On paper they offer negligible emissions and fuel economy into three figures, but what are the Vauxhall Ampera and Toyota Prius Plug-in like to live with in the real world? Paul Barker reports.

Having recently had our electric vehicle charging point installed by British Gas, it seemed appropriate to spend some time finding out what can really be expected from range-extender and plug-in hybrid EVs, as well as pure electric models (see ‘Pure rather than plug-in hybrid’).

Vauxhall’s Ampera and the Toyota Prius Plug-in are among those bridging the gap between petrol or diesel and the EV technology that currently has too many concerns over vehicle range to be used by most fleets. BusinessCar spent a few weeks in each model to see how they work in the real world, and how actual economy compared with the official 235.4mpg for the Ampera and 134.5mpg for the Prius Plug-in. Those figures are almost irrelevant because the technology is so dependent on what percentage of time a user drives on electric power, so we set out to see what can be achieved in regular usage across three very different types of journey.

My commute is 35 miles of urban, A-road and motorway driving, while BusinessCar’s news and features editor Jack Carfrae lives 70 mainly dual-carriageway and motorway miles away from the office. Meanwhile, James Dallas, deputy editor of sister title What Van?, took the cars on his 12-mile commute across south London. I’m the only one with the set-up to charge from home (a standard three-pin plug on its own circuit) so Jack’s journey illustrates what mpg can be expected with minimal electric running, while James’s tests how the cars cope with low-mileage urban trips.

We’re aware this isn’t a highly scientific experiment, but hopefully gives some insight into the sort of results different usage patterns return on this fledgling technology.

 

Ampera

Although Vauxhall quotes an electric range of 25-50 miles for the Ampera depending on how it’s driven, we averaged 29.0 miles overall before the battery ran out and the car switched seamlessly to the 1.4-litre petrol engine. Jack’s longer and generally steady higher-speed runs averaged 34.7 miles, while the urban runs averaged just 25.4. My mixed commute returned 29.7 miles.

It was noteworthy just how transparent the Ampera makes things, offering a huge central screen to show exactly which power source the car has been running on and the resultant fuel economy since it was last plugged in.

Also worth noting, for both home and work charging, is that the Ampera’s socket is at the front of the car, which means you have to go nose-in to a space and reverse out, which, given the car’s below-par visibility, make this a potentially perilous manoeuvre, especially at my house, where I have to reverse off a driveway that drops sharply from the kerb, across the pavement and into the road between parked cars while not able to see what’s speeding past particularly well. The textbook parking approach is to reverse in and drive out, but that’s not possible if you need to charge the car.

Once the battery runs out, the fuel economy figure plunges rapidly from a default 250-plus mpg readout, and ranged from readings of 147-195mpg on my 35-mile run. I also used the car for a 90-mile trip with no recharging opportunity and returned 55.6mpg, while a 42-mile series of short hops returned 112mpg. A 77-mile route from home and into London before heading back to the office showed 68.1mpg. These figures were all taken in the cold snap a few weeks ago, and we’d have expected slightly better in warmer conditions.

In town, it was surprising how quickly the battery ran out, given the stop-start nature of south London traffic and the effect we expected that to have or energy recuperation. The battery lasted 20, 21 and 25 miles on the three commutes undertaken across the south circular, which was less than we were expecting, and contrasted surprisingly with the minimum of 30.3 miles achieved by Jack on his longer runs that admittedly also took in the Dartford Crossing and its notorious toll booths. Those longer, steady-speed runs, where the car was doing around 100 miles on petrol power and around 35 on battery, still provided some rather impressive fuel figures, with the computer settling down to an average of more than 60mpg. The decline in mpg seems to slow down after that, so the expectation would be that even longer runs would still record in excess of 50mpg, even with minimal electric input.

 

Toyota Prius Plug-in

The Prius is a different kind of plug-in to the Ampera, in that rather than running on electric power then switching to petrol when the battery is drained, it will try and use the rechargeable battery as an extension of the existing hybrid system, and optimise between petrol engine and electric motor. That led to frustrating journeys, especially short hops, where despite being set in electric mode and having plenty of battery charge, the car wouldn’t run just on the battery. For example, a four-mile round trip to our nearest railway station should have comfortably been completed on battery alone, but the engine kicked in a few times when it wasn’t needed.

My 35-mile trips ranged from 67-81mpg, the top figure – two miles per gallon better than the next – being achieved without using the air-conditioning. On that journey I managed 9.4 miles on the smaller electric motor, compared with Toyota’s claimed 15.5-mile capacity. It’s not supposed to be as efficient as the Ampera – the technologies are different – but exceeding a real-world 70mpg on most trips was impressive. For comparison, a BMW 320d Efficient Dynamics would have been around 10mpg off that figure from our experience.

But the frustration continued with the batteries for all drivers. James managed a 48-mile journey with 2.3 miles of electric range still intact, and another 26-mile round trip where it still had 0.3 miles, while I also had a 35.7-mile run into work where there was 0.3 miles of charge left when I arrived. Jack’s longer commutes averaged 58mpg, showing the kind of numbers that can be expected, putting it in the same ball park as the Ampera on big trips when you’re quickly exceeding the electric range.

The overriding feeling with the Prius, though, was that it’s not quite as complete a range-extender as the Ampera, which is maybe half a stage more technically advanced. The Toyota is cheaper, costing £33,245 compared with the Ampera’s £34,995-£38,995 before the £5000 Government grant towards the purchase price. The Prius just feels like an adaption of a current model, which is what it is, whereas the Ampera is a bespoke range-extender. Little details such as the Ampera’s readout showing exactly where the energy is coming from, with a pie chart to make the point, aren’t replicated with the Prius.

Both proved to be more efficient than a traditional diesel model over short and medium-length journeys, and can match diesels on runs of up to around 150 miles, so the key, as is increasingly the case, is usage.

Spend all day ploughing M- and A-roads, then a diesel is perfect and plug-in cars aren’t suitable. But especially for drivers that commute a small or reasonable distance and can charge at home and work, these models start to make a lot of sense, especially with the continued, if reduced, BIK advantage. If you can foot the purchase price, and they fit your lifestyle, then they are the beginnings of the future.

 

Pure, rather than plug-in hybrid

In the wake of British Gas fitting our new electric vehicle charging point at the beginning of this year, BusinessCar also wanted to see just how practical, or not, a pure-electric vehicle actually is.

We took delivery of a Nissan Leaf EV and a petrol-powered Nissan Juke to see which would cover the most miles over the course of a fortnight; the Juke being called into action on the days the Leaf didn’t have the range to complete my journey.

The bad news is that the Juke took it by a much wider margin than anticipated – 1101.3 miles versus 227.4 – but there were some particular circumstances that didn’t help the electric Nissan.

The way my diary worked out meant there were a couple of times where I had to go somewhere on the way to work, such as a meeting that added another 35 miles to my journey to the office and tipped it just over what was worth risking from a range point of view. That attitude towards range anxiety has in various EV trials proved to diminish with time. Trips from Sussex to Daventry and Milton Keynes on the other hand, wouldn’t have been possible without a lengthy pause for recharging no matter what the attitude to range anxiety. If I had just been in the office, then the majority of the mileage would have been in the Leaf, which generally speaking was comfortable with a 35-mile trip between charges. The one exception was the time I took the longer but mainly motorway route to work and arrived with nine miles of battery life left after a 40-mile run, despite the Leaf claiming more than 100 miles of range. Higher speeds sap the battery, and only a lengthy stretch of 50mph roadworks saved me, although I could have helped the situation by easing off from the motorway limit the rest of the time.

My own lack of EV experience/stupidity also cost the Leaf running time. Attending another carmaker’s event at the Stratford shopping centre in east London, I was too late to charge the car when I got back to the office in order to get home, so switched to the Juke. But with a bit more research, rather than spotting them on the way out, I would have known there were charging points at the centre, which would have boosted the car enough to add another 70 miles to its total at the expense of the Juke.

Another example of range paranoia was a trip to see my parents, where a combination of recharging time worries and the distance – 40 miles of mainly dual carriageway – meant I chickened out and took the Juke when, with reduced speed and a recharge over lunch, I would probably have been fine.

It makes the point that pure-electric vehicles are very different to the convenience of internal combustion engines. They won’t suit everyone, but experience is the only way to find out how they can work. After my fortnight with both cars I feel much wiser about the concept of EVs and I’m certainly now better equipped to judge their real-world utilisation as a result.