The near-silent operation of electric cars could bring a welcome reduction in noise on busy roads, but it also poses a risk to pedestrians and other vulnerable road users.

Nissan has developed a 'noise' for its Leaf, which goes on sale in the UK next year, so that pedestrians and cyclists can be alerted to its presence.

The appropriately named Approaching Vehicle Sound for Pedestrians (AVSP) system uses frequencies ranging from 600Hz to 2.5kHz, depending on the speed of the car and whether it is accelerating on decelerating.

Luckily you don't have to imagine what that sounds like because Nissan has released some footage of AVSP in action

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Nissan says the frequency of the noise is enough to alert pedestrians and cyclists to the presence of the car without adding unnecessary noise pollution to the environment. Judge for yourself.

The noise, which is controlled by computer and generated by a speaker in the engine compartment, can be temporarily switched off.

Lotus has also developed fake sounds for its plug-in Evora concept car, although it's mainly for the benefit of the driver. The Evora 414E's Halosonic sound system can generate the sound of a V6 or V12 engine, along with a futuristic noise like a fighter from Star Wars, according to the company.

What noise do you think an electric car should make?
Mobile ringtones and celebrity voices for sat-nav systems have proved popular with consumers, but what noises do you think would suit electric cars such as the Leaf?

If you could have your electric car make any noise, what would it be?

Send your suggestions, and any short sound files, to us at
Whatcar.com

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 While 60% of male drivers would drive less to slash motoring bills, fewer than half of women would abandon their cars to cut costs, according to new research from the Environmental Transport Association (ETA).

Fast women
The survey also revealed that 45% of men would drive more slowly to cut fuel costs, but just 37% of women would lift off the accelerator to reduce bills.
However, women are 23% more likely to combine journeys to reduce their overall mileage.

Regional comparisons:
• Drivers in the North East were least likely to drive less to cut their motoring costs, but the most likely to reduce their speed.
• Drivers in the South were 46% more likely than those in the North to cycle in order to save money.
• Drivers in the West Midlands were most inclined (61%) to drive less.
• Drivers in the East Midlands were least likely (31%) to reduce their speed to cut motoring costs (31%).
• Drivers in the East of England showed the most enthusiasm for the idea of cycling more to reduce costs.

Other findings:
• Twice as many men as women are prepared to cycle in order to reduce their motoring costs (21% and 10% respectively).

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 Children arguing in the back of a car can impair the driver's skills as much as alcohol consumed to the legal drink-drive limit.

Squabbling kids extend reaction times
The report ? carried out by the Transport Research Laboratory (TRL) for insurers Direct Line ? revealed that drivers' reactions times slowed by an average of 13% when squabbling kids were in the car, the same as for those who had drunk the 80mg/100ml legal limit for alcohol.

The reduction in reaction times is enough to add four metres to stopping distances when travelling at motorway speeds.

The research also found that the distraction of bickering children led to 40% more instances of hard braking, and increased stress levels by nearly a third. Previous research by the Health and Safety Executive revealed that stress also increases the likelihood of being in a collision.

Senior TRL researcher Dr Nick Reed said: 'There was a noticeable impairment to driving caused simply by the noise of arguing children. Precautions should be taken.'

How to survive kids and the summer
Direct Line has some tips

on keeping kids happy, while you can also read our Summer Survival Guide

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 Suzuki has revealed its all-new swift supermini, which goes on sale in the UK this autumn from around £9500.

The car is bigger than the current Swift in every dimension except width ? where it shrinks by 5mm ? while more use of high-strength steel makes for a lighter, stiffer body shell.

More dynamic
With a wider track front and rear, plus lower-profile tyres, Suzuki promises the new Swift will be better to drive. The interior of the car is also designed to have a more dynamic feel, although no photographs of the cabin have been released.

Eventually, two new engines will power the car, but initially it will be available with only a 93bhp 1.2-litre petrol unit. The new engine returns 7.8mpg more than the current 1.3 engine ? with an average of 56.5mpg ? while emissions are down 24g/km to 116g/km.

A 1.3-litre diesel will also be offered from early next year. It returns 4.5mpg more than the unit it replaces, with an average of 67.3mpg, while emissions drop from 119g/km to 109g/km.

Full specification and pricing will be announced closer to the car's arrival, but we'd expect the Swift to start at around £9500.

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 These computer images show what a smaller, mid-engined brother to the Audi R8 could look like.

Our image of the car, which is likely to be called R4 if it's given the go ahead, is based on Audi's electric e-tron concept car revealed at this year's Detroit motor show.

While electric and hybrid powertrains are being developed for this and other cars in the Audi range, the small, lightweight coupe is also certain to get conventional petrol and diesel engine options from launch, which could be as soon as 2012.

To minimise cost and maximise profits, the R4 would share the same underpinnings as the Volkswagen BlueSport roadster concept car

, which was unveiled at the 2009 Detroit motor show.

The BlueSport is powered by a 178bhp diesel engine, which, given the car's low weight, is capable of blasting it from 0-62mph in 6.6 seconds and on to a top speed of 140mph.

Entry-level Porsche?
To get more out of the technology, the BlueSport platform could also be used for a new entry-level Porsche.

Check out our gallery to see pictures of the e-tron and BlueSport concepts, and computer images of the R4 and baby Porsche Boxster.

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 Cheap child seats can give your children more protection than models costing twice as much, according to preliminary tests by the Transport Research Laboratory (TRL).

Using its newly developed five-star Child Seat Rating Scheme, which involves crash-testing seats and assessing their ease of use, TRL gave a seat costing £39.99 a four-star rating and another costing £89.95 just one star.

While a one-star seat still meets the United Nations ECE R44 regulation required for sale, a five-star seat 'delivers exceptional performance in safety and usability' says TRL.

None of the seats in TRL's preliminary tests have been named because the results are designed to show how the rating system will work when it is rolled out later this year.

The test will make comparative point-of-sale information ? showing the relative performance of seats ? available in shops for the first time.

The test puts each seat through a frontal and a side impact, and also evaluates how easy they are to use, because an incorrectly fitted seat offers less protection.

TRL's demonstration tests were all carried out on typical entry-level Group 0+ seats for infants costing £100 or less. The first official results are expected to be announced later this year.

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 What is it?
The ?green? version of Seat?s small family hatchback

What?s new?
The Leon Ecomotive now comes with a 1.6- rather than 1.9-litre turbodiesel engine. An engine stop-start system has been added, too, while energy normally lost under braking is also recovered. As before, the Ecomotive version has different gearing and special tyres to boost efficiency, along with an aerodynamic pack to help it cut through the air more cleanly.

The end result? CO2 emissions of just 99g/km and average fuel economy of 74.3mpg.

What?s it like?
Apart from the stop-start system ? which works smoothly ? the Ecomotive is just like any other Leon from behind the wheel. The ride is a little firm, but the handling and steering are sharp. The 1.6-litre diesel engine isn?t as quiet as it is in the closely related VW Golf, but it?s impressively flexible and smooth, nonetheless.

How much does it cost?
In S trim the Leon Ecomotive costs £16,840, which is a lot cheaper than the equivalent VW Golf Bluemotion or Ford Focus Econetic. Standard kit includes air-conditioning, a USB port and six airbags. The SE version ? which adds extras such as alloy wheels, cruise control and a plusher interior trim ? costs £18,140. The Leon Ecomotive is on sale now.

What Car? says?
Impressively green and affordable

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 We sometimes use computer-generated images to show the design of new cars before they're officially unveiled, but how accurate are such images?

This image shows what the estate version of the new Astra could look like, but you've only got a week to wait to see how close our artist has got with his interpretation of the car.

Although the Astra estate makes its debut at the end of September at the Paris motor show, the company is to reveal the first official pictures of the car next week.

Well revisit our computer images then to compare the two.

The new Astra estate will go on sale at the end of this year or early in 2011 for around £16,700.

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 This is Renault's new upmarket Latitude, which will make its first European appearance at the Paris motor show in September.

The flagship Renault is bigger than the Laguna and is designed to put comfort, convenience and class at the top of the agenda.

It has triple-zone air-conditioning, a massaging driver's seat, a Bose stereo and hands-free entry and engine start.

Once-bitten?
The Latitude will go on sale in various countries from the autumn, but no decision has yet been taken on whether Renault will bring it to the UK.

The company's previous executive car, the Vel Satis, was unsuccessful ? just over 100 of the cars were sold in its final year on sale in the UK.

It has also been difficult for other big French saloons in the UK: Peugeot no longer sells the 607, while Citroen C6s are scarce on the roads.

A decision on whether to sell the Latitude here will be taken in the next few months. If it does arrive it's likely to cost from around £24,000.

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