Conceptualising Micromobility: The Multi-Dimensional and Socio-Technical Perspective

1. Introduction

Globally, micromobility could be more important than electric cars in reducing transport’s stubbornly high carbon emissions (IEA, 2021). It also brings positive social and economic benefits aligned with a range of Sustainable Development Goals (United Nations, 2015). It could thus play a central role in transitioning to lower carbon mobility (Moradi & Vagnoni, 2018). Despite this significance, the term micromobility is not well conceptualised in the academic literature.

Industry analyst Dediu (Micromobility, 2017) is widely credited for coining the term micromobility in 2017. The term has gained currency very quickly over the last few years, in policy, industry and academic contexts, with multiple definitions and understandings of the term. However, a detailed conceptualization and broadly accepted definition are still missing. The emerging body of literature on micromobility is largely based on empirical studies and definitions of the term are typically short, usually limited to listing a range of micromobility modes, or a focus on weight and speed characteristics (see section 3). Debates closely related to micromobility (see section 2) tend to be only weakly linked with considerations of the term micromobility. This paper addresses these gaps and proposes a new conceptualisation of micromobility that goes beyond vehicle -based definitions to provide a broad socio-technical approach and multi-dimensional understanding of micromobility. which, controversially, includes walking (sections 4 and 5).

Some of the mobilities commonly understood as micromobility, such as shared electric scooters, are a relatively new additions to our cities and have been adopted fast in some countries. Other modes, such as bicycles have been around over two centuries, having gone through phases of mass-scale uptake, followed by decades of marginalization before the recent phase of popularity and further technical development (e.g. e-bikes). This means that, while the term micromobility may be new, many modes that may be considered ‘micromobility’ - such as walking, cycling or use of scooters - have long and rich histories of policy, industry, and academic debate (Ploeger and Oldenziel, 2020; Dekker, 2021).

While some modes typically understood as micromobility (e.g. cargo bicycles) have been marginalized because they did not ‘fit in’ to mainstream categories (see e.g. Cox, 2012), others (such as wheelchairs or mobility scooters) are largely absent from the debate because they largely serve particular groups, or because they are mainly only popular in the ‘Global South’ (such as Tuk-tuks, Boda Bodas).

Walking is rarely discussed as constituting micromobility. As this paper follows a socio-technical approach, or a ‘beyond vehicle’ perspective – integrating technologies with social practices – we argue for integrating pedestrianism. Walking is also ‘micro’ in terms of environmental impact and land use, while being a central mode for most people. Including walking could provide new alliances within transport debates (see section 2) and strengthen the argument towards post-automobile low-carbon mobility futures across the globe. Globally, and historically, walking is central to most people’s mobilities. Even drivers and air travellers cannot reach their cars or planes without walking to them.

The (re-)emergence of micromobility comes with many contestations, for example around safety, road space and legislation. Conflicts between pedestrians and shared e-scooters are one example. Policy makers often scramble to provide frameworks within the dominant (auto)mobility frameworks, like allocating small amounts of space, often creating conflict with other micromobility modes such as walking or cycling. More radical approaches re-allocate automobile infrastructure, with an acceleration during Covid-19 in some places. Overall, the legal frameworks for micromobility vary, and are changing rapidly.

Our conceptual approach to micromobility is informed by a mobility studies perspective, seeking “to address entire mobility systems, logistical practices, energy cultures, and the way everyday practices are embedded in these larger socio-technical systems” (Sheller, 2018a, p. xv). We take a socio-technical perspective where systems such as mobility “consist of a cluster of elements, including technology, regulation, user practices and markets, cultural meaning, infrastructure, maintenance networks and supply networks” (Geels, 2005). This paper’s main research question is thus: How can we best conceptualise micromobility in a socio-technical and multi-dimensional manner? To answer this question, the paper reviews micromobility-related concepts (section 2), analyses the emergence and use of the term micromobility in the academic literature (section 3), proposes a socio-technical conceptualisation of micromobility with seven dimensions (section 4), and contributes a new micromobility definition (section 5), followed by the conclusion (section 6).

2. Micromobility-related concepts

This section reviews concepts that are closely related to micromobility: active travel, non-motorised transport, powered two-wheelers, electric mobility, Light Electric Vehicles (LEVs), multi-modal transport, shared mobility/Mobility as a Service (MaaS), and smart mobility. They were selected based on the expertise of the co-authors and in consultation with senior scholars. While there are tensions between (elements of) some of these concepts, we mainly focus on potential synergies. The limited amount of interaction between many of these concepts (e.g. between active mobility and LEVs, or non-motorised transport and electric mobility) results in research, innovation and policy in rather siloed ways. Similarly, whilst the term micromobility may facilitate debates across these concepts, the current lack of a broadly accepted conceptualisation and definition exacerbates confusion and causes misalignment across agendas. Our definition of micromobility, with its dimensions and characteristics (see sections 4 and 5), builds on this section’s concepts and intersections between them, thus embedding micromobility within a broad set of literature, disciplines and policy agendas.

2.1. Active Travel

The term ‘Active travel’ (or mobility/transport) comes from the public health field and covers modes that require some physical activity, such as walking and cycling. More recently, active mobility debates have started to include assisted modes such as electrically-assisted cycling (Sundfør et al., 2020). The ‘active’ element of other modes of micromobility (such as e-scooters), where users stand up rather than sitting down and push off to get started, is less explored in the literature. Significantly, one major mode of active travel, walking, is typically not included in micromobility definitions and debates. Instead, tensions are often described, e.g. between pedestrians and e-scooters (Fitt & Curl, 2020).

Most active modes tend to be considered as micromobility, depending on definitions (see below). Yet, micromobility can also include modes excluded from active travel, such as electric mopeds. Nevertheless, the physical activity and associated public health dimension are key for considering the societal and individual relevance of (specific modes of) micromobility, while it is important to keep tensions, alliances and synergies between walking and (other) micromobilities in mind.

2.2. Non-motorised Transport

The concept ‘non-motorised’ transport/mobility comes from the transport field and has been around since the 1970s. It has some overlap with ‘active’ debates, e.g. in terms of focusing on walking and cycling – and is often used to group these modes for modelling purposes. It is a key concept used by organisations, especially those focussed on the Global South, such as the UN (United Nations Environment Programme, 2019). The term is complicated by the emergence of electrically-assisted modes such as e-bikes that are partially human-powered and (optionally) partially powered by an electric motor. It would be interesting to explore how a micromobility grouping in transport modelling could provide new insight into potentially achieving low-carbon futures. IPCC reports indicate the high feasibility of non-motorized transport as an important mitigation and adaptation option for climate change (de Coninck et al., 2018, pp. 16–17). This underlines the importance of linking micromobility debates with those on non-motorized transport and strengthens the argument for including walking in a definition of micromobility.

2.3. Powered Two-wheelers

The debate on powered two wheelers (PTWs) – motorcycles, mopeds and scooters –is of particular importance for the Global South, where they are the most prevalent vehicle type in several low- and middle-income countries (Gutierrez & Mohan, 2020). Related accidents fatalities are high, making safety research a particularly strong focus (O’Hern & Estgfaeller, 2020). PTWs are often used for transportation of passengers and goods, both in dense urban areas and in rural off-road contexts, increasingly facilitated by mobile phone services. Moped and scooter type PTWs fall under most understandings of micromobility, and provide an important Global South perspective, yet links between both debates remain scarce. Within debates on e-mobility in the Global South, electric two-wheelers are often identified as the most promising vehicle type (Rajper & Albrecht, 2020), confirmed by current market growth.

2.4. Electric Mobility

As many of today’s micromobility modes are (sometimes optionally) powered by an electric motor, wider debates on electric mobility are also relevant to micromobility. Electric mobility is often conceptualised narrowly in terms of electric cars (Behrendt, 2018). Mapping the interactions between electric modes – whether 'micro' or otherwise (see definition below) – is an important prerequisite for broadening and accelerating the electric mobility agenda. A switch to electric cars is also often regarded as the main route to reaching climate targets without re-thinking automobility – a strategy which is likely to be insufficient (Henderson, 2020). Instead, a broader, micromobility-inclusive understanding of electric mobility would have a better chance of achieving carbon reduction goals.

2.5. Light Electric Vehicles (LEVs)

The term Light Electric Vehicles (LEVs) covers many of the mobilities that fall under the umbrella of micromobility, e.g. “electric bicycles, 3- and 4-wheelers, skateboards and segways” (Hyvönen, Repo and Lammi, 2016, p. 258).Others define LEVs as vehicles that fall within the UNECE’s M1-category (Ewert et al., 2020) or the EC’s L (European Commission, 2022) with specific attributes and categories. These varying LEV definitions do not cover fully human-powered vehicles such as bicycles or practices such as walking, and some do include quite heavy vehicles. Adoption is uneven globally, with “considerable market share in Asia, [while] LEV sales in Europe are still very low” and research with a global perspective very much missing (Ewert et al., 2020, p.2) while “outdated” and “inaccurate” regulations are currently a bottleneck (LEVA-EU, 2022) – concerns that both LEV and micromobility advocates share.

2.6. Multi-modal transport

Micromobility options, particularly shared e-bike and e-scooter schemes, are often used as access or egress options for modes such as public transport (Oeschger et al., 2020). Multi-modal transport research, especially with a focus on integrating with active modes, is key for micromobility. The ‘first and last mile’ distance traditionally covered by walking and cycling can be extended by other micromobility options, or made available to the less mobile. It diversifies public transport opportunities. Micromobility definitions, research and policies would therefore benefit from including multi-modal elements, particularly those that integrate with public transport. Similarly, multi-modal and public transport debates would benefit from closer consideration of micromobility.

2.7. Shared Mobility and Mobility as a Service

Some forms of micromobility are increasingly available as shared schemes, especially bicycles and e-scooters (docked and dockless). For this paper’s multidimensional approach to micromobility, equity questions (Dill & McNeil, 2021) from the shared mobility literature are especially relevant, for example, how to understand actual and potential users, who do or do not have access to these modes and why, and what conflicts over public space and parking emerge (Petzer et al., 2020). Mobility as a Service (MaaS), where (one or several) shared modes are made available via an app, including services such as wayfinding, booking, unlocking, etc. (Hensher & Mulley, 2020; Lyons et al., 2019) may or may not include micromobility. Unintended consequences of MaaS, such as further social exclusion and focus on monetary rather than social goals (Pangbourne et al., 2020) are also potentially relevant to micromobility discussions.

2.8. Smart Mobility

Many forms of micromobility include some digital/data element, especially shared schemes. The concept of smart mobility almost by definition involves the use of Information and Communication Technology (ICT) in mobility/transport, often in the context of smart cities. Emerging literature considers how to best approach the data elements of shared mobility (Fischer, 2020; Shaheen & Cohen, 2019; Transportation for America, 2020) and MaaS (Cottrill, 2020). This scholarship interrogates smart mobility’s knowledge claims and assesses how value is extracted and what issues arise around surveillance and privacy (Behrendt & Sheller, 2022; Petersen, 2019; Spinney & Lin, 2018). Studies of smart mobility sometimes draw on micromobility case studies (van Oers et al., 2020). Overall, discussion and governance of smart mobility is largely automobility focussed, with some consideration for public transport, but little regard for micromobility.

This critical discussion of eight micromobility-related debates has identified elements of each debate that are highly relevant to our socio-technical understanding of micromobility but have so far not been systematically integrated in the micromobility literature. The review of these debates has also identified potential for collaboration and synergy that can strengthen scholarship as well as policy debates around micromobility, beyond siloed perspectives.

3. Use and Definitions of the term Micromobility

While the micromobility-related concepts discussed above provide broader socio-technical context, this section shows specifically how the term ‘micromobility’ itself has been employed and defined in the academic literature and compares the two non-academic definitions that are frequently used.

3.1. Incidences and trends

We searched Scopus with the following keywords: (1) ‘micromobility’, (2) ‘e-scooters’, (3) ‘e-bike OR e-bicycle’, and ‘shared AND bicycle OR bike’, until the end of 2022[1]. Figure 1 shows the prevalence of these words in scientific papers in the (a) title, as well as in the (b) title, abstract and keywords.

The results show that the term ‘micromobility’ is mentioned 151 times in the title, and 510 times in the title, abstract, and keywords. A sharp rise in academic papers took place in recent years: from 2015 to 2019, 0 to 1 paper(s) with micromobility in the title were published annually, whilst in 2020 this rose to 12, in 2021 to 46, and in 2022 to 52. There is a similar increase for papers that used the term in their keywords and abstract. An earlier peak of the term (2004) was not transport related. Most papers during that period focussed on wireless (tele)communication.

A large increase in the number of published papers can also be observed for modes that are often associated with micromobility, such as e-scooters and e-bikes. The attention to e-bikes, shared bikes and e-scooters has so far prevailed over the specific term ‘micromobility’, and, in the case of e-bikes and shared bicycles has risen over a longer time, respectively, since about 2010 and 2015.

3.2. Use and definition of micromobility

Next, we focus on how the term ‘micromobility’ is used and defined in the scientific papers identified above. The search is limited to papers with micromobility in the title, rather than keywords or abstract, on the basis that such articles were likely to have a stronger focus on micromobility. Out of the 151 identified papers, this analysis only considers publications in journals, in English, and for the transport context, and excludes one publication that we could not access, resulting in 60 documents (see Table 1 & Table 2).[2] We then extracted data from the included studies regarding the studied location, whether a definition of Micromobility was provided, and if so, what the definition was. We also summarized the focus of the paper in terms of mode considered, the type of paper (e.g. review, empirical, case study) and the topic of the paper (see Table 2). Three authors were involved in the process and each screening step was conducted by at least two authors to reduce bias in screening and quality assessment. Table X gives the full bibliographical detail of the 60 papers included in the analysis.

Table 1 provides an overview of the definitions used in these 60 documents. Interestingly, more than half of the papers did not provide any clear definitions of micromobility. Those that explicitly offered a definition were often based on definitions by the International Transport Forum (ITF) and the Society of Automotive Engineers (SAE), but also sometimes based on Wikipedia, a website, or a provider of audit and assurance (Deloitte). Other papers operationalize the term but do not provide a clear definition. The absence of a broadly agreed definition of micromobility in the scientific literature has therefore resulted in variations of the use of the term and a subsequent lack of clarity and inconsistency in what is or is not included.

Several of the papers provide examples of micromobility, most often bicycles, e-bikes and e-scooters. Indeed, Table 2 shows that the majority of papers with micromobility in the title focus on at least one of these modes, including shared schemes. Although most papers consider more than one mode, the majority do not consider a wide range of modes. Shared forms of mobility have received more attention than privately owned transport modes. Interestingly, the growing literature on cargo-bikes does not appear under the label micromobility.

Most papers are empirical, but there are also seven reviews. The topics researched vary widely, ranging from traffic flows, distribution of stations or fleet, parking, safety, and equity, to travel behaviour (see Table 1 and Table 2).

3.3. Frequently referenced micromobility definitions by international societies and organizations

The definitions that the academic papers discussed above mostly draw on are from two institutions, the International Transport Forum (ITF) – 6 papers, and the Society of Automotive Engineers (SAE) – 6 papers. In the definition of the intergovernmental ITF, which is closely linked to the OECD, speed and weight are two key characteristics of micromobility. According to its ‘Safe Micromobility’ report, micromobility refers to “the use of vehicles with a mass of less than 350 kilogram (kg) and a design speed of 45 kilometers per hour (km/h) or less” that may be either “human-powered” or “electrically-assisted“ – although the report later states that fuel tanks are an option too (ITF, 2020, p. 14). The ITF notes that micromobility modes vary considerably in terms of design, stating that these vehicles are “polymorphic’’ and “cannot be defined by the number of wheels, nor by the riding position, which can be seated or standing’’ (ITF, 2020, p. 14-15). It distinguishes four types of micromobility vehicles, based on the two key defining characteristics, i.e. speed (“unpowered or powered up to 25 km/h (16 mph)” and “powered with a top speed between 25-45 km/h (16-28 mph)”) and mass (below “35 kg (77 lb)” and “35 – 350 kg (77 – 770 lb)”) (ITF, 2020, p. 16).

According to the Society of Automotive Engineers (2019)’s defining aspects are power type, weight, speed, and purpose. The “wheeled vehicles” should be under 227 kilograms (500lb) and have a speed below 48km/h (30mp/h). It is important to note that the SAE’s definition focuses solely on “powered micromobility”, either partially or fully powered, thus excluding exclusively human-powered vehicles. Moreover, its definition states that it is for “vehicles that are primarily designed for human transport and to be used on paved roadways and paths”. The SAE also has a classification system for describing vehicle types. Key characteristics include curb weight, vehicle width, maximum speed and power source, each with 2-4 options. Furthermore, the types of micromobility are distinguished according to centre column, seat, operable pedals, floorboard/foot pegs, and self-balancing (Society of Automotive Engineers, 2019).

The differences between the ITF and SAE definitions may appear small (see Table 3, section A). Still, they impact which modes are considered micromobility (see Table 3, Section B). This may in part explain the variety of definitions and inclusions of modes in the scientific literature. For example, many human-powered vehicles – including bicycles – would be included in micromobility according to ITF’s but not SAE’s definition. Excluding of human-powered vehicles has associated public health implications and is also Western-centric. SAE’s definition focuses solely on personal transport and excludes freight, while the ITF’s definition covers both. The ITF definition makes no explicit reference to wheelchairs but includes a mobility scooter in the visual. The SAE definition does not refer to mobility options used by those with mobility problems.

4. Dimensions and characteristics of micromobility

The analysis in section 3 has shown how the academic literature primarily uses vehicle examples and technical characteristics to define micromobility. Vehicle weight, range, speed and primary usage are deemed key. Yet, these features capture only part of what micromobility is. We argue for a socio-technical perspective (Geels, 2005) where vehicle technology is only one of several dimensions that should be considered, also driven by our mobilities approach (Sheller 2018).

This socio-technical mobilities perspective shaped the identification of the seven dimensions presented in this section. These are also derived from the analysis of micromobility related concepts (section 2) and from the use and definitions of the term (section 3). They are further informed by the authors’ expertise in the broader mobility and transport fields, including current micromobility scholarship.

Figure 2 gives an overview of the seven dimensions that we consider important for a socio-technical conceptualisation of micromobility – namely factors relating to the environment; human, social and cultural considerations; vehicle technology; infrastructure; economic; public health; and regulations and policy. These dimensions are discussed further below, building up the paper’s new definition of micromobility in section 5.

4.1. Environmental dimension

As transport emissions are rising globally and urgent calls are issued for their reduction (IPCC, 2022), being ‘micro’ in terms of energy use is key to micromobility’s significance. The environmental dimension underlines how micromobility offers a form of travel with the potential to decarbonize personal and freight transport. Most micromobility vehicles have relatively low energy requirements because they are small and light enough to be manoeuvred by one person, as discussed later, we consider this to be a key part of the definition. Walking is logically, therfore, also a form of micromobility, given that it has the lowest energy requirements of any form of transport. Recent studies estimate that large-scale take-up of LEVs (many of which are considered micromobilities) could lower personal transport-related CO2 emissions by 44% in Germany (Brost et al., 2022), while several studies assess the potential CO2 savings of shifting from car to e-bike at 12-50% (Cairns et al., 2017; McQueen et al., 2020; Philips et al., 2020). Partially or fully electrically and human-powered micromobility vehicles have zero greenhouse gas (GHG) emissions at the point of use. However, all-electric vehicles will incur upstream emissions from electricity generation – depending on how the electricity is generated, stored and delivered. There are also non-tailpipe emissions of toxic particulates from brake and tyre wear – but these are very small compared to those from car use.

GHG (expressed in carbon dioxide equivalent, CO2-eq) from vehicle manufacture, use and recycling and disposal also factor into the environmental impact metric and are generally lower for micromobility options than for cars (de Bortoli, 2021): Owning and using lighter, less material-intensive and much more energy efficient vehicles is less carbon intensive. Table 4 shows comparable figures for a range of vehicles, taken from a single source (Cazzola & Crist, 2020). Specifically, this table provides three key measures of the emissions:

• − Per vehicle emissions generated by vehicle and battery manufacture, assembly, delivery to point of purchase, and disposal.
• − Per vehicle emissions generated by the operational services involved in shared schemes
• − Emissions per passenger km directly generated by vehicle use.

Component figures from the source are given, rather than traditional lifecycle figures (for ‘all emissions’ per km or per passenger km travelled), since lifecycle calculations are strongly influenced by lifetime mileages. Since a paradigm shift to micromobility vehicles would arguably involve a shift to more localised living and working patterns, and/or combined use with public transport for longer journeys, to understand the scope for emission savings, it is therefore more meaningful to consider emissions separately in terms of ‘fixed’ emissions (from vehicle creation and disposal) and emissions that result from (different types of) use. Lifecycle figures suggest, for example, that using an ICE car compared to an e-bike would result in emissions that are only 6x greater^[4].

However, according to the data given in Table 4, the ‘fixed’ emissions associated with manufacturing, assembling, delivering, and disposing a private ICE car are 39 times greater than the same emissions associated with a private e-bike, and the per passenger.km emissions from use are 11 times greater^[5]. Other researchers suggest differences may be even more substantial. Consequently, a shift to micromobility has the scope to deliver considerably greater emissions savings than a consideration that lifecycle considerations might imply. Put another way, suppose someone only travels 2,000 km per year and plans to keep whatever vehicle they buy for 10 years: according to the Table 4 figures, for that type of travel, buying and using an e-bike would generate 0.4 tonnes of CO2-eq, whilst buying and using an e-car would generate 12.8 tonnes of CO2-eq. A key variable in these calculations is the expected lifetime of each micromobility vehicle, which– as discussed in the economic dimension below – varies across modes.

Micromobility also has implications for local air quality and noise levels. Human-powered and electric vehicles have substantial benefits in terms of local air quality, compared to conventional combustion vehicles. Often overlooked or framed as a safety hazard to pedestrians, micromobilities’ much lower noise pollution levels are also potentially a key benefit (Bakker, 2018). Electric bikes and e-scooters are generally not much louder than their acoustic versions. By contrast, electric cars are often not quieter than ICEs at higher speeds. The environmental dimension of our socio-technical understanding of micromobility is closely linked to the human, social and cultural elements of micromobility that are explored in the following sub-section.

4.2. Human, social and cultural dimension

People travel and move goods to meet their mobility needs, wants and musts. Micromobilities are one way to fulfil these needs. Examining the social dimension reveals who does or does not use micromobility, why, for what purpose, and how social and cultural contexts matter. It also includes geographical considerations: cities, regions and countries cultivate different cultures and combinations of micromobility modes, such as the Dutch high cycling share but no use of e-scooters, or the American low cycling share but strong e-scooter usage in large cities.

To date, certain micromobility modes have appealed more to some user groups or social groups than others (Melia & Bartle, 2021; Mitra & Hess, 2021). Age, gender and, socio-economic status all play a role (6-t for Voi, 2021). E-scooters have been popular with the younger generation, for example, while e-bikes (initially) attract older generations and the physically less able (Spencer et al., 2019). Age can be a criterion for access. For example, in the UK only those over 18 are allowed to use shared e-scooters, whilst e-bike use is limited to 14+. Such age restrictions should be up for debate particularly if the goal is to foster less car-dependent travel patterns from a young age. Shared micromobility services rely on a limited user base, and in places like Zurich, for instance, this base is comprised mainly of young, well-educated, affluent men (Reck & Axhausen, 2021). While there is a significant white/male/middle-class bias in the West, class biases also play a part in other countries and cultures (6-t for Voi, 2021; Hasan et al., 2019).

Households who do not own cars and individuals without access to a car because of their age or income, often have limited access to a full range of services and facilities. Micromobility arguably has the potential to reduce social exclusion (Tyler & Lucas, 2004), since access costs are typically lower, and vehicles are usable by a wider range of people. Though cheaper by comparison, access costs of micromobility still may be substantial, while shared services may often be in places where operators can maximise revenue rather than serving those where need is the greatest. This means that it is important to identify opportunities for promoting micromobility in areas that are vulnerable to car-related economic stress and that also have a high capability of replacing car km with micromobility. If supported appropriately, encouraging micromobility in such locations could contribute to relatively equitable carbon reduction (Philips et al., 2022).

The potential for micromobility is particularly high for the short and medium trips that people use most often like commuting, shopping, bringing children to school, and visiting friends or family (Abduljabbar et al., 2021). However, some types are more suitable for particular trips: e-cargo bikes and trikes are convenient for transporting cargo (shopping, children); e-scooters for shorter trips in towns and cities, and e-bikes for intra-urban and rural journeys (Philips et al., 2022) and for access to public transport (Azimi et al., 2021).

Most micromobility types do not require extensive skills, but many do require some basic skills (e.g. cycling) are required, and for safely riding an e-scooter, there are skills to be learnt and acquired (Department for Transport, 2022). All micromobility options could or should benefit from some form of training. Skills are often provided via informal settings such as in the family. Formal schemes (e.g. cycle or scooting training in schools) also exist – most often geared towards children but exclude adults or those not benefitting from a micromobility-supportive context (e.g. migrants). More training is needed for heavier e-cargo bikes, high speed e-scooters and e-bikes. Knowledge of traffic regulations is essential but not currently legally regulated in most cases. At the same time, training for motorists also needs to centrally include micromobility awareness and regulations, for example as part of licence exams.

This leads to the key issue of perceived safety and crash risks for micromobility. The current debate over-simplifies safety issues, casting some modes as safe and other as unsafe, and underplaying the role of automobility. In practice, it is not the rider but mostly the mode’s features (speed, safety features), the infrastructure, the traffic policy, and societal and cultural contexts that determine safety (Branion-Calles et al., 2019; Sanders et al., 2020). Micromobility’s actual - and perceived - safety varies widely between countries and cities but can often be a key barrier to uptake (ITF, 2020; Sanders et al., 2020; Sulikova & Brand, 2021).

4.3. Vehicle technological dimension

A vehicle, broadly defined as a machine that transports people or cargo (Halsey, 1979), often forms a key dimension of how micromobility is defined, including vehicle shape, number of wheels, size of wheels, number of seats, and centre of gravity. This is problematic. We argue that the use of a vehicle is not essential: walking is an important part of our understanding of micromobility. Walking may or may not include the pushing or pulling of a vehicle, such as a pushchair, a shopping trolley or a cart.

We therefore propose to include fully and partially powered as well as non-powered ‘micro’ vehicles that allow for a sit-down, recumbent and stand-up positions, with any number of wheels. Some vehicles can be used for carrying (cargo or people) loads or with physical impairment, often with 3- or 4-wheel design and lower, easy access (Cazzola & Crist, 2020). A maximum vehicle weight of 350kg, as per the ITF definition, makes sense in terms of ‘micro’ energy use and safety. In contrast, a car will usually weigh over 1000kg or more. In terms of vehicle speed, two characteristics are important: design speed (i.e. vehicle’s designed maximum speed) and, for electric vehicles, the max. assistance speed (i.e. the speed at which a motor ceases to assist or accelerate). Both can vary, depending on the vehicle type. Beyond the ITF and SAE definitions (see 3.3), speed restrictions also vary by country, particularly for e-bikes. According to UK, EU and Australian laws, e-bike assistance from the motor must cut out at 25km/h (15.5mph), whilst in the US it is 20mph (32km/h). It may be practical to consider 32 km/h the common threshold for many forms of partially- or fully powered micromobility, though with a sub-category that can achieve speeds of up to 45km/h (Cazzola & Crist, 2020). Human-powered micromobility can exceed these speeds (e.g. race cycling).

Another element is payload capacity. It refers to the amount of cargo and/or the number of passengers that a vehicle can carry in addition to the driver. For micro scooters, the extra payload is very limited. In contrast, e-cargo cycles are capable to transport 50-250 kg of cargo, and some even up to 500 kg) (Narayanan & Antoniou, 2021). Some types may add trailers to increase payload capacity.

Vehicle power, range and specific energy consumption are yet another criterion. ‘Motorisation’ may be specified on a continuum – ranging from non-motorized, to motor assistance, to fully motorised. Options include combustion engines and electric powertrains, even though vehicle development and deployment worldwide has recently focussed on fully electric propulsion (Cazzola & Crist, 2020).

Battery capacity (a measure of the available power, in watt-hours, Wh) is a key characteristic here, with associated costs and performance largely determining the vehicle’s price and suitability. The capacity of typical e-bike batteries range from 250 Wh (providing between 25 and 50 km in range) to 1,000 Wh, weighting 1.5-5 kg. E-scooter batteries have a capacity of about 500 Wh and weigh 4-5 kg (Kazmaier et al., 2020). Average e-cargo bikes have a battery capacity of around 400-500Wh, providing a range of up to 80 km (Narayanan & Antoniou, 2021), and their batteries are slightly heavier that e-bikes’ batteries. A typical e-bike charger would have a 5-amp (A) rating, charging a (small) battery to full capacity in an hour.

Regarding the motor, there are two systems of motor, namely hub-drive and mid-drive (Narayanan & Antoniou, 2021). While the former is meant for frequent riding on even roads with an occasional inclination, the latter is meant for frequent riding on hilly roads with an inclination of more than 3%. E-bikes and e-cargo bikes have an electric motor with around. 250 watts in much of Europe (Switzerland: max. 500 watts), with an average weight of 3-4 kg (Bosch, 2022b, 2022a). Average e-scooters feature motor power ranging between 200-500 watts, and higher-performance e-scooters offer a motor power of around 1200 watts (Aguila J, 2022).

As speed e-bikes (sometimes called speed-pedelecs) are more powerful and faster versions of standard e-bikes, the maximum motor output is about 4,000 watts (i.e. 16 times higher than e-bikes), giving assistance to pedalling up to the cut-ff speed of 45 kph. In the EU, speed e-bikes are classified as mopeds in the (cat. L1e-B) that require insurance and license plates. E-mopeds – sit-down scooters – typically have a top speed of 45 km/h, an average range of 43 km, and up to 4 kW for the motors (Schelte et al., 2021). In contrast, average e-bikes, e-cargo bikes, and e-scooters have an average speed of around 25km/h, with significantly higher speeds for higher-performance e-scooters.

‘Smart’ or connected vehicles equipped with either a one- or two-way flow of digital data are becoming more popular and are essential for shared services. Data-driven services include GPS tracking, geo-fencing (where the electric motor cuts out when outside a predefined geographical area), locking, route guidance, ticketing, and energy consumption monitoring. This is a fast-developing area (Behrendt, 2016; Nikolaeva et al., 2019). The detail of this vehicle-technological dimension of micromobility is important, but always needs to be understood as only one element of a socio-technical approach to micromobility.

4.4. Infrastructure

Micromobility requires appropriate infrastructure. Infrastructure should ideally be of high quality and safe for all user types, particularly for children and other vulnerable users. This often means purpose-built infrastructure like segregated lanes, tracks and junction designs. Since the 1920s, road space has been increasingly divided by vehicle types, e.g. cars, bikes, and pedestrians – to make way for automobility. Micromobility options may require rethinking whether this is most appropriate way. The quality of the road surface is of particular importance for small-wheeled vehicles. Reimaging roads’ design, speeds, and per-mode space allocation may be required to accommodate for potential larger volumes of micromobility. Geofencing may offer the potential to ensure that micromobility modes are speed limited (in specific areas/at specific times) to ensure compatibility between different travel modes. Low-speed/traffic zones (30 km/h) and play streets (where micromobility has priority and cars have to go at low speeds as ‘guests’) can reduce speed variability between modes or give priority to micromobility modes, both of which make it safer for people to use the slower modes. Furthermore, encouraging more localised patterns of living both facilitates, and is facilitated by, greater use of micromobility vehicles. Many examples and issues mentioned under the infrastructure dimension are equally about policies and regulations (see 4.7), highlighting the close connection between the dimensions.

As ‘micro’ suggests, micromobility vehicles typically have a lower spatial footprint than car travel – for both moving and parking. For moving, the ratio is about 1:4 for biking:car, 1:2 for e-cargo bikes:car (Ewert et al., 2020), 1:5.2 for e-scooters:car, and 1:6.5 for pedestrians:cars (ITF, 2021). For storage, the parking space required by one car can fit about 12 bikes, 15 e-scooters or 3 cargo-bikes.

Easy access to secure vehicle parking close to origins and destinations is key. It shapes how people choose their daily mobilities. Users, shared micromobility operators and local authorities fear vandalism and theft (Gössling, 2020). To encourage micromobility use, policy makers, transport operators, businesses and institutions need to make parking secure, easy and free or low cost, both in terms of quality and quantity, and with an eye to the great variety of micromobility modes. This is relevant both for public and private spaces and for shared and privately-owned modes. Providing secure and safe parking for micromobility around key destinations (shopping areas, railway stations, etc.) and at homes is central. It also facilitates multi-modal integration.

Micromobility is increasingly integrated with other forms of mobility, particularly public transport. Key issues are the ease and legality with which micromobility vehicles can be taken on board a train or bus, ease of access to the nearest bus or train station, integration and availability of parking at public transport hubs, and whether shared vehicles are integrated in terms of ticketing and journey routing. Overall, the infrastructure dimension of micromobility is embedded in the mobility systems and the built environment more widely. It is also closely linked to other systems, including energy and ICT.

4.5. Economic dimension

The economic dimension of micromobility has already been hinted in relation to the two main business models: individually owned or shared micromobility. For shared, the two main business models to date have been via docking stations or dockless parking/storage. Most shared systems involve ICT ‘enabled’ smart connectivity and payment methods. They require vans, trucks or e-cargo bikes to collect, charge, and reallocate e-vehicles, with implications for the carbon footprint (Cazzola & Crist, 2020).

The – private and shared – micromobility sector is rapidly evolving and have seen significant market growth over the last decade, with technologies, regulations, and business models changing quickly and unexpectedly (K. Heineke et al., 2020; ITF, 2021). After significant investment, the market saw several mergers, acquisitions and bankruptcies, also in response to post-Covid conditions and regulatory struggles (K. Heineke et al., 2020; Ratti & Auken, 2019). Still, some forecasts see the market grow from $48.11 billion in 2021 to $300 billion in 2030 (CBInsights, 2021; Edward, 2022; K. Heineke et al., 2020). Access costs to shared schemes vary, but often feature a time and/or distance component, while the costs of providing these schemes include re-location, maintenance and credit card fees (B. K. Heineke et al., 2019).

The technological maturity varies across micromobility options; cycles have been around for centuries so their maturity it is relatively high when compared with recently emerging modes like e-scooter and e-cargo bikes and trikes. The newer micromobility modes that are still evolving will benefit – in terms of cost, performance and sustainability impacts – from further innovation and development in all technical elements.

The cost of manufacturing, purchase – and maintenance – significantly varies according to the type, range and other technical specifications, production volume, location of production and distribution, construction materials, brand, accompanying software, and other factors. In addition to batteries, motors are key components in terms of costs.

‘Economic lifetime’ is often used in economic analyses of the costs and benefits of vehicles and mobility services. Micromobility features a wide range, from 3 months for some shared e-scooters (Schellong et al., 2019) to eight years for e-bikes (Buchert et al., 2015), and several decades for bicycles, though with figures generally rising over time.

Economic spillovers could include increased spending in local food, retail, entertainment, health, and fitness sectors, though eat-in restaurants might be negatively impacted by micromobility home deliveries (Kim & McCarthy, 2021; Rivlin & McCarthy, 2022). The economic dimension of micromobility is also closely related to public health, as tools such as the WHO’s Health Economic Assessment Tool for walking and cycling show.

4.6. Public health dimension

Most micromobility options require some form of physical activity above resting or car driving. This can have significant public health benefits. The level of physical activity needed depends on the vehicle type: walking and cycling are the most active, e-scooters require standing and some pushing off, and electric mopeds are the least active. Micromobility has been shown to improve both physical and mental health (Sanders et al., 2020; Sengül & Mostofi, 2021), even if electrically assisted (Castro et al., 2019). This being said, the main public health risks come from increased mortality/morbidity from crashes and exposure to air and noise pollution – particularly in mixed road traffic (Götschi et al., 2020; Maizlish et al., 2022). Policymakers should consider the large public health-related variation of different micromobility modes. Scholars and policymakers need to consider the synergies between micromobility and active mobility debates, including attention to conflicts and substitution between micromobility modes.

4.7. Regulations and Policy

The potential of micromobility is also shaped by regulations and policies: the final key dimension discussed in this section. The permitted locations for storage, parking, and use are key characteristics and vary by vehicle type and jurisdiction. For instance, e-bike weight, power, and speed restrictions vary by jurisdiction, typically ranging from 250 to 500 W maximum motor power and 25 to 40 km/h maximum speed with assistance (Bigazzi & Wong, 2020). As mentioned earlier, the UK allows only shared e-scooters to be used on public roads in trial areas, while private e-scooters are illegal on public roads or pavements. Micromobility delivery services – like e-cargo bikes – are often allowed to park in locations forbidden to conventional vans. Still, some private e-cargo bike users do not necessarily have full clarity on when and where they can park and secure their bikes. Parking policies for shared e-scooters have also seen wide variation (Brown, 2021). This policy area is dynamic and subject to change rapidly (both at the national and city level), but is clearly important.

Some micromobility modes are promoted and encouraged vis-a-vis other, less sustainable modes of transport. E-bikes and e-scooters, for instance, are often permitted to be used in clean air zones, city centre pedestrianized zones, and so on. Such policy may help uptake and encourage substitution of other motorized modes (car, bus, taxi/uber, etc.).

In some jurisdictions, riders/users are required to hold a license for public use for some categories of micromobility vehicles. This can be linked to the user’s age. Other jurisdictions require riders to carry safety equipment (e.g. helmet, lights) or stipulate third-party insurance as a requirement for use on public roads.

In sum, the seven dimensions of our socio-technical approach to micromobility discussed in this section demonstrated how much we can gain from attending to the practices, policies, cultures, and infrastructures that emerge around the use of these mobility options and shape their uptake. This significantly broadens the prevailing vehicle-focus in micromobility debates and scholarship.

5. New Definition of Micromobility

This section details our proposed new conceptualization of micromobility, drawing on the concepts discussed in section 2, the scholarship analysed in section 3, and the socio-technical dimensions outlined in section 4. For us, micromobility refers to a comprehensive and multi-dimensional concept that encompasses a diverse range of human-powered, partially motor-assisted, and fully powered mobility options primarily designed for short-distance travel.

In our definition, the term "micro" is relative and relates to energy demand, environmental impact, and roadspace utilization, compared to automobility. Micromobility can typically be manoeuvred by one human without motor assistance, at least for short distances. Micromobility includes various modes of transportation, such as walking, cycling, (speed) e-bikes, e-scooters, moped scooters, cargo bikes, rickshaws, wheelchairs, mobility scooters, (e)skateboards, and hoverboards. These modes typically operate at speeds not exceeding 32 km/h (or 45 km/h for faster options) and have a weight (generally significantly) below 350 kg, often offering some (public) health benefits from usage.

Our concept of micromobility extends beyond the physical modes of transportation and encompasses the surrounding ecosystem that enables and supports these mobility options. This includes practices, policies, cultures, and infrastructures that emerge around the use of these mobility options and shape their uptake, including interaction with other systems such as energy and ICT.

The definition emphasizes the movement of both people and cargo, reflecting the diverse purposes these mobility options serve. Micromobility trip lengths are typically less than 15 km with a daily distance travelled of less than 80 km. Figure 3 provides a visual summary of this new conceptualization of micromobility.

This novel definition of micromobility fills the gap in existing vehicle-centric definitions and offers a broader conceptual approach for future transport and mobility studies as well as policy development. A widely accepted and comprehensive definition of micromobility can facilitate the establishment of robust design standards, legislation, evaluation metrics, theorisation and methods, ultimately enhancing our understanding of and attention to this form of mobility.

6. Conclusion

This paper provides a socio-technical and multi-dimensional conceptualization of micromobility, filling a crucial gap in the existing literature. By considering the broader context and embedding micromobility within related discourses, such as active mobility, non-motorized transport, and light electric vehicles, this study has advanced our understanding of the term and its implications. Unlike previous research that primarily focused on empirical aspects, limited definitions, or the vehicle itself, our approach encompasses wider societal perspectives.

By adopting a multi-dimensional framework, this paper has highlighted the significance of incorporating human, social, and cultural considerations, as well as environmental, economic, public health, as well as regulatory and policy considerations, alongside infrastructure and vehicle technology dimensions. Our definition of micromobility encompasses a wide range of mobility options typically used for shorter trips and manoeuvrable by an individual without motor assistance, at least for short distances. These modes are characterized by their ‘micro’ attributes, including low energy demand, minimal environmental impact, and efficient use of road space relative to automobile-based transportation. This includes walking. Further elaboration of our definition can be found in section 5 of this paper.

We argue that embracing micromobility-inclusive or micromobility-focused approaches to sustainable mobility transitions presents a credible alternative to the current policy emphasis on electric cars. The latter has proven insufficient in achieving rapid carbon reduction targets (Brand et al., 2020), and lacks the principles of justice and inclusivity (Henderson, 2020) both in the Global North and South.

The potential of micromobility is further amplified when combined with public transport and urban planning. Therefore, future research should closely link micromobility debates with discussions about multi-modal transport (as discussed in section 2), Transit Oriented Development (Jain et al., 2020), Liveable Cities (Nieuwenhuijsen, 2020), and 15-minute cities (Moreno et al., 2021) to leverage and expand upon existing work on cycling and walking.

While this paper has made significant contributions, there are several limitations that offer opportunities for future academic work. These limitations include the lack of detailed historical perspectives, a predominantly Western-centric and ableist approach, limited integration of scholarship on walking, and a land-based perspective. Addressing these gaps would enhance the comprehensiveness and inclusivity of research on micromobility.

The socio-technical and multi-dimensional conceptualization of micromobility presented in this paper holds the potential to position micromobility as a central element in transition pathways, aligning with the Sustainable Development Goals (SDGs) (United Nations, 2015), and principles of mobility justice (Sheller, 2018a, 2018b). Moving forward, it is crucial to advocate for a world where micromobility is integral to the financing, strategizing, planning, and implementation of global, national, and local mobility and transport futures. This includes engaging international organizations such as the World Bank, World Health Organization and UN Environment Program, as well as integrating micromobility considerations into countries', regions’ and cities’ transport and climate change strategies and urban planning.