New Brussels-based study investigates car obesity
A new joint study conducted in the Brussels-Capital Region (RBC) by the public service agencies Bruxelles Mobilité and Bruxelles Environnement has highlighted a worrying increase in car volume and weight.
This trend—also detected in the rest of the country and beyond—represents a serious threat to road safety, environmental protection, and social equity in our cities.
When public spaces, particularly road spaces, are perceived and used as spaces of conflict rather than sharing, it is tempting to hop on the narrative of 'the bigger, the better'—especially if one can afford it. This is just one of the many factors behind the spread of bigger, heavier, and taller car models like SUVs in urban contexts. The issue is that while purchasing such fashionable models is a matter of individual finances, everyone is paying the cost of generalised fleet bloating.
Under the strong impulse of Elke Van den Brandt, Minister of the Government of the Brussels-Capital Region (RBC) responsible for Mobility, Public Works, and Road Safety, Bruxelles Mobilité and Bruxelles Environnement have undertaken a scrupulous analysis of the situation in the RBC.
The results, some of which are highlighted in the image on the right, are staggering and make the case for urgent intervention to halt this spread of car obesity in both private and business-owned fleets, with a special focus on company cars (+248kg on average compared to private cars).
The impacts of car obesity
The freshly-released study highlights six categories of impacts brought by the increased weight of cars in the RBC on the Region's social and environmental goals:
- Zero road deaths and severe injuries: Taking cues from Vias Institute's statistical analysis on the effects of vehicles' characteristics on the severity of injuries reported by the opposite party, Bruxelles Mobilité has analysed collisions that occurred in the RBC between 2021 and 2022. It appears that even in an urbanised context where speed is limited to 30km/h on the majority of the streets, the weight of a vehicle has a strong impact on the consequences of the collision for the passengers of the opposite vehicle.
- More space for active travel, public transport and green areas: Although the modal share and ownership rate of private cars is decreasing in the Region, cars take up more and more public space. The study reveals that on average the width of cars registered in the RBC after 2018 is over 180cm, thus incompatible with the size of most parking spaces. As Brussels tries to prioritise active travel and boost green areas for better adaptation to climate change, this trend represents a serious hindrance.
- A just transition: The market segment of heavier and bigger cars caters to higher-income groups. The industry's focus on this segment comes at the expense of lighter and cheaper models, which would be accessible to a wider slice of society, and represent a tendency that is also mirrored in the electric vehicles (EVs) market. Considering that EVs in Belgium were found to be 14% heavier than the EU average, boosting the production of lighter and cheaper EVs is ever more pressing.
- Better air quality: Fine particulate emissions from road traffic represent a serious menace to public health and do not only depend on the type of fuel on which our cars ride. Exhaust emissions (those due to the wearing of tyres and brake pads, etc.) are strongly correlated to the mass of vehicles and need to be urgently reduced to ensure better air quality for the sake of citizens' health.
- Climate and energy efficiency improvements: The increased weight of vehicles balances out the reductions of CO2 emissions achieved by more efficient engines. Similarly, car weight negatively impacts the efficiency of EVs.
- Reduced environmental and social externalities: Producing bigger cars is naturally more resource-intensive, and this is even more worrying when it comes to the manufacturing of EVs, which implies the exploitation of materials with a high environmental footprint. Therefore, the enlargement of vehicles also enlarges the negative upstream environmental and social externalities of production.
The roots of the issue
The Brussels-based study has identified multiple factors, both at the national and European level, that are enabling and fueling this situation. As expected, these have to do with insufficient regulatory frameworks on the public side but also with production and marketing strategies on the side of private manufacturers.
Starting from the regulatory framework, it is noted that European regulations on CO2 emissions standards for new cars do not address the issue of increasing vehicle mass. Moreover, at the national level, Belgium's fiscal regime is oblivious to mass-related criteria in its support of EVs, while also favouring high-segment (and heavy) vehicles for company fleets. This lack of differentiation among EVs means that the positive impacts of the electrification of fleets risk being shadowed or even outweighed by mass increase.
At the same time, manufacturers are upholding a strategy of profit maximisation for vehicles sold, which means that they keep injecting new energy into the segment of heavier and bigger cars. Sustained investment in marketing campaigns showcasing models that are 'more emitting, heavier and more luxurious' is one of the reasons behind the popularity of SUVs, which have known a steady increase in number in Brussels.
The proposed solutions
In light of such a problematic scenario, Bruxelles Mobilité and Bruxelles Environnement have looked at examples from other cities and countries to propose measures that could help halt the car obesity trend.
In particular, they propose a categorisation of cars according to their mass which would go from vehicles 'very well-fit to an urban context' (<1000 kg) to 'absolutely unfit' (>= 2000 kg), factoring in a +300kg margin for EV due to the added weight of the battery pack. To ensure that the proposed measure duly accounts for social equity, they also envisage a supplementary margin or financial incentives to be put in place for large households, which tend to own heavier vehicles compared to the rest of the population.
Find the full study (in French) here
