This is an excerpt from EERE Network News, a weekly electronic newsletter.
Three GM SUVs to Feature "Displacement on Demand" in 2005
While many automakers are investigating hybrid-electric technologies as a fuel-saving measure, a number of other technologies are being gradually introduced into the automotive market that can also contribute significantly to fuel economy. General Motors Corporation (GM), for instance, will make its new "Displacement on Demand" technology a standard feature on its Vortec 5300 V-8 engine, which is an option on the GMC Envoy XL, Envoy XUV, and Chevrolet TrailBlazer EXT. The new feature will be available in Model Year 2005 and will achieve an 8 percent increase in overall fuel economy by using only 4 cylinders when the engine is operating under a light load. The control system accomplishes this feat by closing the intake and exhaust valves for the other four cylinders. GM expects to introduce the system on V-6 engines in some mid-size cars in 2006, and hopes to sell more than two million vehicles with the feature by 2008. See the GM press release.
Aluminum bodies are another energy-saving innovation, and the new 2004 Jaguar XJ features an aluminum body that cuts 200 pounds off of its weight. The aluminum parts are joined by self-pierce rivets and epoxy adhesive, a process adapted from the aerospace industry. See the Ford Motor Company press release.
Aluminum bodies are nothing new for Audi; in the past decade, the company has produced 250,000 of its A2 and A8 models with aluminum bodies. According to Audi, the aluminum bodies "achieve a noticeable reduction in fuel consumption and...improve comfort, performance and safety at the same time." See the Audi press release.
Automakers are also investigating "drive-by-wire" technologies for steering, throttle, shifting, and braking, replacing heavy mechanical linkages with lighter electronic controls. The 2004 Toyota Prius, for instance, will use such "by-wire" technologies to control the car's throttle and shifting. See the Prius press release.