Oct. 6, 2003

A GUIDE TO HYBRID CARS AND OTHER FUEL-EFFICIENT TECHNOLOGY HYBRIDS

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Specific Models and photos.

The most fuel-efficient vehicles on the road today are hybrid-electric cars. Honda and Toyota have led the auto industry in putting advanced hybrid vehicles on the road, and are currently the only automakers with commercially available hybrids. A hybrid combines an electric motor with a conventional, but cleaner, gasoline-powered engine. The gasoline engine generates electricity for the electric motor, and shuts off during regular driving conditions. The energy typically lost to braking is also preserved to recharge the battery. This means that a hybrid never has to be plugged in - you just fill it up at the gas station like any other car.

Hybrid engines can improve the fuel economy of any vehicle. At the 2003 Detroit Auto Show, Toyota, General Motors, and Ford all announced that they would produce hybrid-electric SUVs within the next two years. At 35 to 40-mpg, these vehicles demonstrate that automakers can build SUVs and pickup trucks that get significantly better fuel economy using existing technology.

Switching to a hybrid engine goes a long way toward cutting our oil consumption and protecting the environment - not to mention reaping big savings at the gas pump. Over its lifetime, a 50 mile per gallon hybrid Toyota Prius will use half as much gas, and release half as much global warming pollution, as a 23-mpg Ford Taurus.

OTHER FUEL-SAVING TECHNOLOGIES – THE FREEDOM OPTION PACKAGE
There are other technologies, short of hybrid engines, that can make substantial improvements in fuel economy. These fuel-saving components are on the road today in some vehicles, but should be in more. The Sierra Club has grouped many of these technologies together to create the Freedom Option Package - a set of cost-effective building blocks to boosting fuel economy. It’s past time for U.S. automakers to do their part and incorporate these technologies into their vehicles.

Here are examples of key fuel-saving technologies:

• The Continuously Variable Automatic Transmission (CVT) replaces the standard gear ratios with a continuous "belt", maximizing the engine's performance and efficiency.
• The Integrated Starter Generator (ISG) allows the gas engine to shut down when the vehicle is stopped and idling. Cars burn as much as 15% of their gas while stopped in traffic
• The Variable Valve Control Engine (VVCE) regulates the engine's mix of fuel and air more precisely.
  ·  Cylinder deactivation, also called
• displacement-on-demand, further enhances fuel savings by automatically closing intake and exhaust valves and sealing off unneeded cylinder when less power is required.
• Improved Aerodynamics can lead to increased fuel economy by reducing drag. Researchers believe better design could reduce light truck drag by about 10 percent and car drag by about 10 to 25 percent.
• Greater use of High-Strength, lightweight materials such as steel, aluminum, and plastics can all play a role in helping vehicles shed weight while enhancing safety.
• Using Low Rolling-Resistance Tires improves fuel economy by easing the movement of the vehicle.

Toyota Prius (45/52 mpg). The Prius runs on Toyota’s Hybrid System (THS) which combines an efficient VVT-i gas engine with an electric motor. In addition, the Prius employs an integrated starter generator, continuously variable transmission and regenerative braking systems.

Honda Civic hybrid (47/48 mpg). The Civic hybrid also uses the IMA hybrid system as well as Honda’s V-TEC engine, along with an integrated starter generator and other fuel-saving technologies.

UPCOMING HYBRIDS
Toyota Prius 2004 (58 mpg). Toyota has redesigned the Prius for the 2004 model year. The new Prius will be larger, more powerful and get better fuel economy than the current Prius design. The company has developed a new hybrid system, the Hybrid Synergy drive, which has a 50% more powerful electric motor than the THS. The acceleration will be comparable to a Camry 4 cylinder. In addition, the new Prius will have the interior space of a Corolla, classifying it as a mid-size vehicle. The new Prius, like the old, will have an ISG, CVT, VVT, and regenerative braking.

Ford Escape (c. 40mpg). Ford has announced plans to launch a hybrid version of its Escape SUV in the 2004 model year. This vehicle will employ both an in-line four cylinder engine (I4) and an electric motor that will have the performance of a V-6. In addition the Escape will have an integrated starter generator and regenerative braking.

Lexus 330 (35-40 mpg) - Toyota unveiled its Lexus RX-330 hybrid SUV at this year’s Detroit Auto Show. It will be released either at the end of the 2004 model year or early 2005. The RX-330 hybrid employs both a V-6 engine and two electric motors to deliver the power of a V-8 engine. The front and rear electric motors create an all wheel drive vehicle, without the bulk and weight of a conventional 4WD system.

Saturn VUE (35-40 mpg). General Motors has announced that it will introduce a hybrid Saturn VUE SUV for the 2005 model year. The VUE will use a hybrid system that employs two electric motors along with a gas engine, possibly GM’s 4 cylinder Ecotec engine. In addition, the VUE will use GM's continuously variable transmission, and cylinder deactivation.

OTHER MODELS CURRENTLY ON THE ROAD THAT USE SOME FUEL-EFFICIENT TECHNOLOGY
Saturn VUE (22-28 mpg). GM offers a continuously variable transmission (CVT) as an option on their Saturn VUE. The addition of the CVT increases the fuel economy of the VUE by about 10%, in addition to providing additional power to the engine.
GMC Sierra and Chevy Silverado (17mpg). GM plans to create so-called ‘hybrid’ versions of these two pickup trucks. In reality, they are not true hybrid systems, since the electric motor does not provide a significant source of the vehicle’s propulsion. This is reflected in the vehicle's low fuel economy - it's only a 10-15% improvement on the non-hybrid models. The new designs will also include a 42-volt integrated starter and cylinder deactivation. The company plans to market these vehicles to contractors, since the on-board electric motor can serve as a generator at work sites.

Audi A6 and A4 (23-25 mpg). Both the Audi A6 and A4 offer the option of Audi’s Multitronic CVT transmission. Unfortunately, the power gains are put largely towards speed and acceleration rather than fuel economy.

Honda’s V-TEC engine. Found in most Honda and Acura vehicles, this is Honda’s primary engine that employs variable-valve control to improve engine performance and fuel economy.

Toyota’s VVT-i engine. Toyota’s variable valve control engine is found in certain Toyota and Lexus models.

BMW’s Double Vanos VVT system. BMW offers its Double Vanos system in select models of its 3 series engine. But the power gains are tuned towards speed and torque as opposed to fuel economy.

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