There is about to be a seismic shift in the urban landscape. Within the next five to seven years, some 55 percent of the world's population will live in the city, threatening total gridlock. Unless something is done, the irony of the phrase 'personal mobility' will be self-evident. Look around at the cars in a typical city traffic jam today and the vast majority will have only one occupant and four empty seats. Some might have two occupants, a few three. But find one with four occupants or more and you'll be doing very well. Today, we buy a family car knowing that we'll only ever need to use it to its full potential one or perhaps two percent of the time. Tomorrow, things will be different. Tomorrow, things have to be different.
Nissan's vision for the future of urban transportation is encapsulated in Nuvu, a 'new view' of the type of car we will be driving in the middle of the next decade. Compact - it's just 3 metres long - Nuvu is a concept vehicle with unique 2+1 seating. It is aimed at urban dwellers who don't want to compromise on their personal freedom or their comfort, yet who appreciate that 'something has to give.' Nuvu is agile, easy to drive, even easier to park. And it is, of course, an electric vehicle (EV). Nuvu is described as a moving oasis, a haven of green tranquillity in the urban jungle. To underline this message, Nuvu incorporates a witty representation of its green credentials: across its all-glass roof are a dozen or so small solar panels. Shaped like leaves on a branch, the power they generate is fed to the battery using a 'tree trunk' within the car as a conduit. Nuvu also uses natural, organic and recycled materials within the cabin.
Nissan has already announced plans to introduce an all-electric car in Japan and the US in 2010 and to mass-market it globally in 2012. Nuvu is not that car, though it does share some of the technology that will feature in the planned production vehicle. Rather, it is a concept of how a Nissan EV might look in the near future. In the longer term, Nissan foresees a future based around a line-up of zero emission vehicles regardless of their size, category and usage. Nuvu - or its production equivalent - is just one element of this emission-free future.
The central thrust behind the development of Nuvu is not its motive power but its layout and use of space. Nuvu has been created for a city of the future, one that's even more crowded than today. That's why it's compact on the outside yet roomy on the inside. Built on a unique platform, it's just 3 metres long and sits on a wheelbase of 1980 mm but is 1700 mm wide and 1550 mm tall to create a large and airy cabin.
These dimensions provide all the interior room needed for the vast majority of city journeys. Nuvu has two regular seats and a third occasional chair that can be folded down when required. But, unlike some two-seater city cars currently on the market, it is a thoroughly practical proposition with an integral luggage area providing sufficient space for a typical supermarket or shopping expedition.
The packaging is designed to give priority to driver comfort with C-segment levels of space and the flexibility to invite one or two passengers on board. Cabin layout places the regular passenger seat beside but largely behind the driver's seat, allowing the passenger to stretch right out. Ahead of this seat is a third occasional chair which, when not in use, is folded away into the dashboard assembly. But even when the third seat is in use, there remains sufficient legroom for both passengers.
In the interests of saving both weight and space, the third seat has a centre section made from hardwearing yet comfortable netting. This hammock-like approach also has the benefit of allowing cool or warm air to circulate around the occupant's body for extra comfort. Shopping bags, briefcases and smaller items of luggage can be stowed behind the driver's seat while if the driver is travelling solo, larger items can be stowed in the passenger footwall.
Many of the materials used inside Nuvu reflect an increasing concern for the environment. The floor is made from wood fibres pressed into laminate sheets and is studded with rubber inserts made from recycled tyres for grip. To create a light and bright interior, the windscreen and roof merge into one extended panel running virtually the entire length of the car. But undoubtedly the most unusual feature of the interior is the 'energy tree' which rises from the luggage compartment floor to the roof behind the driver's seat.
The energy tree is shaped like a thin trunk. As it reaches daylight it branches out under the glass roof providing occupants with protection from bright sunlight... just like a real tree. And providing a visual reminder of Nuvu's green credentials, covering the branches are dozens of small solar panels shaped like leaves. The panels absorb energy from the sun which is then fed back down the energy tree and used to help recharge the battery and provide an extra power boost for the electric motor. As well as being genuinely green energy, it is estimated that the power generated via the solar panels will save the equivalent of one full overnight charge from mains electricity each month.
Nuvu is more than a styling concept of a future EV. It is a fully working mobile test bed for much of the technology that will be used in Nissan's production EV to be launched in 2010. For this reason elements of its technical specification are being kept secret for the time being. The electric motor used in Nuvu is mounted at the rear of the vehicle and drives the back wheels, though neither its exact specification nor the power and torque figures are being released at this stage. A driving range of 125 kms and top speed of 120 km/h are being made public, however.
Similarly although it can be revealed that the batteries used are of the latest laminated lithium-ion type and have a capacity of 140 Wh/kg (watt-hours per kilogram), the total capacity of the batteries and number of modules are not being disclosed at this stage. Nissan began research into high output Li-Ion cells as long ago as 1992, but today development is carried out by Automotive Energy Supply Corp. (AESC), a joint venture company set up by Nissan and NEC Group.
Unlike a conventional lithium-ion battery with its bulky cylindrical cells, the laminated Li-Ion battery as used in Nuvu has thin laminated cells and fewer components overall. This boosts its power by a factor of 1.5 at the same time as halving its physical size. It also remains twice as efficient as a conventional cylindrical Li-Ion battery even after five years or 100,000 kms of continuous usage.
Although clearly a concept vehicle exploring aspects of future vehicle design, Nuvu nevertheless embodies many messages for today. Its clever interior provides ample headroom, legroom and comfort for most everyday needs without occupying more road space than it needs. The use of recycled and natural materials underlines Nuvu's environmental message and while the energy tree might be considered as a piece of whimsy, the use of solar energy is an entirely sensible and practical technological solution to aid an emission free future.