The Renault Fluence ZE looks like a normal car from the outside. It looks like a normal car on the inside. When you're driving it it seems like a normal car. But the Fluence ZE is an electric car - one that Renault hopes will do for EVs (along with its Kangoo, Zoe and Twizy stablemates) what Toyota did for hybrids with the Prius.Back when we drove a prototype of the Fluence ZE back in the Summer we had a number of problems with the car we couldn't get past. With a lack of information over projected battery life, residuals, range and running costs it seemed hard to recommend, despite a government grant of £5,000 that takes the asking price down to £17,850.Renault has decided to offer the Fluence ZE with a leased battery pack that brings running costs back into the spotlight but solves the question marks over degrading or knackered battery pack - and residual values to a point.The Fluence ZE's battery pack can be leased at £81 per month for up to 9,000 miles per year. That might look a bit mean, but Renault rewards you the longer the lease - so additional miles cost relatively less.Renault also says that maintenance costs and insurance costs will be 20 per cent lower with the Fluence ZE than on the relative petrol or diesel models.What's more there's no road tax and no congestion charge to pay, which should make Londonites sit up and take notice. Break down and Renault will come and sort you out, free of charge. If they can't they'll stick you in a taxi or put you up for the night in a hotel.The French manufacturer reckons running costs, even with the leased battery and energy costs combined, should come in quite a bit cheaper than a petrol or diesel variant - around 15.5 pence per mile based on the lease agreement quoted above. The car is under warranty for three years; the drivetrain for five years but as long as you're leasing the battery it will be replaced.Now there's a little more clarity to those figures - and a lot more of an impression of how these cars handle and perform in real-world situations - we went back to test drive the Fluence ZE on its international launch in rainy Portugal. Renault Fluence ZE first impressionsThe Fluence ZE looks big, but not oddly-proportioned. It has a hint of the big backside that various alt-fuel cars have boasted over the last ten years, but mainly it looks like a family saloon. Its size is emphasised by a passing Volkswagen Bora though - a car that's nominally in the same small family saloon segment. The Fluence is much larger.Renault says the ZE version of the Fluence - there are combustion variants on the continent - are 'instantly recognisable' but they're not to be honest, which is probably part of the attraction. They're actually rather dull.There are blue-tinted details on light surrounds, a spot of badging, charging flaps on both front wheel arches - and some new rear lights that are actually very smart. Some slight aerodynamic and efficiency tweaks - the addition of Goodyear Efficient Grips for examples - are the only other exterior visual clues.So the big butt is the key giveaway, but it doesn't feel as large as it is and the Fluence proves a nimble and sure-footed drive around downtown Lisbon. The ZE weighs around 1700kg - quite a bit heavier than any other small family car - but it's not really apparent.The Fluence zooms off the line - all of the 166lb-ft (226Nm) of torque instantly available through the single-speed autobox - and the rev counter moves swiftly towards 80kph. It corners exactly how you'd expect any car of its size to corner; the ride is, perhaps, a little uncomfortable compared to other Renaults but not unsettled.That's until we encountered some wet roads. Pulling away at speed saw the Fluence ZE juddering down the road as ABS kicks in to prevent wheelspin after a downpour, something that other journalists noticed. It felt a little like there was not enough weight over the front wheels, but the Fluence ZE has a perfect 50:50 weight distribution, so we were flummoxed.The next day, in a different car, there was none of the juddering and we failed to replicate the phenomenon. Perhaps it was a one-off, but it's something to keep in mind. Renault says that ABS and ESC have been tweaked to suit the Fluence ZE's weight distributionWhen we drove a Fluence ZE prototype back in the Summer we thought the steering a tad light, like many cars these days. Perhaps it was a trick of the mind, perhaps the production models have been tweaked or perhaps it was the difference between individual cars but the electronic steering on the production Fluence ZE seemed a little firmer.That firms up the drive a lot more; the Fluence ZE feels much more planted as a result and handled far better than some heavier cars - coupe-cabriolets for example - do on twisty roads.Performance is intriguing in the Fluence ZE. Put your foot down and you will move, briskly off the line - and keep going until you reach the top speed.The 62mph sprint is north of 13 seconds, but it feels rather faster than that - and the virtually noiseless electric motor is an exciting novelty. Meanwhile the Fluence EV is limited to 84mph, but it felt capable of faster. 94bhp are available here at 3000rpm.There's very little that's different when driving an electric car, but the Fluence ZE's regenerative braking - recovering energy that would be otherwise lost when freewheeling - means there's a strong drag on speed when the accelerator isn't being used.It's so strong, in fact, that one should be able to complete the majority of drives without touching the brakes. That calls for an adaptation of driving skills perhaps not suited to today's high-pressure commute, but it's a much more relaxed way to travel and much better for the car's range.Because the battery is regenerated during periods off the gas, stop-start driving is much better for the Fluence's range - the exact opposite of how petrol and diesel cars perform on the road. Interior, gadgetry and specificationStep inside and you'll immediately notice a very different dashboard. Turn the key in the ignition and the only indication that the Fluence ZE is ready to roll is an electronic twittering and a small green light marked 'Go'.A dial gives a read-out of the electric car's current charge, rather like a petrol gauge, while another dial will tell you whether you're sapping the battery, regenerating the battery through engine braking or somewhere in the middle. It's a useful tool that gentles you towards driving in a manner beneficial to the car's range.Also noticeable is a factory-fit Carminat TomTom Live smart satnav - standard on all Fluence ZE models. This has been adapted so that it will show charging points and also has a useful 'balloon' feature that shows your range in all directions at any one time. Don't worry - it also shows petrol stations should you need to load up on any fuels other than fossil.There's cruise control available here, though it's not clear what its use does for fuel economy. Normally smooth, consistent driving is good for saving fuel; on the Fluence ZE that may actually harm charge levels if there's a lack of engine braking recharging the battery.Click here for more on Renault ZE warranties, batteries, drivetrains, sales and residuals Also standard on the Fluence ZE, with what is at present its sole Prime Time trim level, are 16” alloy wheels, six airbags and brake assist, climate control, Bluetooth and automatic headlight and wiper activation. Cleverly, a My ZE Connect Pack allows drivers to access various telemetry data on a smartphone or computer.Seats are comfortable, if not the most adjustable, and the cabin is airy, though Renault's current interior design seen across the range, hardly the most impressive on the market, takes the wow factor off the more exotic elements.There's good space for five in the cabin - and especially good space upfront. There are also plenty of cubbies around the cabin, including a nine-litre illuminated glove box.Open up the boot and there's 317 litres of boot space - not bad, not especially good; perhaps a little small for the small family car segment but equal to the ICE Fluence - and a very obvious battery unit. We managed to get luggage for two in there without problems.In the boot there's also a charging cable for wallbox and charging point, er, charging but if you want to plug in to your standard electrical socket you'll need to shell out for a different one. Running costs, range and the buying propositionCash and running costs are something of a fluid issue with the Fluence ZE. I can't really make the energy and battery leasing costs stack up against the fuel-only costs of similar-sized cars.Of course it's not as simple as that - but it's disconcerting to note that mid-range diesel models from the Megane range appear to best the Fluence ZE strictly on fuel costs. Renault quotes a per-mile battery-and-energy cost of 15.5p for one of the battery lease options (11 pence-per-mile plus £3 for a full charge that covers 115 miles), but an efficient diesel engine will consume less than 15p worth of DERV covering one mile - even at today's prices, edging inexorably towards 1.50 per litre.Of course, service costs, insurance, road tax and congestion charging will all be less on the Fluence - and oil prices are only going one way. On the other hand you need not shell out for a wallbox charging point (£799) or an extra charging cable (£414) with a diesel or petrol car.For the record I achieved 60km in the Fluence ZE without driving especially sympathetically and finished with around half a charge. That would suggest that 120km - 75 miles - is about right for the Fluence ZE if driven normally.That may not sound impressive compared to ICEs, which can frequently manage the best part of 1000 miles in large eco models, but the vast majority of journeys are well under this figure - Renault says nearly nine in ten journeys are around 37 miles, meaning you should have enough charge to go wherever you're going - and back - on one charge.It's here that we can see the Fluence ZE for its true worth. It's a school-run hero; a Tesco-trip specialist; a daily-commute champ. As a second car it may be the logical choice (although the Kangoo ZE may be even better for purpose): slap-bang in the middle of the market as far as list prices are concerned; a car that saves cash; is kinder to the environment (guesstimated CO2 figures suggest somewhere around 60g/km when energy generation is taken into account); packs in five plus luggage and is probably one of the easiest cars on the road to drive.Renault seems to have thought of everything. If you break down you get rescued free of charge. If your battery gives up - not that it should - you get a new one free of charge. Your maintenance and insurance costs will be 20 per cent cheaper than an ICE variant. Sell your Fluence and your battery goes with it - it's up to the new owner to strike a deal with Renault over the battery.You get preferential rates on hire cars for longer journeys. Experts at specialist centres will guide you in buying and maintaining your EV. Has a manufacturer ever attempted to make buying and living with a car so easy?At the most basic level the Fluence ZE undercuts EV rivals like the Nissan Leaf and Mitsubishi iMiEV significantly. The Toyota Prius - the real target for the Fluence - is at least two grand more expensive - while the forthcoming Vauxhall Ampera and Chevrolet Volt will also weigh in a lot dearer than the Fluence ZE.Renault has done much to answer the questions that our earlier drive in the Fluence ZE prototype threw up back in Southwark in the Summer. Should I buy the Fluence ZE?And yet, and yet... I can't help feeling doubtful. Residual values are still something of a concern. Without the government grant list prices climb to over £22,000. It's not clear that there's any financial advantage to buying a Renault EV over an ICE counterpart. The stumbling growth of an electric infrastructure is a worry. But, perhaps most important of all, I can't work out how the majority of car owners will charge their Fluence ZEs at home.I live in a terraced house. So do most people I know. Many others live in flats. I can't imagine how these people will charge their cars. Even those with larger houses and parking ports may find it easier said than done to charge their cars up every night. Will we really see a nation of roads, cables trailing from windows to Fluence and Kangoo ZEs and Leafs? I find it hard to envisage.In reality many of these problems can be reasonably easily, if not cheaply overcome. A specialist wallbox will cost almost a grand. A cable to charge from your domestic 220V power supply will cost almost £500. And a business car-park full of fleet Fluences - where 70 per cent of Fluence ZEs will end up - certainly makes sense.But when it comes to private buyers I don't think the nitty gritty of how and what and when matter. I think the perception - that electric cars are impractical and untested and a pain to live with - will out when people think about buying a new car.There is also a great deal of prejudice and deliberate misinformation spread about EVs. Renault has done everything it can in building high-quality electric cars like the Fluence and Kangoo ZE, making them viable - if still not obvious - purchases through the battery-lease programme and doing everything it can to smooth the way to electric for buyers.For the time being it will have to be enough. Renault (along with partner Nissan) is now leading the way with electric-car technology, in the way that Toyota has for hybrids. Now the rest of the market, business, media, government and buyers have to catch up.Whether you think the Fluence ZE is for you depends on a dozen calculations that only you can make. In isolation it's an impressive car; in the big wide world it might take a leap of faith to commit hard cash and thousands in battery leasing and charging paraphernalia to Renault's dream of an electric future. Renault Fluence ZE Milestones Fluence Z.E., Prime TimeCost: £17,850 (£22,850 with government plug-in vehicle grant)Battery leasing cost: Variable, from:£75 per month for 6,000 miles per year over 3 years;£81 per month for 9,000 miles per year over three years.Performance: 95bhp, 226Nm (166lb-ft) torque. Speed 84mph; 0-62mph 13 secondsRoad tax (VED): ZeroTheoretical average range: 115 milesCharge time: 6-8 hours from wallbox or public charging point; 10-12 hours on domestic power supplyPros: No-fuss, easy operation; straightforward driving; good interior space; certain financial advantages - no road tax or C-ChargeCons: Unclear if Fluence ZE makes sense from a financial perspective; smallish boot; uncertain handling in the wet