If you've designed a car that already looks like a nine volt battery, there's only one sensible course of action: run it on electricity.

That's the philosophy behind the Nissan Denki Cube, an all-electric concept unveiled this week at the New York show. Based on the shoebox-chic Cube, the Denki showcases Nissan's green intentions over the next few years... and the fruits of the design team's giant new Etch-a-Sketch board.

It's not quite a conventional Cube, though. There are just two rows of seats instead of three, and the metal roof has been replaced by a massive glass panel. We're not too keen on those 16-inch wheel covers, the lightning-bolt grille or the funny perforated bumper (anyone else reminded of a bourbon biscuit? No?) but hey - you hardly drive a bright white, square, electric car to stay anonymous.

Under the bonnet - well, under the floor and seats, actually - is a stack of laminated lithium ion batteries mated to an electric motor. Just like the Tesla Roadster, the Denki is all-electric and therefore theoretically zero-emissions.

Though the Denki remains a concept for now, Nissan reckons it can produce a hybrid by 2010, with an all-electric vehicle following soon after.

By which time, every vehicle on the road will be as square as the Cube. It'll be great. Multi-storey car parks will look like games of Tetris.