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Chevrolet Volt

Very briefly outlined the Chevrolet Volt is a serial/parallel hybrid in which two different strong electric motors are mechanically connected to a small car internal combustion engine via a planetary gear. From the Toyota principle two additional clutches it distinguish within this mechanical branching. The sake of completeness must be noted that the smaller electric motor also can operate as a generator.

The two clutches have the sense that the control of the complete system can always select the most favorable combination, with more degrees of freedom than the Toyota. Favorable usually means the best possible degree of efficiency, on demand, for example, by driving in the mountains or corresponding driver's request however, also the maximum power.

Actually a normal ride starts with charged battery with the big electric motor. In between, can also without special request the combustion engine be started to flush the system and to consume some gasoline. The possibly month long storage of always the same fuel in an albeit completely closed tank system is not without problems.

USA: In general, higher consumption due to lower octane number.

At a somewhat higher speed, the controller sees a chance by switching on the second motor to relieve the first so that the efficiency is improved. Of course, this also happens at higher performance requirements, can even lead to switching on the internal combustion engine. Incidentally, the runs with the highest, at all gasoline stations in the U.S. available octane number of (only) 91.

The lithium-ion battery is housed in the wide tunnel and rear transversely under the seats. Its capacity is already risen from 16 to 16.5 kWh in 2013. But for reasons of durability are usable only 10.3 respectively 10.8 kWh. Thus, it supposed to be tested indeed on 5000 charge/discharge cycles. That would be, purely theoretical, at each time fully exploited 80 km range 400,000 km.

In practice will much more often much less charged and also be driven faster, which the range let significantly shrink to up to 40 km. In the Chevrolet Volt is 'only' a single-zone air conditioning and a tendency to heat the seats stronger instead of the interior. The pre-heating makes sense during charging, however, the lasts with usual local 120 V and 15 amperes approx. 12 hours. The grip to the pocket calculator discloses during charging a loss of 30 to 40 percent. By the way, at 240 V installation, it goes much faster with four hours.

So far, you might think, to have to deal with a serial hybrid. In reality, however, the combustion engine can also drive the vehicle and that it does, for example if the high-voltage battery is at the end. Here, however, care is taken to continue favorable efficiency. So if it's more favorable to keep the engine at a fuel-efficient engine speed, torque can also be generated by the electric motor in addition, while the smaller electric motor operates as a generator.

The consumption values are well below 7 liters per 100 km in Range Extender mode. It must always take into account the relatively high weight and the not particularly favorable air drag. USA is a land of plenty for electric cars. Look at only the original price to the dealer costs can still be added, but will be deducted also from 0 to 7500 dollars depending on the federal state.

There is a kind of City mode, there you consciously use the combustion engine in the countryside to be able to cross the city with electrical energy only. One may with electric cars on highways sitting alone in the car use the lane, which is usually reserved for cars with more than one person (see pictures). In San Francisco, parking is free everywhere and the current also. Anyway, the costs usually only one third compared with the in Germany. 01/14

Identical with the Opel Ampera