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Hyperloop, hydrogen-powered trains, and air-taxis. As the 21st century progresses, the way people get from A to B is on the cusp of a significant shift driven by design and innovation.

While the above technologies may be a few years off from widespread adoption, that’s not to say change isn’t already afoot.

Around the world, national and municipal governments are attempting to slash emissions and boost urban air quality, with many putting their faith in a growing sector: battery electric vehicles. 

There’s undoubtedly momentum behind the industry. A recent report from the International Energy Agency stated roughly 3 million new electric cars were registered last year, a record amount and a 41% rise compared to 2019.

Looking ahead, the IEA says the number of electric cars, buses, vans and heavy trucks on roads — its projection does not include two- and three-wheeled electric vehicles — is expected to hit 145 million by 2030.

If governments ramp up efforts to meet international energy and climate goals, the global fleet could increase further still, expanding to 230 million by the end of the decade.

A changing world 

As the number of electric vehicles on the planet’s roads increases, society will need to adapt.

Extensive charging networks, for example, will need to be rolled out to meet increased demand and dispel lingering concerns around “range anxiety” — the idea that electric vehicles aren’t able to undertake long journeys without losing power and getting stranded.

Another area where we will notice change relates to noise: As well as boasting zero tailpipe emissions, electric vehicles are far quieter than their diesel and gasoline cousins.

This means less noise pollution in urban areas — clearly a good thing — but also throws up a potential challenge for other road users, especially those with sight problems. 

“For people who are blind or partially sighted, judging traffic can be really difficult,” Zoe Courtney-Bodgener, policy and campaigns officer at the U.K.-based Royal National Institute of Blind People, told CNBC in a phone interview.

Courtney-Bodgener explained that an increasing number of “quiet” modes of transport were now being used, giving the example of bicycles and larger electric and hybrid vehicles.

“If you can’t always or reliably use vision to detect those vehicles, then sound is even more important,” she went on to state.

“And when the sound is not there, or is not loud enough to be able to reliably detect those vehicles, obviously that presents danger because … you’re not reliably able to know when a vehicle is approaching you.”

The law of the land

It should be noted that, around the world, legislation and technology have already been introduced in a bid tackle this issue.

In the European Union and U.K., for example, all new electric and hybrid vehicles will have to use an acoustic vehicle alerting system, or AVAS, from July 1. This will build upon and broaden previous regulations which came into force in 2019. 

Under the rules, the AVAS is supposed to kick in and make noise when a vehicle’s speed is under 20 kilometers per hour (around 12 miles per hour) and when it’s in reverse.

According to a statement from the U.K. government in 2019, the sound “can be temporarily deactivated by the driver if judged necessary.”

The EU’s regulation says the noise made by the AVAS “shall be a continuous sound that provides information to the pedestrians and other road users of a vehicle in operation.”

“The sound should be easily indicative of vehicle behaviour,” it adds, “and should sound similar to the sound of a vehicle of the same category equipped with an internal combustion engine.”

The RNIB’s Courtney-Bodgener told CNBC that while her organization was “happy” the AVAS directive had been translated into U.K. law, it did not “do all of the things that we want it to do.”

She went on to explain how the speed at which the AVAS cuts in perhaps needed to be increased to 20 or 30 miles per hour.

“We’re not convinced that if … a vehicle is travelling at, say 13 miles per hour, it would generate, on its own, enough noise for it to be reliably detectable by sound.”

Another area of concern relates to older vehicles. “There are already lots and lots of electric and hybrid vehicles that were produced before this legislation came into force and do not have the sound technology on them,” she said.

There was currently no provision to retrofit these, she added. “That is a concern because there are already thousands of vehicles on roads around the U.K. that do not have the AVAS technology.”

From the industry’s point of view, it seems to be content with the regulations already in place. In a statement sent to CNBC via email, AVERE, The European Association for Electromobility, told CNBC it supported the “current legislative status quo.”

“The limit of 20 km/h is sufficient, since at this level other noises — notably rolling tyre resistance — take over and are sufficient for pedestrians and cyclists to hear EVs and hybrids approaching,” the Brussels-based organization added.

“In fact, mandating additional noise beyond 20 km/h would rob European citizens of one of the primary benefits of electrification: reduced noise levels at city speeds.”

Noise pollution can indeed be a serious issue. According to the European Environment Agency, over 100 million people in Europe “are exposed to harmful levels of environmental noise pollution.” The agency singles out road traffic noise as being “a particular public health problem across many urban areas.”

On the subject of older cars needing to be updated, AVERE said: “Only a very small share of EVs on European roads would be subject to retrofitting requirements, given the fact that many existing vehicles have already been fitted with AVAS in anticipation of the new requirements, and that the rules have been put in place in time to support the expected mass uptake of EVs in coming years.”

If “additional requirements” were found to be necessary, AVERE said it stood ready to engage with policymakers.

The future

Discussions and debate surrounding this topic look set to continue for a good while yet and it’s clear that a balance will need to be struck going forward.

Regardless of whether one thinks the current legislation goes far enough or not, the fact remains these types of systems are set to become an increasingly important feature of urban transport in the years ahead.

Robert Fisher is head of EV technologies at research and consultancy firm SBD Automotive.

He told CNBC via email that testing conducted by the company had “found AVAS to be quite effective” but went on to add that if a pedestrian wasn’t familiar with the noise, “they may not automatically associate it with the presence of an approaching vehicle.”

“Currently, AVAS is mostly hindered by inconsistent legislation and a lack of innovation,” he said, before going on to strike a positive tone regarding the future.

“As we move away from the internal combustion engine, this technology has the potential to become a key part of a car’s character, a point of brand differentiation, and has the ability to save lives.”