Globally, many countries and corporations have set targets to reduce their carbon emissions. Buses which primarily run on diesel are a large contributor to carbon emissions and are a low hanging fruit for achieving carbon reduction targets. In addition to their contribution to global pollutants, diesel powered buses are a significant contributor to local pollutants that directly affect the health and well being of the local community. An EV fleet of buses would reduce carbon emissions, eliminate tail-pipe emissions, and reduce noise. According to research, each Electric bus can save the planet from 990 tonnes of CO2, 375kg of NOx, and ½ million litres of fuel consumption.
The electric bus market size is projected to grow from 81 thousand units in 2021 to reach 704 thousand units by 2027, at a CAGR of 43.1%. Demand for new buses and coaches in just the European Union was 18.1% higher than last year, with 1,863 units sold in total. Under the new rules, the EU is bound to include a quarter of EV buses in their total buses purchased by 2025. The ratio will increase to one-third from 2030. Many other cities are embracing similar declarations for fossil-free streets with buses being the major contributor in the spotlight.
Perks of Fleet Electrification
Bus fleets are heavily utilised, usually have fixed timetables, and have regular overnight garaging locations. These three characteristics of buses make transitioning to an EV fleet relatively easy. In many regions, trials have already shown that electric buses have low whole of life costs as a result of lower maintenance and refueling costs. Additionally, buses in an EV fleet offer opportunities for grid integration by connecting solar depots to the grid through their batteries.
Considerations of the Electric Bus Fleet
When considering EV fleets, bus operators will need to consider:
- Emissions reductions and delivery of renewable energy to ensure zero emissions
- Electricity capacity of sites
- New depot configurations
- Battery range of the fleet vehicles
- Impact of topography and climate on battery efficiency and range
- Bus route optimisation
- Charging management
- Energy generation (such as onsite batteries and solar power)
- Driver behaviour
- The total cost of ownership based on balancing higher upfront costs with lower operating costs
Total Cost of Ownership
The total cost of ownership is a pivotal element of consideration for a commercial EV fleet. TCO parity across different timelines is helpful for bus fleet operators to make wise economic choices.
Similar to other new technologies, electric buses also present some challenges for bus operators. The upfront purchase price of an electric bus is higher than diesel alternatives. The weight of a battery in an electric bus is higher than a tank of petrol and diesel, increasing the vehicle’s tare weight and reducing its payload capacity. EV Fleet operators eyeing at including EVs in their fleet might need more integrated costing models.
Here’s a list of the most relevant cost components for the total cost of ownership calculation. The values can be combined with the following cost components in order to work out a unified total cost.
- Cost of purchasing the vehicle excluding the residual sale value
- Financing cost beyond retail price – cost of interest payments
- Fuelling – Proportional to distance travelled, the efficiency of a vehicle, and cost of the fuel/cost of electricity
- Charging infrastructure and batteries for EV charging
- Insurance – Typical costs associated with insurance cover and vehicle replacement or repair
- Maintenance & repair – inspections, regular maintenance, scheduled part replacement, and unscheduled replacement of parts
- Taxes & fees – taxes paid on time of purchase, recurring annual costs, registration fees, parking, and tolls
- Labor – typical wages and benefits for drivers, and costs for the time of charging and fuelling
Charging Electric Bus Fleet Vehicles
The electrification of buses will require the installation of electric vehicle charging infrastructure. This may also include electrical capacity upgrades for charger locations.
There are currently two models of EV bus charging being utilised globally:
|Depot based Charging |
Buses are charged overnight using on-site electric vehicle charging infrastructure
|Lower upfront capital cost||Potential grid limitations may require an upgrade|
|Allows for off-peak charging||New depot and charging management|
|Located on the pre-owned property||Longer refuelling time|
|On Route Charging|
Buses are charged via fast chargers along the bus route
|Smaller battery packs mean a higher passenger count||More expensive and may require leasing/purchasing land|
|Greater flexibility in bus operations||Requires fast charging and may incur higher energy costs with DC grid integration|
|Can compete for more than one route with a rest period|
Might require changes to contracting and performance management terms
Note: a combined model approach may be appropriate
Challenges for Bus Fleet Operators
- Capital cost: the upfront purchase price of an electric bus is higher than petrol and diesel alternatives.
- Passenger capacity: Bus passenger capacity is limited by heavy vehicle weight restrictions.
- Upskilling: An electric bus will require new driver behaviour, procurement models, maintenance requirements, and refuelling operations.
- Charging infrastructure investment and management: Additional assets investment is required to refuel electric buses via electric vehicle charging stations. This may also include electrical capacity upgrades for charger locations.
With the rapid increase in electric buses around the globe, performance data is starting to emerge. Many municipalities are also conducting their own trials to work out how particular buses will perform on their routes. This is giving decision-makers more clarity on the stated versus actual energy efficiency (kWh/km) of electric buses. Factors such as ambient conditions, topography, and bus characteristics have significant effects on the real performance of an electric bus.
Efficiency plays a key part in sizing a depot’s charging infrastructure, electrical upgrades, and potential upstream infrastructure costs. It affects how long buses need to charge for, the coincidence of peak demand from multiple chargers, and the ability of buses to meet their charging needs in line with their schedule.
The International Energy Agency’s Global EV Outlook reveals interesting insights about the EV market, especially focusing on regions such as Helsinki (Finland), Shenzhen (China), Kolkata (India), and Santiago de Chile (Chile). Electric fleets face context-specific challenges related to network size, ridership, degree of sector privatisation, and the availability of funding streams other than fare revenues.
Evenergi Consulting for e-Buses
Evenergi has developed a solution that helps bus operators to seize the opportunities and manage the risks of an eMobility future. The solution provides the development of economic and technical models to support the migration to electric buses, using Evenergi’s model to emulate your e-bus fleet network to assess the impact of EV charging on-peak electrical demand, support the selection of potential bus suppliers, help understand the bus market dynamics and support grant opportunities and submissions.
Find out more about how Evenergi can help here.