Our Holden Volt
I took an interest in the Volt when they first came out in 2011 and finally did something about it when, in a moment of madness, I purchased a second hand Volt in April this year. They are hard to find as only few were sold in Australia and the people who bought them seemed to like them, so not many turn up in the market. I imported this car from South Australia and had it transported to Canberra. It is a hybrid electric car but it functions differently from all other hybrids I know of. The Volt is always driven by its 110KW electric motor from a 16.5 kWh battery. When new, the Volt had an electric range of over 100km, but my Volt is 8 years old and has lost about 30 km. In hybrid mode it has a range of 600km.
When in hybrid mode a 1.4L petrol engine drives a generator that provides power to the electric drive motor and maintains the charge in the battery. When accelerating or going up hills the electric drive motor takes power from both the generator and the battery and then, when the load eases, the petrol motor charges the battery and maintains the battery charge at the hold point. The Volt never fully discharges the battery but automatically switches to hybrid mode when the battery reaches 20% capacity. Regenerative braking also charges the battery which, when driving down the Clyde, puts around over 10km into the battery.
I charge the battery at home which I usually do when solar output is high. This allows me to keep nearly all of my local driving electric and costs a measly 2 cents per kilometre foregoing my feed in tariff of 9.5c/kwh. On a recent trip to the NSW far north coast driving in hybrid mode at 110km/hour on the motorway, fuel consumption was 6L/100km.
Hybrid mode saves fuel as if it allows the petrol engine to operate at high efficiency steps producing electricity for propulsion and battery charging independent of the vehicle’s speed. Additional energy for accelerating or climbing hills comes from the battery allowing the petrol engine to stay in its sweet spot.
The Japanese hybrid cars drive with the petrol motor directly connected to the transmission and use the electric motor to boost acceleration and climb hills. The latest Toyota Corolla hybrid for instance, has a 90kw petrol motor, a 50kw electric motor and a 1.3 kwh NIMH battery. They can drive sedately in electric mode for only around 5km and the battery can not be plug charged. The combination of petrol and electric achieves very impressive fuel consumption with claimed figures of 4.5L/100km.
The Volt is a pleasure to drive with quiet, smooth, silent power on tap. I am looking forward to many years of economical low emissions driving when, by then, pure electric long range vehicles will be the norm.
Rob Shorrock
