb economic efficiency with an output of 71 kW/97 hp. This type of propulsion generates 80 percent less nitrogen oxide than a diesel and around 25 percent lower CO2 emissions than a gasoline engine (diesel: minus 10 percent). In addition, the emissions are free from soot particles, ensuring that the Zafira CNG is not affected by potential driving bans in large cities.
The Zafira CNG is also optimally equipped when it comes to safety: the high-strength steel gas tanks and rust-free stainless steel gas pipes are safely located outside of the impact zone. This was also confirmed by ADAC in a crash test conducted with the first Zafira CNG in spring 2005. Natural gas is much less flammable than gasoline, and in the highly unlikely event of a leak, it dissipates immediately.
A 14-liter gasoline reserve tank ensures continued mobility on routes without a natural gas filling station. Switching between fuel operating modes is via a switch on the center console, or happens automatically when the primary fuel supply is too low. The Zafira CNG has a total operating range of more than 540 kilometers.
GMC Graphyte
The GMC Graphyte concept vehicle is a sport utility vehicle (SUV) with all the capability expected in a four-wheel-drive SUV, but with 25 percent improved fuel economy enabled by GM’s latest two-model full hybrid propulsion system. It was designed and built at the GM Advanced Studio in Coventry, England.
The Graphyte uses a two-mode full hybrid combined with a Vortec 5300 V-8 with Displacement on Demand (DoD) technology. GM’s two-mode full hybrid system has been established as the starting point for the GM-DaimlerChrysler collaboration that is now also joined by BMW. Variants planned include rear-, front- and all-wheel drive versions for cars, SUVs and other vehicles.
The first mode provides fuel-saving capability in low-speed with a combination of full electric propulsion and engine power. The second mode is used primarily at high speeds to optimize fuel economy, while providing full engine power when conditions demand it, such as trailer towing or climbing steep grades. It works synergistically with other technologies such as Displacement on Demand to reduce fuel consumption at highway speeds.
Packaging for the two-mode full hybrid drive system and supporting components in the Graphyte includes a 300-volt NiMH cross-vehicle battery pack located beneath the rear passenger seat and accessory systems under the hood to support the electrically driven HVAC, power steering and power brake systems. The drive system itself, including two compact electric motors and a series of gears that provide an infinite range of drive ratios, is contained within the case of a conventional Hydra-Matic 4L60-E automatic transmission.