OVER the past few weeks Renault has been giving politicians, journalists and big commercial customers across Europe the chance to drive a slightly odd-looking battery-powered vehicle based on its Kangoo, a small van. Like most of the latest electric-vehicle prototypes, the Kangoo Be Bop ZE, as it is called, drives briskly and quietly. Unlike most of them, it is a thoroughly practical proposition. It provides plenty of space for five people and their luggage, has a range of about 160 kilometres (100 miles)—and, crucially, when it goes on sale in less than two years' time, it will not cost a fortune.

Renault's roadshow is part of a vigorous campaign to prepare the market for the electric vehicles on which its boss, Carlos Ghosn, is staking the future of both the French firm and its Japanese ally, Nissan. Mr Ghosn believes that by 2020 purely electric, zero-emission vehicles will take 10% of the global car market. What is more, he wants such vehicles to account for 20% of Renault-Nissan's sales by then.

Mr Ghosn's fervour is missionary. He argues that with the world facing an unprecedented environmental crisis “those of us who make cars need to be part of the solution” and become “pioneers of sustainable mobility”. He is certainly putting Renault's and Nissan's money where his mouth is, committing €4 billion ($5.9 billion) and ring-fencing more than 2,000 engineers to work on the project.

How big a gamble is Mr Ghosn taking? At last month's Frankfurt motor show almost every big carmaker could boast of new hybrids in the pipeline, some of them plug-ins, and prototype all-electric vehicles were all over the place. Even hydrogen fuel cells still have their supporters. The German carmakers in particular, with their huge research-and-development budgets, are dabbling in all manner of different low-emission vehicles.

Not Renault. At Frankfurt, Mr Ghosn presented what he described as a complete range of affordable purely electric cars. There was a largish family saloon (the Fluence), a supermini-sized hatchback (the Zoe), the Kangoo Be Bop ZE and a wacky two-seat urban runabout (the Twizy). These were not mere show cars intended to test the reaction of potential customers. All are destined for production within two or three years. Mr Ghosn made no apologies for the silly names, but he promised that the cars would cost no more to buy than similar diesel-powered cars—after factoring in government tax breaks for zero-emission vehicles that in many European countries will be worth about €5,000. Their expensive lithium-ion battery packs will be leased. As long as owners drive at least 12,000km a year, overall running costs will be equivalent to, or lower than, a petrol or diesel-powered car.

Within the industry, the adjective most often used to describe Mr Ghosn's plan to make the Renault-Nissan Alliance the first big manufacturer of zero-emission vehicles is “bold”—in other words, somewhere between very risky and certifiably mad. In particular, most analysts consider Mr Ghosn's forecasts of demand for electric cars to be wildly optimistic.The French carmaker aims to be the first big producer of zero-emission vehicles

Tim Urquhart of IHS Global Insight, a research firm, reckons that purely battery-powered cars will command only about 0.6% of world sales in 2020, with plug-in hybrids accounting for a further 0.7%. Volkswagen, Europe's biggest carmaker, talks of 1.5-2%. The main obstacles, according to Mr Urquhart, are the comparatively short range of electric vehicles and the lack of places to charge them.

Renault's chief operating officer, Patrick Pélata, disagrees. With a range of 160km at launch the cars will, he says, satisfy the requirements of most people most of the time. In urbanised western Europe, 80% of journeys are below 60km, and 20% of cars in Europe—about 20m vehicles—never go any further. He adds that battery technology is undergoing a revolution, with more than 20 big companies worldwide competing to produce smaller, tougher and more powerful batteries. One reason for Renault's leasing model is to allow vehicle owners to upgrade their batteries as and when the technology improves.

Mr Pélata also thinks the problems with infrastructure are exaggerated. Initially, the majority of private owners are likely to be suburbanites, who will charge their cars overnight using domestic sockets, or fleet operators with predictable journey patterns. But Renault is also spending a lot of time talking to and doing deals with power companies and governments (which are under intensifying pressure to reduce emissions of carbon dioxide). He says that the money and the political will are there to install fast charging-points (which can deliver an 80% charge within 20 minutes) in car parks, workplaces and city streets. Renault is also planning to set up “quick-drop” stations that can swap a depleted battery for a full one in a few minutes.

Renault's commitment and attention to every detail is impressive, but Mr Ghosn's bet depends on three things working in his favour that he cannot control: the eager co-operation of governments; a rising oil price; and the willingness of drivers to change their habits. It is the last of these that is hardest to predict.