Independent, Expert EV Reviews & Advice Since 2006

Smart fortwo cdi vs. Smart fortwo electric drive

The Green Car Guide Smart Car Road Test

The Smart fortwo cdi versus the smart fortwo electric drive

The Smart fortwo cdi vs. the Smart fortwo electric drive

Smart Fortwo

Model/Engine size: Coupe 0.8 cdi Passion 2dr / electric drive
Fuel: Diesel / Electric
Fuel economy combined: 85.6 mpg / 275 mpg equivalent

Green Car Guide rating: 6/10

The Smart fortwo cdi versus the smart fortwo electric drive

The smart fortwo cdi, capable of 85.6 mpg, is the UK’s most economical car, yet the smart fortwo electric drive (ed) doesn’t use any fuel at all; so which is best?

Whatever you think of the smart fortwo, you can’t argue that it’s innovative and it has character. It’s designed for life in the city, with its trump card being its ability to squeeze into super-small parking spaces. With people who love the fortwo, it has certainly built up a bit of a cult following.


The first smart fortwos were petrol-powered, but we now have a diesel version. A small diesel city car doesn’t make as much sense on paper as a petrol version, but it does result in highly impressive fuel economy, and emissions of just 86 g/km CO2.

But never mind petrol or diesel – the smart fortwo, with its pocket-sized city style, looks like it should have been an electric car from the start – and smart claims that this was actually always part of their plan. That idea has now become reality with the appearance of the smart fortwo ed. It’s a zero-tailpipe emission version of the fortwo that has been undergoing trials. So after living with both the diesel and electric models, which makes most sense?


Whichever version you look at, there are obviously common features. Both the diesel and the electric version have just two seats. This will automatically exclude many buyers who will find two seats just too limiting. But most cars are driven around the city with only one occupant, so there’s still a market for a two-seater.

For the driver and passenger there’s actually a good amount of space in the passenger compartment. And the boot, although not huge, is larger than you might expect.

The natural power source for city driving has traditionally been petrol. A petrol engine is light and cheap, and has free-revving characteristics to give the car nippy performance in the city.


Diesel has traditionally been the fuel of choice for larger vehicles and for longer distance driving. Diesel may have lower CO2 emissions than petrol, due to its better economy, but it emits a variety of pollutants that are much worse than those of petrol in terms of local air quality. So diesel is a strange choice for a city car. But it does endow the 3-cylinder common-rail 800cc turbodiesel fortwo with the accolade of the UK’s most economical car. This is obviously something that we should celebrate.

So the smart fortwo cdi is a convenient size for the city, it looks stylish, and if you want ultimate economy, you can’t do much better than this car. But what’s it like to drive?


Firstly, you need to be aware that you can’t adjust the seat height or the steering wheel, so it may be difficult to find a comfortable driving position.

After that, if you’ve spent your life driving ‘normal’ cars, with manual or automatic transmission, then it’s fairly likely that you’ll be shocked when you first drive a smart. It has a semi-automatic gearbox, which basically means that there’s no clutch, and the car changes gears itself. Sounds like an automatic? Well, no – instead of changing gears seamlessly, like a normal automatic, it changes gears with a pause in between. And it’s certainly not an imperceptible, split-second pause.


If you set off in first gear, when the car changes up to second, forward progress dies as the car changes gear, before lurching forwards again when second gear is engaged. This sensation continues as the car progresses through its five gears, which results in a feeling not unlike sea-sickness for the driver, although the sensation diminishes as you climb up the box. Lifting your foot off the accelerator during the gear change helps to make a life a bit smoother.

Changing down the gears is an equally slow process but not as frustrating as going up the box. You would have to be brave to overtake slow moving vehicles on country roads in this car anyway, but the slow gearbox makes such ideas very dangerous.


You can override the semi-automatic change by doing it manually, which is a slight improvement, as at least you can predict when the gear will change and the resultant lurching is going to happen. However this somewhat defeats the object of a semi-automatic gearbox, especially for city driving.

Trying to position the car in exactly the right position in a car wash shows up the flaws of the gearbox – it’s very jerky when having to manoeuvre this delicately.


The brake feel is another area that differs from most ‘normal’ cars, as rather than pushing the brake pedal forwards to stop, you feel as though you are pushing the pedal down into the floor. And the feel of the pedal is not at all confidence-inspiring.

And then there’s the steering, which just feels too heavy for a city car that should be easily manoeuvrable.


So is the diesel fortwo any better on the open road? Surprisingly, yes. We drove the car from Cheshire to Oxford and back, and once you’re up to motorway speeds it’s not as painful as most people might imagine. The ride is better than you would expect in such a short car, and certainly better than the first generation fortwo. The diesel engine is quite capable of propelling the car along, although acceleration up hills is a rather slow process.

You’re very aware that this is a short, narrow, tall car, and so it certainly doesn’t feel planted to the road. The fortwo is also rear-engined and rear-wheel drive, so it would be reasonable to expect some tricky handling, especially on the wet, greasy and muddy country lanes to our offices on cold February mornings. But the stability control system on this latest generation fortwo keeps the back end in check very capably.


If you buy the cdi, you’re likely to be buying it for the promise of its economy, but there’s no fuel economy read-out on the dash, so you can’t even see the rewards of your decision to purchase this car. There’s not even a display of the car’s range (which should be 710 miles). With the ‘Passion’ spec, you do get sat nav and a glass roof, although the buttons on the sat nav/stereo are very small and fiddly, and there are no steering wheel controls for the stereo.

So we’re left with the fortwo being a car that you want to like, but one that also has weaknesses in various areas; the slow, semi-automatic gearbox being the most frustrating issue.


So, step forward the smart ed. Being an electric car, it doesn’t have such a gearbox – it has just a single fixed gear ratio. Once you’ve turned the key, just put the drive lever in the forward position, press the accelerator, and go – there’s a smooth uptake of progress with no gear changes and only a hushed whining noise. So just by eliminating the semi-automatic gearbox the ed already scores ahead of the cdi.

But of course the lack of gearbox isn’t the big idea behind the ed; at a time when there is a relentless focus on CO2 emissions and increasing oil prices, the whole point is that you can drive around with zero tailpipe emissions and no need for fossil fuel.

Instead of filling the car with petrol or diesel, you have to plug the car into an electric socket in your house overnight to recharge it (a full charge takes eight hours). This is actually preferable to having to visit garages and paying huge amounts of money to fill your tank with fuel.


Of course like any electric car the fortwo ed is only zero-emission in terms of its tailpipe emissions (or lack of them). To be truly 100% zero emission, the electricity to recharge the car needs to come from a renewable supply such as a windfarm.

Electric cars are well known for having limited ranges, and the smart is no exception. In fact the fortwo ed, with an official range of just 84 miles (equivalent to five hours of urban driving at an average speed of 18 mph), has a smaller range than cars such as the Nissan LEAF , which can manage around 100 miles.

In a similar way that the cdi has no display showing its remaining driving range, neither does the ed – but this is even more important to have on an electric car than on a diesel. You do get a battery charge gauge, and you’re certainly very conscious of how this drops, like a fuel gauge dropping frighteningly quickly, and how use of the car’s equipment such as the heater fan or air conditioning reduces the range even more quickly.


Then there’s the performance. We’ve driven pretty much every electric car ranging from the G-Wiz through the Nissan LEAF to the Tesla Roadster. Despite Tesla playing a part in the battery development of the16.5 kwh lithium-ion unit, we can quite safely say that the fortwo ed occupies a position at the lower end of the electric car performance spectrum. After a short burst of initial enthusiastic take-up at very low speed, acceleration overall is very slow, especially up hills, and top speed is only 62 mph. This means that the ed is only suitable for use in urban areas.

However although it is best for use in cities it also shares one of the issues with the cdi – the steering cannot be described as light, therefore it’s not ideal for drivers trying to negotiate urban jungles such as London.

In June 2010 smart handed over 100 smart fortwo electric drives to UK consumers for a 12 month trial as part of the Technology Strategy Board-funded Ultra Low Carbon Vehicle Demonstrator Programme. So now that it’s been on trial, can you buy an electric fortwo? No. But smart says that the fortwo electric drive will join the smart model portfolio and will be sold through the smart sales network in 2012.


Summary and Review

Even with its range and performance limitations, you still feel like a pioneer of the brave new world of motoring in the smart fortwo ed because you’re driving on electricity rather than using fossil fuel. We tested the ed in a variety of environments, and our (predictable) conclusion is that it only really makes sense in the city, and in London in particular, where speeds of travel are so slow that you’ll be less likely to notice the limited performance.

If you want an electric car that can also do the occasional run into the countryside then you may have to look at a Nissan LEAF. And the LEAF, with lots of clever technology such as its satnav showing how far you can drive along with locations of charging posts, is actually much smarter than the smart.

This is the first generation fortwo ed. At the Geneva Show, smart showed the ‘forspeed’ concept, and the company acknowledges that performance has been a key item of the feedback about the ed, and improved performance will be a feature of the forspeed.

So the concept of the smart fortwo ed gets the thumbs up; it’s a great size for a city runabout, it’s zero emission, and you can achieve the equivalent of around 275 mpg and save 80% in fuel costs when compared to a petrol-powered smart fortwo (a full battery charge currently costs around £1.70). The ed is on trial and smart is inviting feedback. Our feedback is that it needs better performance and more in-car technology to aid the driver with issues such as range; in its current form it gets a Green-Car-Guide rating of 6 out of 10.

So what about the cdi? It’s great that it has the title of the UK’s most economical car. But a small city car should be more responsive – in terms of its chassis, steering and drivetrain. Gordon Murray is working on this with his T.25 city car, but you can’t buy it yet. In the meantime, the smart fortwo cdi also scores a Green-Car-Guide rating of 6 out of 10; again, gaining marks for providing a sensible-sized and economical mode of transport for the city, but losing marks for the driving experience.

If you’re not ready for an electric smart yet, consider the petrol-powered fortwo – it’s cheaper than the diesel and is more fun to drive around town.

Paul Clarke

A smart fortwo electric drive being charged up

Smart Fortwo Coupe 0.8 cdi Passion 2dr / smart fortwo electric drive

Fuel economy extra urban: 85.6 mpg / N/A
Fuel economy urban: 85.6 mpg / N/A
CO2 emissions: 86 g/km / 0 g/km if recharged using renewable electricity
Green rating: VED band A – first year £0 / VED band A – first year £0
Weight: 770 Kg / 890 Kg
Company car tax liability (2010/11): 13% / 9%
Price: £10,640 (From £9,050 to £16,860) / N/A
Insurance group: 6 / TBC
Power: 54 bhp / 27 bhp continuous power, peak power of 40 bhp
Max speed: 84 mph / 62 mph
0-62 mph: 16.8 seconds / 0-30 mph: 5.8 seconds
DPF: Yes / N/A