Renault is optimistic that production of its new electric vehicle range could reach as many as 100,000 units a year by 2014/15.

The aggressive prediction depends on continuing upward pressure on oil prices and positive tax incentives to encourage sales in Israel and Europe, Renault's main target markets, according to the company's environment director Alice de Brauer.

The estimate is around twice what it believes could be normal demand, around 30,000 to 50,000 a year, given less favourable fuel prices and tax conditions.

These figures give the first indication of the scale of commitment that Renault and Nissan are putting into EVs, a personal crusade of charismatic CEO Carlos Ghosn.

Ghosn now believes that the economic case for EVs has flipped in their favour after decades of never quite making their case.

Renault-Nissan is cooperating on electric vehicles and has made the biggest commitment to pure EVs of any major global carmaker.

Renault will initially convert three of its mainstream models - the Clio, Megane saloon and Kangoo light van - to electric power for the Israeli and Danish markets in 2011. Nissan will also enter those markets in the same year.

A year later both companies will launch a specifically-styled and engineered EV.

"Customers will have to recognise that it's a different-powered car," said Serge Yoccoz, head of EVs at Renault, "just like the Toyota Prius looks different for a hybrid."

The specific EV will share its basic platform with an Alliance vehicle and will feature a conventional pressed and welded steel monocoque body, rather than lightweight aluminium and composites.

"It has to be steel for cost reasons," said Yoccoz.

It will be around 4m long and have a practical interior for at least four people and a usable boot.

The unique EV will have also have a specifically-designed interior "with special plastics and that sort of thing", added Yoccoz.

Renault is aiming for a range of 100 miles in 'standard use' with at least 60 miles in 'tough conditions'.

Energy will be stored in lithium-ion batteries being developed in a joint venture between the Alliance and NEC, the Japanese electronics giant.

Re-charging time will be four to eight hours overnight for a full charge of a nearly empty battery but more likely will be two to four hours for a part-discharged cell.

Yoccoz's engineeing team are working to a simple, single goal - to make the whole life running costs of EVs cheaper than internal combustion engine cars.

He believes that ultimately the cost difference could be as much as 10% in favour of EVs when the cost of hydrocarbon fuel is added up over a complete life cycle, against the cost of electricity used.

Despite this major push into new green technology, Renault remains sceptical about hybrids.

De Brauer said they remain too expensive for the consumer for the amount of carbon dioxide saved.

She said a hybrid costs EUR600 per tonne of CO2 saved while an EV costs EUR200 per tonne of CO2 saved.

For similar reasons, stop-start technology for combustion-engine cars will be phased in across Renault's entire range starting in 2009/10.

"It costs just EUR50 per tonne of CO2 saved, so our decision is to equip all our cars with it, but only when the technology works smoothly for the customer."

Julian Rendell