Urban electric bus: how to check whether a route is viable
The advertised range is not enough to make a decision. This documentary checklist helps assess the shift, bus configuration, charging and available power before a tender.
Key points
An urban route can be electrified if the vehicle offered, in its exact configuration, covers the actual shift and charging fits the available time and depot power. Before requesting bids, document the route, operations, passengers, masses, charging strategy and electrical infrastructure.
The short answer: validate the whole service, not a range figure
To determine whether an electric bus is suitable for an urban route, do not start with the advertised range in kilometres. You must check that the unit configured exactly for the contract can operate the full shift, that there is an adequate charging window, and that the depot can provide the required power when several vehicles charge at once.
The initial documentation must describe the service as it is actually operated, rather than as it is summarised on a map: journeys, kilometres per shift, layover time at termini, service duration, commercial speed, gradients and passenger demand. That information should then be converted into a consistent request for all bidders.
The precedent of an EMT Madrid tender is useful as a method, rather than as a value applicable to every network: it linked the requirement to 13 hours of service and an average commercial speed of 14 km/h, instead of requiring a distance alone. It also required range to be demonstrated with a vehicle identical to the one offered and allowed range and consumption tests to be carried out at its facilities.
Section references: Pliego técnico de EMT Madrid para autobuses eléctricos urbanos (2018) ↗
- A specification sheet for each route and each type of shift, including extra services and special allocations.
- Depot departure and arrival times, journeys, layover times and total kilometres per operating day.
- A route profile showing gradients and the points where demand is concentrated.
- Expected passenger numbers, the required interior layout and mandatory equipment.
- The charging strategy: overnight only, at the depot, at the terminus, or a combination.
- Available electrical power, power per charging point and the number of buses that will charge simultaneously.
From the route to the actual shift: build an operational route sheet
The first working document should be a sheet for each shift, not a daily average of kilometres. The same route can produce different operational results depending on departure time, assigned round trips, available layover time and when the bus returns to the depot. Separating those shifts prevents the battery and charging system from being sized around an average case that does not cover the demanding case.
Record mileage from depot departure to depot arrival. Include dead runs, positioning trips and any diversion or reinforcement that forms part of the planned service. Then record the total duration, time immobilised at the terminus and the actual return time. These data determine whether there is a real margin for opportunity charging or whether all energy must be restored overnight.
Commercial speed helps check consistency between the timetable and distance. It is also advisable to keep a gradient profile for the route and distinguish the sections repeated on every trip. The aim is not to find a universal consumption figure, but to provide the manufacturer with a verifiable operating pattern and ask it to state how it has assessed that configuration.
Passenger demand should be stated by time band and direction where available. The aim is to check that the proposal retains the capacity required for the service, especially if the choice of battery, doors, seats or auxiliary equipment changes the vehicle mass or interior layout.
Section references: Pliego técnico de EMT Madrid para autobuses eléctricos urbanos (2018) ↗ · MAN Lion’s City E: documentación técnica del fabricante ↗
- Prepare one sheet for the longest shift and another for the shift with the highest operational demand; they may not be the same.
- State start and end times, number of journeys, in-service kilometres and dead kilometres.
- Document layover time at termini, depot breaks and any time that could be used for charging.
- Attach a map or gradient profile and describe the expected occupancy conditions.
- Define the minimum passenger capacity and requirements for doors, seating and equipment before comparing vehicles.
Operational range: require comparable conditions and a test of the offered unit
A commercial range figure alone does not allow bids to be selected unless the conditions behind it are provided. The comparison must use the same configuration proposed for the route: unladen mass, battery type and capacity, climate control, number and position of doors, and seating layout. EMT Madrid explicitly included this criterion in its 2018 tender specifications.
Request a written declaration of the configuration assessed and avoid accepting a range attributed to another vehicle version. Configuration also matters for an operational reason: MAN indicates that adding battery packs increases range, while fitting fewer batteries can increase passenger capacity and reduce charging time. Range, capacity and charging must therefore be assessed together.
The operator may request additional information on expected outdoor temperature, use of climate control, traffic, topography and occupancy. This information can help compare the proposal against the route sheet.
In that EMT Madrid procedure, one documented way to verify the proposal was to include a range and consumption test of the offered vehicle, under agreed conditions and with the configuration recorded. If that method is adopted, it is advisable to define in advance which shift or route will be used, what information will be collected and what happens if the result fails to meet the service requirement.
Section references: Pliego técnico de EMT Madrid para autobuses eléctricos urbanos (2018) ↗ · MAN Lion’s City E: documentación técnica del fabricante ↗
- Request declared range, consumption and assessment conditions for the exact version offered.
- Require identification of the battery, climate control, doors, seats and vehicle mass used in the verification.
- You may request additional information on the temperature, traffic, gradients and occupancy expected in the operational sheet.
- If using the EMT Madrid procedure as a reference, provide for a range and consumption test before finally accepting the solution.
- Do not compare an isolated figure with a requirement expressed in service hours, journeys and availability.
Charging: the strategy changes the vehicle, timetable and depot
The question is not only where to place chargers, but when the energy needed for the next service will be recovered. If the route is designed for overnight depot charging only, the bus and the installation must cover the entire shift and restore the charge within the overnight window. In the cited EMT Madrid procedure, partial opportunity charging was not considered and full charging had to be completed within a maximum of six hours.
The alternative may be charging at the depot or by pantograph at the end of the route; both architectures are considered in the national guidance on low-emission zones. Opportunity charging should not be added to the design simply because a terminus exists: it must be demonstrated that layover time is compatible with it, that it does not affect regularity, and that the infrastructure will be available for the planned number of vehicles.
At the depot, ask the installation owner for the available power, its time restrictions, scope for expansion and the date by which any necessary work could be operational. AFIR highlights the relevance of private depots for overnight and destination charging of heavy-duty vehicles, and calls for infrastructure planning to be coordinated with grid planning.
Always distinguish station power from the power received by each bus. AFIR provides that a station's maximum power may be shared between different charging points. A proposal should therefore state how many vehicles will charge at once, the power allocated to each one in that situation and the planned charging schedule. The Bilbobus project linked to Metro Bilbao illustrates how available power and its time band can affect the design: it declared eight high-power points and 1 MW of infrastructure.
Section references: Pliego técnico de EMT Madrid para autobuses eléctricos urbanos (2018) ↗ · Reglamento (UE) 2023/1804 (AFIR) ↗ · Recarga inteligente de autobuses eléctricos urbanos con interconexión a la red eléctrica de Metro Bilbao ↗ · Directrices para la creación de zonas de bajas emisiones ↗
- Define whether charging will be overnight, opportunity-based or mixed before setting the energy requirement.
- Calculate the available window from the return of the last service to the departure of the first.
- Request a charging schedule for each vehicle, not only the chargers' nominal power.
- Check simultaneity: how many buses connect and what power each one receives.
- Request confirmation of available power, time constraints and any required depot works.
- If a pantograph is considered, validate the actual time at the terminus and its fit with layover time.
Capacity, masses and type approval: check that the bus can still provide the planned service
The battery must not be assessed separately from passenger capacity. Before awarding a contract, compare the offered interior layout with the minimum capacity required by the route: seated places, standing space, door positions and equipment. The choice of more or fewer batteries can simultaneously affect range, passenger capacity and charging time, according to MAN documentation.
Request the unladen mass in running order, the maximum authorised mass and axle loads for the final configuration. Applicable limits depend on the class, number of axles and specific configuration, so they must be checked in the current text of the General Vehicle Regulations before being included as a procurement requirement. Checking the total alone is not enough: the proposal must prove that axle load distribution fits the applicable limits.
Also include the type-approval documentation applicable to the specific unit and, where relevant, documentation on electrical safety under UN Regulation No. 100. This regulation lays down safety requirements for battery electric vehicles of categories M and N.
Common failures at this stage include requesting generic capacity without finalising the interior, accepting a mass that corresponds to another battery option, or reviewing total mass without requesting axle load distribution. The remedy is to turn each requirement into a document that can be required and link it to the offered unit.
Section references: Reglamento General de Vehículos: Real Decreto 2822/1998, texto consolidado ↗ · Reglamento n.º 100 de las Naciones Unidas: seguridad de vehículos eléctricos de batería ↗ · MAN Lion’s City E: documentación técnica del fabricante ↗
- Set a minimum passenger capacity and an interior layout compatible with operations.
- Request unladen mass, maximum authorised mass and axle loads for the final configuration, rather than for a catalogue version.
- Check the current text of the General Vehicle Regulations for the limits applicable to the class, number of axles and specific configuration.
- Request type-approval documentation applicable to the specific unit and, where relevant, documentation on electrical safety under UN Regulation No. 100.
- Reject comparisons that separate battery range from vehicle mass and passenger capacity.
Request table: comparable data before requesting bids
The tender or market consultation should require responses in the same structure. This prevents one proposal from highlighting range, another the charger's nominal power, and a third capacity, without any of them making it possible to verify the complete shift. The table works as a documentary checklist and as a basis for later clarifications.
In addition to submitting documents, suppliers should be asked to identify the assumptions used and any condition necessary for their solution to meet the service. If battery or charging alternatives are offered, each must have its own sheet for range, capacity, masses, times and power; data from different configurations must not be mixed.
| Area | Requested data or document | Practical check |
|---|---|---|
| Service | Shift sheet: times, journeys, in-service and dead kilometres, layover time and commercial speed | That the proposal covers the most demanding shift defined by the operator |
| Route and demand | Gradient profile, expected traffic conditions and occupancy | That the supplier states the conditions considered |
| Vehicle | Exact configuration: battery, unladen mass, climate control, doors, seats and interior layout | That range, capacity and masses correspond to the same unit |
| Energy performance | Declared range and consumption, method and assessment conditions | That figures obtained with different configurations or conditions are not compared |
| Validation | If the EMT Madrid procedure is adopted, a proposed range and consumption test of the offered vehicle | That the test is linked to the service and to previously defined criteria |
| Charging | Charging strategy, time window, charging points and schedule per vehicle | That charging fits between the end and start of each shift |
| Power | Station power, number of simultaneous connections and power per bus | That power sharing does not prevent charges from being completed |
| Depot and grid | Available power, time restrictions, required expansions and coordination with the grid | That the infrastructure can be ready for service commencement |
| Mass and capacity | Unladen mass, maximum authorised mass, axle load distribution and passenger capacity | That it meets the applicable limits for the class, number of axles and specific configuration, as well as service demand |
| Type approval | Type-approval documentation applicable to the specific unit and, where relevant, electrical safety documentation under UN Regulation No. 100 | That it corresponds to the offered configuration |
Section references: Pliego técnico de EMT Madrid para autobuses eléctricos urbanos (2018) ↗ · Reglamento (UE) 2023/1804 (AFIR) ↗ · Reglamento General de Vehículos: Real Decreto 2822/1998, texto consolidado ↗ · MAN Lion’s City E: documentación técnica del fabricante ↗
- Give all bidders the same route and shift sheet.
- Request a response for each specific configuration, including any battery alternative.
- Require the charging plan to state simultaneity and power per vehicle.
- If the EMT Madrid procedure is adopted, link final validation to a range and consumption test where the procedure permits it.
- Before awarding, check that the vehicle, charger, depot power and timetable describe a single compatible system.
Is it enough to require a minimum range in kilometres?
It is not the most useful criterion on its own. It is better to link the requirement to the complete shift, its hours, journeys, commercial speed and operating conditions, and to request the range for the exact configuration offered.
Does overnight charging remove the need to assess the depot?
No. You must check the actual charging window, available power, the number of buses connected simultaneously and the power each receives when the station shares power between charging points.
Why must axle loads be requested in addition to total mass?
Because both checks are necessary. Applicable limits depend on the class, number of axles and specific configuration, and they must be checked in the current text of the General Vehicle Regulations.
What should be compared if two bids include different batteries?
Each alternative must be submitted as a complete configuration: declared range and consumption, passenger capacity, interior layout, unladen mass, axle loads, charging time, required power and charging plan.
