Find out the pros and cons of Alternatively Fuelled Vehicles.

With the way motoring tax is moving it is clear that governments around the world are trying to push us out of petrol and diesel cars and into hybrids, plug-in hybrids, electric cars and other AFVs – Alternatively Fuelled Vehicles.

But what does it all mean, do they work for you and if so, which is the most suitable.

Here we cast our eyes over the various types on sale and their pros and cons and give you a driver’s eye view of what it’s like to drive one of the market favourites.

But first let’s clear up some terminology.


Hybrids.

Cars which have both a normal internal combustion (i/c) engine and an electric motor to power them. Computer controlled, they can run on either one or the other depending on the type of driving you are doing or even both when you need maximum torque for accelerating. As the car brakes, energy which would normally be lost as heat through the brake discs and pads is effectively captured and pumped back into the battery to recharge it.

 

 

Pros: By far the most popular of all AFVs on sale at the moment. They rely mainly on the conventional engine but the battery can power the electric motor for short town journeys or to add its punch when you need maximum torque, such as when accelerating or going up a hill. Unlike a pure electric car there is no fear of running out of power. Also, with bigger towns and cities looking to tax cars more for entry it stands to reason this class of car will be looked on more kindly than those with no electric power.

As a rule of thumb, heavier cars like SUVs should be ideally suited to hybrid engines because (a) the extra power of the electric motor is great as they accelerate and (b) they are thirsty cars so anything which helps their consumption and emissions should be to their advantage.

Cons: The battery pack and electric motor add weight and must go somewhere (normally under the back seat or boot) so expect a less nimble car and marginally reduced space.
A big issue is price compared to an equivalent non-hybrid model but this picture is changing rapidly as depreciation of diesels gets worse but those for hybrids improve and as the technology matures so it gets better and cheaper.

For company car drivers there are significant tax advantages to a hybrid.


Plug-in hybrids.

These can get their batteries recharged by plugging into a charge point either at home or one of the growing number of publicly available roadside/motorway service station ones. They work like the hybrids but with a plug-in port you connect to a recharging point to top up the battery while you are not using it.

 

 

Pros: A good and cheap way to recharge the battery when you are not using the car.

Cons: Not everyone has access to a recharger at home or work or has the time at a filling station, supermarket or public car park.


Range Extender (REX)

These are driven solely by an electric motor powered by the battery but have a little petrol engine as well which is there purely to recharge the battery pack.

Pros: Silent electric power only but because of the little i/c engine which you can fill up as with a conventional car there is no range anxiety.

Cons: You do have to pay a premium.


EVs

Pure electric cars only which run entirely on battery power.

 

 

Pros: The most eco-friendly, tax friendly of the lot.

Cons: Only works if you are confident you can reach a charging station before you run out of juice.


Fuel cell cars

These run on hydrogen which passes through a fuel cell to produce electricity for the electric motor.

Pros: As simple as filling up a car and cleaner than using electricity generated from a power station to recharge a hybrid battery. Should be the future.

Cons: When did you last see a hydrogen filling station?


Do they work for you?

Hybrids are a half way house until the world is fully geared up for pure EVs which is still a long way in the future. One day people will look back and wonder why our generation thought it was a good idea to have the cost, weight and complexity of a second engine in a car but for now, if you do mainly urban driving or perhaps have a second, conventional family car for longer journeys then a hybrid can be great and for company car drivers the tax case is getting better by the day.

 

 

Pure electric vehicles are a long way off for most of us as a practical car and there remain huge, valid and fundamental doubts about how people will be able to find a recharger, what the car’s second and third hand value will be and which garages will be capable of servicing them. However, most hybrids are as simple to drive as a normal car. The computer takes care of selecting the right power mode, battery, i/c or both, and there is a definite feelgood factor in driving along silently and smoothly on pure battery power.

The basic message is this. Legislation and tax are pushing us towards cleaner cars and hybrids are getting cheaper to buy and easier to run.

I will certainly look at one for my next family car.


Driving a hybrid BMW i3 Range Extender:

Driving a car like this could not be easier but is also a world away from what you might be used to in a conventional one. Select the `drive’ mode, release the electric parking brake and the i3 glides away just as smooth as silk. With no gears at all and just a little whine from the motor the i3 gathers speed effortlessly with maximum torque available as soon as you start moving.

If you want, but I suggest you don’t make it a habit, you don’t even have to touch the brakes to slow because as you lift off the accelerator the i3 will reverse the electric motor and using the car’s forward momentum put energy back into the battery. It’s called regenerative braking and is at the heart of every hybrid and is so effective that it will actually bring the car to a halt on its own.

 

 

The car does feel heavy because it has almost 100 high density battery cells under the cabin and so it is not the most responsive of things whenever the road turns. It rides on noticeably skinny tyres to cut the rolling resistance of a wider tyre which need more energy and you might think twice about the amount of grip available but it’s fine.

The i3 REX (does that sound kind of dinosaurish to anyone?) runs on the electric motor but has a little 650 cc two cylinder petrol engine acting as a generator for the batteries. It has its little i/c engine but can also be plugged into the mains via a normal domestic plug or a special BMW wall box installed at home or at one of the public ones. When I began the car was 100 per cent charged and showed 136 mile range and after a short, ten mile route of urban, dual carriageway and rural roads it has used just four per cent of its power. BMW claims that on a full charge it can do 276 miles.

 

 

The list price of my test car was £27,830 after the government grant given to push these ultra low emission cars and BMW says that the cost-per-mile is equivalent to that of a diesel but one capable of achieving 470 mpg. And no, that is not a misprint.

I don’t think I would be ready to buy an all-electric car. I am not an eco-warrior so my criteria would be cost and practicality and EVs are not yet there. But the day, for all of us, when they will be is getting closer.


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