There’s just 18 months to go before Renault plans to start rolling out its battery-electric car range, and the firm is gearing up to spread the message to the masses. Today it announced plans for an extended test-drive programme designed to let potential buyers sample the feel of zero-emissions motoring: “For many motorists, driving an electric vehicle will be a new experience,” Renault’s press release burbles. “The absence of noise from the motor, the immediate availability of peak torque and the linear acceleration curve mean that drivers will need to develop new habits.”

We’ve driven a few electric vehicles and can’t help feeling that Renault’s real motivation has more to do with marketing hoopla than any real need to re-educate drivers. There’s actually markedly less to do in most EVs than in their fossil-fuelled equivalents. Most don’t have gears, for example. All use regenerative braking to replicate or supersede the engine braking we are all used to from conventional cars, meaning that you use the brake pedal in much the same way or less. The steering wheel is a pretty standard device, as are mirrors, tyres, seats and belts. So unless Renault has done something bizarre we don’t know about, the test-drive programme must surely be more about re-aligning expectations than driving habits. It wants us (and its rivals) to know that its cars are nearly here, and it’s confident in its product plans.

Those plans include three cars in 2011. The first two will be current vehicles that will have undergone a heart and lung transplant, ditching the fuel tank and engine in favour of lithium-ion battery pack and electric motor. One will be the previously announced Kangoo Express ZE, due in the middle of 2011, the other will be a family estate car. These will be followed later in the year by a bespoke electric urban car, and in 2012 by a compact hatchback EV.

Oddly, although Renault has announced the test-drive programme, it hasn’t said how to go about booking a stint behind the wheel. We’ll see if we can find out more...

It feels all wrong, for a green car enthusiast, to be climbing into the garishly upholstered driving seat of a Chevrolet Equinox soft-roader. It’s a big, square, two-tonne blue box with reverse-Tardis packaging. The viewpoint is commanding, the steering wheel is on the wrong side, and the air-con is blasting away to tame the summer heat. Worse, the 4x4 proportions are just for show - this is a front-wheel drive car. All in all, it’s not a very promising prospect for keeping our CO2 output under control.

But this beast has got it where it counts, and we aren’t outputting any CO2 at all today. This is not just any Chevy - it’s a HydroGen4 fuel cell research vehicle. Somewhere behind us are three bulky carbon-fibre fuel tanks pressurised to a fearsome 700 bar, full of a surprisingly small mass of hydrogen gas. Just 4.2 kilos of the stuff is good for 200 miles, apparently. Under the bonnet is a 73kW electric motor, powered by a fuel-cell stack that splices the hydrogen from the tank with oxygen from the air to produce nothing at all but electricity and water.

Alongside us rides a minder from GM Europe, who seems surprisingly relaxed given that we are about to pilot this expensive prototype on the demanding Hill Route at Millbrook Proving Ground.

We take Loop 1 and 2 on the course, which takes in slopes steeper than 1 in 10 both uphill and down, plus some sweeping corners replicating a typical British B-road.

We weren’t sure what to expect from our first drive in a fuel-cell vehicle, and are almost apologetic to report that GM has succeeded in making the HydroGen4 highly unremarkable to drive. The only electrifying experience on offer would involve grabbing a handful of cables under the bonnet.

The car starts on a normal turn of a conventional key - silently, of course, except for a sudden rush of chilled air from the dashboard vents. We slot an ordinary auto-box selector from P into D, release the ho-hum handbrake, and we’re off.

Throttle response is instant, the urge on offer reasonable. It’s no sports car, but it’s no slug either. The regenerative brakes offer no feel whatsoever, but numbness probably comes as standard in an Equinox. The helm responds to inputs in the expected manner, with pots of power assistance and little precision.

Progress is smooth and very quiet, with the deliberately poor surface making no impact through the big tyres and soft suspension. If the gearbox changes ratios we don’t notice - they’re not often needed in a car powered by electric motor. The box offers no special ratio for steep descents, as you will find in a Prius or Civic Hybrid, which can both increase their rate of regenerative retardation to capture extra energy and to spare the brakes on a downhill stretch. As we crest a rise and are faced with a road that drops away like a tarmac-covered ski-slope, we ask our minder what the best technique is for keeping downhill speed in check. “Use the brakes,” he says, with a shrug.

Uphill is similarly straightforward. The motor, less beefy than the one that will find its way into the upcoming Opel Ampera, provides acceleration even when hauling the HydroGen4 up a 10% slope.

There’s plenty to argue about when it comes to hydrogen as a road fuel. It’s energy intensive to produce, requires more energy to pressurise, and in worst-case scenarios can account for more released CO2 per kilometre than petrol. On the other hand, if it can be produced from renewable energy, it offers the genuine prospect of zero-emissions motoring without the need for lots of lithium. It’s generating the renewable energy that is the hard part, of course. Plus there is the not inconsiderable hurdle of establishing a hydrogen refuelling infrastructure.

There is also plenty to argue about when it comes to fuel cells, particularly the staggering expense of making them at present. GM doesn’t say how much it costs to create the HydroGen4’s stack, but it’s likely to loiter in the region of $200,000.

So while we remain sceptical of hydrogen’s future as a fuel, there is not much to argue about from behind the wheel. It’s amply clear that hydrogen can be made to propel a car with no drama at all.

This time next week, on 16 June, Hugo Spowers will have unveiled the prototype of his vision for urban mobility. We don’t know exactly what it will be like, but it will be very small, very light, four-wheeled, two-seated and powered by hydrogen.

Spowers was the driving force behind the Morgan Lifecar project, which produced a lovely looking one-off vehicle and a lot of test data but nothing that punters could actually hope to sit in and steer. The new project, Riversimple, aims to produce an actual product.

Not that you’ll be able to buy a Riversimple Hyrban (or whatever the car is called after its launch). But you might be able to lease one. And Spowers has plans to ensure you’ll have somewhere to fill up with the lightest element in the universe for fuel.

What else do we know? The monocoque chassis will be carbon composite; the driving force will come from four in-wheel motors, doubling as regenerative brakes; it has a top speed of 50mph and a range beyond 200 miles. We also know that the fuel cell will have a very modest 6kW output, backed up by 20kg of ultracapacitors to store regenerative energy and to provide four-fifths of the power available for acceleration.

Spowers thinks this combination of energy storage options will conquer the usual problem with fuel-cell cars: not the scarcity of filling stations but simple cost. The fuel cell hardware currently loiters in the region of $2,000 per kilowatt output, and that price needs to fall by a factor of 40 to around $50/kW to be price competitive with internal combustion engines, according to our knowledgeable sources. Which is one reason why you won’t be buying a Hyrban.

We await the launch with interest...

Gordon Murray is still being very secretive about his upcoming small city car, codenamed T.25. As a report published this week demonstrated, journalists granted an interview with Murray are reduced to feeling the car through its dust cover, lest they uncover its charms before time.

Via that CBCNews Canada report, we learn that the steering wheel is “not in a conventional place”, something we suspected from the moment we saw photos of the foil-wrapped prototype’s swooping screen pillars.

“The internal layout is absolutely unconventional,” Murray told CBCNews. “You don't get in and out of it the normal way. You don't sit in it the normal way ... And certainly the shut lines on the body would give that away.”

All of which confirms that we should take at face value Murray’s recent patent application for a “compact seating arrangement”. The application asserts that Murray has dreamed up an unconventional layout, and in filing for a patent he has asked for legal recognition of its uniqueness, so that rivals will have to pay a fee to use the same ideas in their own compact cars until the patent expires. That’s assuming the application is approved and the patent granted. The Patent Office could decide the innovation is too obvious, or not original enough - more of which later.

So how will the T25 work? How will it cram four adults into a footprint smaller than a two-seat Smart?

Well, it won’t. The layout Murray wants to patent seats three adults, not four: one driver in a central position, plus two passengers seated behind and either side of the driver; the trio forming a triangle with its point facing forward. As the patent application goes on to explain, the height and the shapes of the three seats allow the occupants to be squashed together to a remarkable extent. Everyone will sit more upright than is the norm in a car, rear-passenger knees will slip into voids cut in the driver’s seat back. Passenger legs will stretch out either side of the driver as far as the front wheel-arches.

The arrangement has lots of advantages for a small car - it can be short and narrow and yet reasonably comfortable for all three occupants. The driver, in particular, will enjoy a footwell free of the intrusion and offsetting that so often blights the small car experience. The driver might get the odd dig in the ribs from a passenger’s knee, but all-round visibility will be great - better than in a Toyota iQ carrying three adults, where the front passenger sits further forward than the driver, compromising safety at junctions.

The snag is that the central driver’s seat might be tricky to sit in without a crouch and a scramble from the door, since it sits a couple of feet further inboard from the sills than is normal. Murray’s solution is to create headroom by removing part of the roof along with the door - hence his coyness about shutlines.

The other goal Muray has for his miniaturised runabout is nose-to-the-kerb parking, and the patent document acknowledges that each side door will need to open upwards, in Lamborghini scissor fashion or Delorean gullwing mode, or will need to slide out of the way like a van’s side door, taking a part of the roof with it.

Interestingly, we’ve seen much the same seating layout proposed by Heuliez for its promised three-seat electric car, the Friendly. Its doors do indeed slide completely out of the way, along with a piece of the roof - and a piece of the floor too.

What’s more, documents released by Heuliez show a very similar seating layout to the one proposed by Murray. In fact Heuliez’s computer-generated images would not look out of place alongside Murray's text.

All of which makes us wonder whether Murray will succeed in getting his patent.

However, we suspect that Murray has a few more tricks up his sleeve to reveal yet. After all, the sketches of the T.25 released at the start of the project (and at the one year mark) seem to be deliberately designed to throw us all off the scent, showing details that we now know are not going to feature in the car - such as a front-mounted engine. It’s reasonable to suppose that his patent application is far from Murray’s final word on the T.25’s innovations.

We’re not sure who has done best out of today’s deal between American electric sports-car startup Tesla and stodgy Teutonic wagen-maker Daimler, owner of Mercedes-Benz and Smart. For its $10m-plus investment Daimler gets a 10 per cent stake in Tesla, access to its innovative battery technology, plus a bit of rubbed-off sexiness. In return for a chunk of itself, Tesla gets the money, obviously, plus access to Daimler’s big-car-company engineering resources and a bit of rubbed-off solidity. Perhaps the Mercedes-Benz truck division might be able to furnish Tesla with a two-speed transmission that doesn't snap, for example.

The deal values Tesla at in excess of $100m, by the by, which is not bad for a company that's delivered not much in the way of product and nothing at all in profit.

We hope we'll see future products from both companies that are as exciting and innovative as the Tesla Roadster and as reliable and well engineered as an S-Class.

Hopefully we won't see Teslas that are as desirable as a Düsseldorf taxi. Or, for that matter, electric Smarts that cost a fortune, arrive late and don't work properly.

No, hang on, we already have the latter...

Well we got the price wrong. The ECC Evie electric car went on sale yesterday and costs from £16,850, not £15,000 as we’d hoped. Nearly 17 grand is a substantial increase on the C1's base list price of £7,795 – which is before the generous discount you can expect from a double-chevron dealer – and serves to underscore that lithium ion batteries remain as cheap to buy as Jimmy Choo shoes.

ECC’s swanky London launch was attended by lots of people in suits, seasoned with the odd journalist or indeed blogger standing out by virtue of their sartorial slumming and canapé cramming. The suits were mostly potential customers or partners – we small-talked with people from a breakdown provider, an energy company and a local authority.

We are still waiting for some basic facts about the Evie – we don’t know how much power or torque its electric motor produces, for example, although we can tell you that it doesn’t feel like there’s much of either under the bonnet. Drivers hoping to explore the Evie’s 60mph top speed will be in for a long wait.

The car does look and feel well put together, though. The interior is pure Citroen, with the existing gauges and controls. There’s still a tiny petrol pump symbol next to the LCD gauge that now shows battery charge, for example. And because the batteries aren’t lumps of lead, weight and weight distribution are good – at 900-odd kilograms the car weighs about the same as a standard C1 plus a fat friend. It all feels very comfortable and normal. Even the hot air blower works, by virtue of an immersion heater in the existing matrix, apparently, now that the waste heat from the engine coolant is no longer available.

Lifting the bonnet reveals a nondescript black box and chunky cables plus, surprisingly, the car’s original lead-acid battery. This presumably powers the ancillaries like lights, wipers, heated rear window and stereo.

We weren’t allowed to drive the car for long enough to get a real feel for it, unfortunately, due to coming low on the totem pole of people likely to buy one. We find the price a little offputting – “We can’t get round the cost,” admits ECC big cheese David Martell, wishing that the government’s promised £5,000 subsidy were available right now. It may help if you’re buying on the company tab or with the public purse, and where there are tax breaks and writedowns and PR spinoffs and things to ease the invoice through. Martell hopes to shift 500 in the next 12 months and several thousand the year after, in the UK, Spain and France. We worry that 500 might be a bit optimistic.

We liked the car, though. We wish it were a bit faster off the line, and if we’re brutally honest we’d prefer it based on a Toyota Aygo. Yes, the C1 and Aygo are the same under the skin, but it’s the Citroen’s skin – well, its nose – that reminds us of a pig. And in a swine-fever-gripped world, snouty is not a good look.