Phoenix has such a broad spectrum of low emission vehicles, with the impressive Honda Civic Hybrid, Mitsubishi i, Mitsubishi Outlander and the BMW 1 Series leading the way.

Honda is still on track to preview its new small global hybrid model in autumn 2008, either at the Paris Motor Show or the Los Angeles Auto Show, before it goes on sale in 2009. The new model is a dedicated hybrid hatchback rather than a hybrid version of one of Honda's existing models, and it'll be cheaper than the Civic Hybrid.

Honda plans to start off with production of 200,000 units per year of this new-dedicated hybrid. But the car won't come with lithium-ion batteries, currently seen as the way forward for hybrids, according to Honda president Takeo Fukui. "When we think about safety and cost, the introduction of lithium ion batteries will be years ahead," Fukui said.

The fact Honda has already applied lithium ion battery technology to its new FCX Clarity fuel cell car suggests that it's simply too expensive to the brand's new global hybrid. Although the new model won't be a sports car, Honda unveiled a small petrol-electric coupe concept at the Geneva show in March, hinting at its plans for a stand-alone hybrid.

Mazda RX-8 Renesis

The Mazda RX-8 Renesis hybrid is the world's first rotary hydrogen-gasoline hybrid car.

The Renesis Hydrogen Rotary Engine incorporates an electronically controlled hydrogen injector system coupled with a pressurized hydrogen tank. The dual-purpose engine can also run as well on gasoline as it can on hydrogen.

The Mazda RX-8 Renesis hybrid car also employs other environmentally friendly features that are not immediately obvious. For instance, the RX-8 uses a water based paint, applied wet three times, which reduces the emission of organic solvents, speeds drying time and reduces CO2 gases. The RX-8 also uses plant based plastic parts on the interior that are not derived from petroleum unlike other plastics.

According to Mazda, "The RENESIS Hydrogen Rotary Engine incorporates an electronically controlled hydrogen injector system (the hydrogen is injected in a gaseous state). The system draws air from the side port during the induction cycle and uses dual hydrogen injectors in each of the engine's twin rotor housings to directly inject hydrogen into the intake chambers. By virtue of its construction, with separate chambers for induction and combustion, the rotary engine is ideally suited to burn hydrogen without inviting the backfiring that can occur when hydrogen is burned in a traditional piston engine. The separate induction chamber also provides a safer temperature for fitting the dual hydrogen injectors with their rubber seals, which are susceptible to the high temperatures encountered in a conventional reciprocating engine."

Even More Environmentally and Efficiency Friendly Systems from Mazda

Other environmentally and efficiency friendly systems that Mazda is working on for future generations, include, regenerative braking, idle-stop systems and electric acceleration assistance systems.

An electric motor assist turbocharger is being developed to enhance the efficiency of hydrogen combustion and regeneration of energy from the car's exhaust. Mazda also plans to merge the hydrogen-gasoline hybrid system with an electric motor counterpart, or tribrid technology, in order to create even greater efficiency and cleaner running systems than ever before. This tribrid technology will feature an electric motor, inverter and 144v battery and H2ICE engine.

Tribrid technology will likely replace hybrid technology for other vehicles as well in the transition to all-hydrogen technology when the hydrogen economy starts to take hold.

Mazda Senku

The Mazda Senku is "a four seater rotary sports car for adults" and is one of Mazda's newest hybrid car offerings. The Mazda Senku made its world premier at the Tokyo Motor Show at the Makuhari Messe, Chiba prefecture in October 2005. Mazda unleashed a variety of cars and technological advances at the 2005 Tokyo Motor Show, but it would be fair to say that most eyes were locked on the Senku.

The Mazda Senku is a concept car that will not only be reliable but also exciting. The Senku has the first ever rotary hybrid engine power train based on a next generation 13B-DI direct injection gasoline rotary engine with a hybrid unit. Mazda has designed the hybrid power train itself, using a new direct injection two-rotor engine that is combined with a battery, motor and generator.

The battery is located between the engine and the firewall, which helps create an equal distribution of weight and maintain a lower centre of gravity. As with some other hybrid systems, the Senku includes an "idling-stop system" that helps boost the fuel economy of the vehicle and lower overall emissions.

The Mazda Senku has a tremendously sleek design, complete with long sliding electric doors. The car is 15.3 feet long, 73 inches wide, and 55 inches tall which makes it bigger than the Mazda RX-8. It also has a 122-inch wheelbase. The Senku is built on a new style of multi-frame technology that saves weight and makes the car safer in impact situations. The multi-frame technology essentially supports the engine and front suspension and pillars are placed inside the backs of the car doors to maintain rigidity despite the sliding door openings.

The Senku comes with seven-speed manual transmission and a twin-plate clutch, double wishbone suspension, and huge Yokohama Prototype 005 tires. It also includes a power-operated hatch that lifts the glass roof to reveal solar panels that assist in charging of the battery. The sliding doors are also electric.

Many that have viewed the Mazda Senku are quick to comment on the sleek design and the fact that the car appears to be "floating" because of the wheelbase, huge tires, and literally no overhang. The shape of the vehicle is smooth and sleek, with no clattering ornamentation to distract the consumer. Others comment on the large amount of personal space and the comfort of the leather seats. One could make the argument that the Senku was one of the roomiest and "zoom-zoomiest" cars at the show. Truly a luxury hybrid hydrogen machine for a new generation of "mature" drivers, the Mazda Senku is a true ‘head turner’.