Honda Civic e:HEV in the test: series hybrid promises low consumption values

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Honda's full hybrid technology was first launched in Europe in 2019 with the CR-V under the designation i:MMD (Intelligent Multi Mode Drive). The mode of operation even then: The combustion engine drives a generator, which produces electricity that is fed into the battery and/or passed directly to the electric drive motor - so far, then, a serial hybrid. In certain driving situations, however, a direct drive from the combustion engine to the wheels can also be created by closing a clutch in the simply designed transmission. The serial hybrid then becomes a P1/P3 parallel hybrid.

For the newer models such as Jazz and Civic, Honda now uses the designation e:HEV, i.e. "electric : hybrid electric vehicle", in other words. Honda also likes to talk about a self-charging hybrid. That sounds a bit like a perpetual motion machine, but basically it just means that the electric drive motor plays the main role in Honda's hybrid drive and the combustion engine primarily generates electricity.

What Honda's hybrid drive delivers in practice

The operating strategy of the Honda drive system always selects the mode that offers the best efficiency during driving. The choices are all-electric, series or parallel. A novelty from the outset was what Honda developers call alternating operation: One operating state is that the combustion engine not only provides propulsion, but at the same time runs slightly against the generator to produce electricity. In this way, the gasoline engine runs at its optimum operating point. The collected electricity then makes it possible to drive a certain distance purely electrically, which is the second of the two alternating states.

This may sound a bit strange at first, but this "alternating" is an essential element in achieving good efficiency despite the serial operation that was frowned upon in the past. It is a permanent game with efficiencies. Parallel operation, on the other hand, only comes into play when direct drive is more efficient, typically at constant speed on a country road, for example.

Consumption values in comparison

In everyday use, I drove the Honda Jazz on just over four  liters of gasoline, and the Honda HR-V on about 4.6  liters. My colleague Christoph drove the new Civic with a good five liters. However, it only manages that under favorable conditions: At my place, the Civic test car landed at the beginning of December 2022, and the first test drive took place at -7 °C. It likes that less. Firstly, the combustion engine has to run more to avoid cooling down too much per se, and secondly, to be able to provide enough heat for the interior and battery. This is because the interior air conditioning is also used for battery temperature control. Experience with the Jazz and Civic shows that you can expect a heating supplement of a good ten percent when it gets really cold. On my first drive, I got a consumption of a good six liters; on a longer stage, it was a bit more than five.

Serial hybrid: Often in the optimum engine map range

Serial operation can also make sense from today's perspective. Unlike drives with stepped transmissions, Honda can very often operate the combustion engine in an optimum map range, i.e. ideally balance the proportion for propulsion and generator operation. Another effect is the opposing characteristics of the electric motor (here a permanent magnet synchronous machine - PSM) and the internal combustion engine: The former is at its most efficient at low loads and speeds, while the opposite is true of the internal combustion engine - especially in the case of a gasoline engine that operates in the Atkinson cycle, as Honda uses in all its hybrids. In the Atkinson cycle, the intake valve is closed later than normal. Efficiency increases, while power output decreases compared to the conventional closing angle of the intake valve.

Honda has reworked this point: While the maps of Atkinson engines are usually comparatively pointed, the thermal efficiency of the new two-liter engine is said to be higher than before and the range of favorable consumption in the map over load and speed has nevertheless been expanded. For the new engine - unlike its predecessor now also with direct injection - Honda states a maximum efficiency of 41 percent. As for the term "predecessor", it should be noted that this engine was used in the CR-V, while the Civic is the first to feature this hybrid drive.

Civic e:HEV: sporty and comfortable

More surprisingly, I found that the new e:HEV generation has taken an amazing step forward in terms of comfort. This is particularly clear in comparison to the Jazz and HR-V, which with their 1.5-liter engines are quite noisy under high load, caused by second-order inertia forces, among other things. The new 2.0 engine in the Civic, on the other hand, runs almost vibration-free in all operating ranges, despite the often high engine speeds. It is not loud, but has a slightly growly, quite pleasant note. Transitions between the various hybrid operating modes, including switching the engine on and off, are practically imperceptible.

In terms of power delivery, the Civic is very confident. When accelerating, the 135 kW and 315 Nm are straightforward and effortless. Caution: danger of fun. By the way, the fact that the combustion engine "only" produces 105 kW doesn't matter, because the acceleration capacity is normally defined by the electric drive motor alone. Honda has designed the operating strategy in such a way that the demand for typical acceleration processes can practically always be fed from the battery with its just over 1 kWh. You have to drive up a longer incline at full speed to have to make do with 105 kW minus the conversion losses. But who drives up an Alpine pass at full throttle?

Eco preferred

Basically, the Civic has outgrown its class, a Gran Turismo that allows comfortable and selectively sporty cruising. Of the three modes "Eco", "Standard" and "Sport", the first has the merit of accommodating a gliding driving style with a less "sharply" translated accelerator pedal. The Sport mode, on the other hand, very spontaneously designed, with harder steering, offers the fun extra of an artificially but not exaggeratedly amplified engine sound. In addition, you can create your own individual mode, for example with soft throttle response and tighter steering, and so on. The steering wheel paddles are not used here for shifting, but for manually selecting more or less strong recuperation. I quickly didn't want to do without them, because you can harvest charging current in a controlled manner, especially when going downhill.

Apart from the two-liter engine of the new generation, Honda has revised a few other things: The power electronics are more highly integrated, and the battery now has a specifically higher energy density. In addition, according to Honda, increased their usable range, was able to reduce the reserve, which is necessary to avoid aging. All these, by the way, are features that it shares with the new CR-V, which has already been unveiled in the United States. Its official specifications for the European version are still pending.

New models Honda CR-V and ZR-V

Given the Civic's powertrain performance, it can be assumed that the new CR-V's performance and comfort will also gain significantly. The engine basis is the same, but more powerful e-motors are installed, at least in North America. The electric drive motor here produces 150 kW. Since this results in slightly more overall length, Honda has also taken this opportunity to change their arrangement: While the e-motors have been arranged one behind the other in all models so far, they sit side by side in the CR-V. This also requires a new transmission and brings the next innovation.