Why the i3 and i8 are critical to BMW’s success

andrew Cars 2 Comments

BMW innovates with the i3 and i8

No, it’s not a new BMW model. When I say BMW, what is the first thing that springs to mind? The 5 series? The 3 series? M Cars? Well, leave that lot to one side for a moment, and pay close attention to BMW’s i series; the i3 and the i8, because these lightweight cars from BMW represent the future of automotive transportation. BMW is trailblazing.

BMW is a sorted company, they build reliable, efficient high-performance cars, and they make them interesting to drive; preferring the traditional segregated drive of a rear-wheel-drive format over the cheaper to produce front wheel drive design. This move makes them popular with driving enthusiasts, and those interested in fun chassis dynamics more than safety. But would you consider BMW a forward thinking company? Are they seen as an innovator in automotive terms, or a business stuck in the automotive past while everyone moves on to newer and better things?

Benefits of Mass Reduction

In 2011 I read a rather interesting book by Amory Lovins called Re-inventing Fire. Lovins is the Chairman of the Rocky Mountain Institute (RMI), a consultancy and think tank which looks at energy policy, and amongst other things, energy resources from a new perspective. I won’t tell you the whole story, but Lovins was getting very excited about ways to reduce US reliance on oil by investing in renewable energy. He mentions in the book that the single largest user of oil in the USA is transportation (73%). If you haven’t seen him in action, he is quite persuasive, and gives a good TED talk.

Now we all know that the US has never been forced to trim it’s waistline when it comes to fuel consumption. Woofling big block V8s are an American institution for god’s sake. Why would I drive a 2 litre 4 cylinder when I can drive a 357 cubic inch (5.8L) V8? Who cares about fuel consumption when oil costs tuppence a gallon? Precisely nobody. But those foreign wars don’t pay for themselves, and when a commodity becomes globally priced, it does make a difference. The US national debt isn’t getting any smaller.

The electric car has much to contribute towards the decarbonisation of the transportation system, but there is one point which limits the electric car’s widespread adoption. Well, two actually, but the first will improve gradually, the second we can do something about now. The first is energy storage; battery technology. The second is reducing the mass that the electric motor and batteries need to lug around.

Battery technology is always improving, in fact the roads may one day be like giant scalextric tracks, with cars being powered wirelessly from induction coils within the road surface or power transmitted from towers much as mobile phones work today, but until a truly wireless infrastructure is in place, we have a theoretical maximum energy density to play with. The lighter the car, the further the current battery technology will move it.

Lovins points out that the US got obsessed with car safety, and saw large cars as safe cars. Large cars need appropriately large engines to haul their substantial bulk around. So americans have been driving around in oversized vehicles ever since, with the option to buy lightweight efficient vehicles from Europe and Japan.

The Spiral of Increasing Returns

But if you make a car body lighter, you can make everything around it lighter too. If the car body is lighter, and if the motor provides regenerative braking, the brakes can be smaller (and therefore lighter), the battery store can be smaller, the electric motor can be smaller and the body’s mass can also be smaller. Using a stronger material with better energy absorption means it holds up better in crash protection too.

As the bodyweight shrinks, so do the ancillaries, which brings the weight down further. A lower vehicle weight with low slung weight can employ thinner tyres. Thinner tyres means lower rolling resistance and potential for improved range, which can reduce the battery weight even further. Reducing weight leads to a spiral of increasing returns.

Carbon Fibre Reinforced Plastic

There are many benefits to keeping weight low, but we need to use steel because it is strong enough to do the job. But how do you get lightweight car bodies that are also strong ? You use a material like carbon fibre reinforced plastic (CFRP). That’s what BMW has done with the i3 and i8.

BMW has plenty of F1 experience, and know plenty about carbon fibre. Sure they have made bespoke car parts out of Carbon Fibre, but with the i8 and the i3, BMW has partnered with SGL, a global carbon fibre manufacturer, to mass producing the i3 and i8 cars out of CFRP. This is a big step and one which points to the future of automotive design.

While the other car manufacturers; Nissan, Toyota and more recently VW are producing electric cars, or hybrid/ electric cars, they are doing little to change the infrastructure that the technology sits in, using the bog standard Golf platform, or a traditional steel monocoque to install an electric or hybrid powertrain. This is hedging your bets. This is testing the water. Meanwhile BMW has just leapt into the water shouting “cannonball!”

Do BMW know something the others don’t? VW is a big enough player to influence the marketplace with its manufacturing decisions, so I’m surprised we haven’t yet seen a brand new electric / hybrid small car design from VAG. Perhaps the success of the i3 and i8 will encourage more manufacturers to follow suit, perhaps BMW sees itself as a technical innovator, and is prepared to push the boat out.

BMW’s masterstroke has been to start from scratch. You can bet your bottom dollar that the i3 and i8 are over-engineered. Once these vehicles and the designs which go into them have been proven, their vehicle weights will fall further.

Are Electric Cars the Future?

Given the plethora of potential energy sources out there, is electricity really the future? It makes sense. It is the most futuristic energy source around. Put it this way, while we have learned to harness electricity and allow it to move from place to place, we don’t actually know where it comes from, neither do we understand what it is. Hundreds of years after its discovery, we still don’t really understand electricity. I’d say that is a future proof technology, wouldn’t you?

Why is electricity the future?

Electricity is the future because it is so versatile. One day not too far from now, we will be able to generate electricity ourselves on a domestic level. It is also universally available, must be high quality to make it into the grid in the first place, and can be used to power almost anything.

It is versatile: we can use fossil fuels to generate electricity, but we can also use nuclear power, as well as wind, wave and solar energy, and these recent renewable technologies are in their technological infancy. Imagine what will happen when a new type of solar panel is invented which can power a whole house, even on a cloudy day? It will change the whole dynamics of the fuel supply model, and electric cars will be king.

For now electric hybrid (range extender) gives all the flexibility required, and both the i3 and i8 are available with a miniature internal combustion engine to add flexibility; the i3 uses a twin cylinder scooter engine to recharge, while the i8 uses a heavily tuned 1.5litre three-cylinder engine producing 230hp to drive the rear wheels while the electric drives the front wheels.

What about Hydrogen?

I see hydrogen a useful intermediate step. Firstly it can easily be used as an energy store to capture the electricity that isn’t being used at the point of generation. Secondly, it lends itself to the internal combustion engine technology, as it currently stands.

Going from petrol to hydrogen is a much smaller leap than going from petrol to electric drives, so hydrogen is a useful intermediate technological step. I still see electric vehicles as the main drive moving forwards.

What is BMW playing at, have they gone mad?

Of course not. BMW knows how to build motorcars; good ones. They understand the fundamentals that go into making a good automobile. The main changes are to the power-train, the chassis rigidity, and the electronics.

By taking proven engineering principles and turning them on their head, BMW has asked the question:

“If we had an electric or hybrid power-train and we could design a chassis from scratch with lightweight CF as the chassis, what would a town car look like and what would a sports car look like?”

Answer: the i3 and the i8 respectively. The fundaments stay the same, it’s the constituent parts which change. The biggest learning curve is in mass production of carbon fibre.

BMW has seen a great deal of initial success with its i3 and i8 models. They have been well received and are real ‘halo’ models for the brand.

I am sure a lot of potential i8 buyers see it as a more tempting proposition than many performance cars, simply because it is leading-edge technology. If someone offered me a Lamborghini or a BMW i8 for a month, I’d pick the i8 hands down.

BMW really has demonstrated that less is more when it comes to vehicle weight, and I’ve no doubt that they are going to do extremely well with their dedicated i range of cars.

Borrowing from the tried and tested technology, the BMW C-evolution electric scooter uses three power modules from the i3 production car, bolted together which form the main chassis of the scooter. More below:

Keep a close on BMW, I think they’re on the right track. Even if other manufacturers try to steal a march on them in another direction, first to market is worth a lot.