Silent engines for electric cars were introduced to help relieving the noise pollution problem. Yet, the threat that the silent engine may pose to the vulnerable cyclists and pedestrians, especially the blind, has raised the concern of the public. The cost effectiveness of silent engine is also unknown. So, should electric cars’ silent engines be legalized worldwide? Is there any possibility in balancing the use of silent engines and the safety of road users?
For the Silent Engine in Electric Cars
According to the European Environment Agency, much of the noise pollution in Europe arises from traffic. Continuous exposure of such in a busy street can be harmful to human health, aggravating migraines and risks of cardiovascular diseases. Recognising these dire consequences, policy-makers passed laws to mandate continual efforts to quieten combustion engines1. Further, they negotiated the necessity of Acoustic Vehicle Alert System (AVAS), a device to emit artificial engine noises in cars with silent engines, to warn the blind of passing cars. AVAS had been a point of contention amongst EU policymakers. Noise pollution is therefore indubitably a negative externality that, since the introduction of AVAS and the focal discussion on silent engines, has been needlessly placed on the same scale as danger posed to visually impaired pedestrians. This creates a double-edged sword where safety and noise pollution become compromises of each other.
If we operate on system, how then do we ethically decide a balance between safety for the blind and noise pollution of the city? One may follow the Utilitarianism model to make an ethical decision based on benefit to the majority or lesser of two evils. Blind people are a minority of a population. Following this, for the majority’s sake, engines should be silent, AVAS be scrapped and any noise be minimal.
Campaigners concerned about silent engines assumed a fear that accidents involving hybrid cars will rise, yet there are evidence to show otherwise. Research showed that in Japan and Netherlands, there was no observed increase in risks2. Hence prohibiting silent engines so as to improve safety become a questionable.
In addition, AVAS and banning silent engines are not the ideal way to protect the visually handicapped. There exists alternative engineering solutions that yet do not incur costs on the majority. For example, the modification of current traffic lights, to give priority and more flexible time interval for the blind to cross the road. Such traffic lights already exist in Singapore, where the elderly and disabled people are granted longer ‘green man’ to cross when they tap their Greenman+ cards3. This shows silent engines should not be abandoned, as there are other solutions to protect the blind.
Such alternative solutions should be encouraged, instead of focal points on AVAS, silent engines or other parts of the electric car. The design, maintenance or prohibition of any car parts will inevitably incur monetary costs borne by agents in the market for cars. Cost of production will increase for car manufacturers, and consumer price of hybrid cars will increase in the market. However, safety is not a commodity whose costs should be borned by car makers and buyers. Safety should rightfully be ensured and monitored by the public sector and hence costs should be incurred into public goods, without affecting the free market for cars. As such, safety-related policies should be made to public goods such as road signs or traffic lights.
Against the Silent Engine in Electric Cars
Legalizing the implementation of silent engines in electric cars will threaten the safety of the drivers, the cyclists and the pedestrians, especially the blinds. The operation of the silent engine affects the driver’s awareness of the situation of their car engines. Consequently, drivers may lose control of their vehicles and lead to fatal traffic accidents much easier when comparing with diesel engine. The silent engine operates sounds like whispering which can hardly be heard by pedestrians. This highly reduces the consciousness of the pedestrians and the cyclists of the incoming of the electric cars, especially for the blinds. The blinds rely on hearing and the blind stick to guide their ways when crossing the roads. Many roads especially in UK do not have traffic sounding signal and may not even have traffic lights. Silencing the electric car engines thus strongly restrict the blinds from protecting their own safety through alerting the sound generated by the noise engines while crossing these roads.
According to the US Electric Auto Association, legalizing the silent engine requires an implementation of radar technology and Acoustic Vehicle Alert System that allows electric vehicles to detect when pedestrians and cyclists are in the vicinity of the car and engage the passive sound warning system. Putting such technology in use is not a cost-effective situation as each radar detector costs about USD30000 and electric cars are still uncommon in worldwide, like Hong Kong. Numerous drivers, pedestrians and cyclists are at risk in sacrificing their lives due to the doubtable necessity in attempting to reduce the noise pollution caused by the electric car engines nowadays.
In addition, silent engines of electric car are not yet well-designed for consumers in terms of low battery life span and high maintenance cost. Battery durability is the major determinant of the life expectancy of an electric car for its low life span. Some researches show that the car batteries are exhausted possibly within four to six years of functioning4. New batteries must be bought and installed for electric cars to work again, however, with a bulky size and heavy weight of hundreds to thousands pounds5, car batteries cannot be replaced by consumers in their own garages as easy as replacing spoiled components inside a diesel engine, rather, consumers need to seek professional help from maintenance lorry for replacement, which implies costly maintenance fees. Silent engines of electric cars, specifically the car batteries, should be better revised to ones with longer life spans before electric cars are available for sale. Otherwise, buying a new car component periodically every several years along with high maintenance costs not only harms the interests of consumers, but the generation of enormous metal wastes also possibly induces large-scale environmental crises.
55: Kiat Long Tay, Yuqi Wang, Hiu Tung Lam, Hok Lam Ting