Volvo Buses


How to make a smooth transition to electric mobility

As major cities across the world race to transition to net-zero, many of these cities have already embarked on re-structuring their public transport fleet to accomplish this common goal. In order to reach net-zero by 2050 within Australia as set out by the Paris agreement, a strong shift to electric technologies is required. So, how does one ensure a smooth transition to an electric bus system? And what are some of the biggest challenges and success factors? Find out below.


When is the right time for a city to make the transition to an electric bus system?

The answer to that question is really yesterday. To meet the Paris Agreement’s climate goals of completely fossil-free transport by 2050 to slow down global warming, it is urgent.


Actively transitioning fleets from the traditional diesel, mild hybrid, full hybrid and CNG buses to fully electric has been supported across several states of Australia with many planning to complete the overhaul by 2030. As recently as October 2021, the Australian Government released a roadmap to ensure the 2050 target is reached.


The approach to implementing electrified public transport differs a lot in various parts of the world. For example, China has today about 90 per cent of all electric buses in the world, mainly due to large subsidies for manufacturers and operators in recent years. This development has primarily been driven by the need to improve the air quality in large cities.


Improving air quality

In addition to the Paris Agreement’s ambition to minimise greenhouse gas emissions, every country has its own target for carbon dioxide emissions, as well as nitrogen oxides and particles. The transition to electrified vehicles will play a very important role here too.

According to the World Health Organization (WHO), air pollution has become the world’s single largest environmental health risk and it is the fourth highest cause of death among all health risks. Today, 90 per cent of the world’s population live in areas that do not meet the WHO’s minimum standards for air quality.


Reducing noise

Minimising traffic noise is another challenge that is high on the agenda for many cities, and where we can see requirements becoming increasingly stricter.

WHO recommends that noise levels along roads and sidewalks are not to exceed 53dB, where countless research In highly dense areas such as major cities recorded levels that well and truly exceeded this recommendation. Excessive noise can result in, among other things, an increased risk of disturbed sleep, cardiovascular disease and damaged hearing.

Both the negative health effects of noise and the construction of noise barriers can be costly. For cities, there is therefore much to be gained from reducing noise where it occurs. In city traffic, heavy vehicles with diesel or gas engines are among the dominant sources of noise.


Making public transport attractive

In addition to the fact that electrified public transport is necessary for achieving climate goals and reducing hazardous emissions and harmful noise, there are several other arguments in favour of electrified buses.

With growing populations and urbanisation, demands for functional and sustainable public transport increases. Traffic jams are already a very big challenge for cities around the world. For cities to be attractive in the future, they must be able to offer their residents efficient, sustainable, quiet and convenient transport options.

Electrified public transport also creates new and exciting opportunities for mobility and urban development. Without exhaust fumes and high noise levels, buses can operate in more areas and you can build in areas of cities that were previously unavailable. Public transport can take people closer to where they need to be, and you can even build bus stops indoors. All of this allows cities to become denser, but also more attractive for their inhabitants.


How long does it take to implement electric bus systems on a larger scale?

The conditions for implementing electrified bus systems on a larger scale vary hugely between cities. How long it takes depends on, among other things, local conditions for electrification and what the procurement procedure looks like. In most cases, you have to count on at least 18 months from the start of the process to when the buses can be put into service.

One of the biggest differences between the procurement of electric buses and conventional buses, is that there are many more stakeholders involved. In addition to the public transport authority (PTA), the bus operator and the manufacturers of the buses and charging infrastructure, the city municipality, the electricity providers and other relevant stakeholders, must also be involved at an early stage.

Careful planning and close cooperation between the various stakeholders are prerequisites for being able to take the step to large-scale implementation.

Another crucial issue is the availability of electricity. Regardless of which charging infrastructure a city chooses, electric buses place great demands on electricity capacity. It is therefore important to have an early dialogue with energy providers and the city about building permits and permits to rebuild and lay new cables to depots and charging stations.

Collaboration is key

The main stakeholders involved in the transition to electric public transport:

Public Transport Authority

Issues tenders.

Mayor office/Politicians

Set the high-level targets.

City municipality

Responsible for issues related to urban planning, building permits etcetera.

Energy provider

Ensures electricity capacity.

Public Transport Operator

Purchases system solution, manages bus operations.

Bus system provider

Provides electromobility system solutions (buses and charging infrastructure).

Several cities have conducted test projects with electric buses on a smaller scale and the lessons from those projects have been important when implementing larger electrified bus fleets. What we can see is that there is a lot of interest from cities in Australia to learn from each other and share knowledge.

At Volvo Buses we were very early in investing in electromobility. Thanks to our long and broad experience in delivering complete solutions to different cities, we are also ready to be a partner and sounding board for cities that are looking into the electrification of their city bus traffic in a sustainable way.

The energy required by electric buses

Securing enough energy capacity is crucial when implementing electric buses. During 12 years, the total energy usage for 100 electric buses (12 metre) is 97,200 MWh. That is equal to 400 private houses during the same period. But compared to conventional buses, the energy saving is huge.


How do you ensure an optimal charging infrastructure?

Different route lengths, topography, frequency, capacity and local rules and regulations mean that different e-mobility solutions are required for each city.

Ensuring an optimal charging infrastructure requires careful analysis and simulations of each individual route on which the electric buses will run. It is an extensive preparatory project that Volvo Buses as a system supplier does in close collaboration with the PTA, the operator, the energy suppliers and other stakeholders. These calculations then form the basis for our suggestions for buses, energy storage systems (batteries and supporting devices), charging strategy and charging infrastructure.


The right amount of on-board energy

Charging infrastructure is crucial for determining how many batteries and what capacity each bus needs. The batteries in an electric bus are still very expensive and resource-intensive to produce. It is therefore extremely important to make sure that the batteries are utilised in an optimal way to ensure the longest life-time possible.

When a battery is taken out of service from the bus, it still has capacity left. Instead of sending the battery for recycling, the battery can serve in second life applications, e.g. housing energy storage, UPS (uninterrupted power supply) and peak shaving. From a Life Cycle Analysis (LCA) perspective, the second life usage of batteries means that the “in-use” phase of the product lifecycle is significantly extended and thereby reduces the overall environmental footprint.

Open standards for charging equipment

A key question in the long-term transition to electrified public transport is having industry standards with open interfaces for charging infrastructure. All buses, regardless of brand, must be able to use the same charging stations. International organisations have been working on this topic for many years.

A key question in the long-term transition to electrified public transport is having industry standards for charging infrastructure.

An important bridge has been initiated where a one size fits all structure comes into play when charging electric vehicles. Within bus depots across Australia, you will see the same infrastructure spread throughout, this capability limits the need for adaptors and limits the need for electric buses to require separate treatment.


What's the true environmental impact of going electric?

Electrified public transport is hugely beneficial to the environment, primarily in terms of the reduction of greenhouse gas emissions, nitrogen oxides, particles and noise.

The overall environmental impact that electric buses have on society weighs far less than that seen of the common diesel bus today, reports suggest that battery electric buses successfully use anywhere between 32-46% less fossil fuels to successfully run than its diesel counterparts over a life cycle.  Along with this reduction in fossil fuels, Battery electric buses are also estimated to produce anywhere between 19-35% less C02 emissions than that seen by the traditional diesel bus. These massive savings across fossil fuels and C02 emissions mean that less pollution is evident within highly dense areas across the globe and less pollutant is escaping into the atmosphere.

An electric bus also consumes 80 per cent less energy than a diesel bus. The energy savings for the fleet of 145 Volvo 7900 Electric Articulated, which drive a total of 60,000 km per year at an average speed of 18 km/h, is 32,200 MWh per year. This corresponds to the yearly energy need for 1,600 private households.

How far can you go on the same amount of energy?

The calculation is based on tank-to-wheel energy consumption. Energy value of different types of fuel has been converted to kWh, where 4kg CNG = 5l diesel = 50 kWh electricity. Conventional diesel is used as a benchmark (100%) to compare results.

One question that often comes up in the debates around electric vehicles is how clean the electricity is from a CO2 point of view. Depending on whether the electricity is produced from renewable or fossil sources, the carbon footprint – from well to tank – can vary from as little as 10g to over 1,000g of CO2 per kWh.

In addition to the environmental benefits of electric buses, it is very important that all countries are involved in driving the development towards electrified transport. If we do not start the transition now, we will not achieve the climate goals that are necessary for reducing global warming.

Even though many countries globally still produce a relatively high proportion of their electricity from fossil sources, a positive trend is observed. A very large proportion of new Australian energy plants will produce renewable energy.

Electric buses also have a positive effect on a city’s noise levels.

Less noise emissions

With an electric bus, the noise level at take-off is reduced by 7dB. This means the perceived noise is cut by half compared with a conventional bus.

Electric buses also have a positive effect on a city’s noise levels. Each electric bus’s noise level is reduced by around 7dB from their diesel counterparts, ultimately halving its noise emissions.

A study on noise was carried out within the framework of the ElectriCity project in Gothenburg, which compared differences in the sound from electric buses, diesel buses and gas buses. The study showed large differences in noise levels at speeds of up to 40–50 km/h, with the electric buses being clearly quieter than the others.

The differences were greatest when it came to low-frequency noise, which is more difficult to mitigate with noise protection, facade materials and windows. According to recent studies, the indirect costs of noise pollution are substantial.


What are the most important success factors for the implementation of electric buses?

Political will

This is where it all begins. Making the transition to an electric bus system requires political will, vision and a political decision. It also requires a long-term system approach and knowledge of what electrification actually means, its effects, and the opportunities it creates.

Collaborative approach

Implementing an electrified bus system is completely different to buying diesel buses. Being successful requires close collaboration between various stakeholders and all partners must be involved in the process as early as possible. Otherwise, the risk is that the whole project fails because of a missing building permit or other authorization. At Volvo Buses, we have extensive experience in delivering complete solutions to cities around Europe. Good collaboration and a common vision, both in terms of environmental goals and creating an attractive city for residents, is something that everyone involved in large-scale implementations highlights as the most important success factors.

Thorough analysis

As a system supplier, we undertake meticulous analysis before every offer. Route distances, topography, climate, passenger numbers, traffic density, bus types, battery capacity – all of these factors affect which charging infrastructure is most optimal. Where and when will the buses be charged? Is it better to have three smaller depots rather than one large one? By undertaking analysis early on, we can ensure the city gets the best solution that suits them.

Ensure energy supply

To charge electric buses, large amounts of electricity are required and the power supply to depots and charging stations must be secured at an early stage. A close dialogue with the city’s electricity suppliers is therefore absolutely crucial.

Plan for implementation

Apart from a collaborative approach, a common plan for how the actual implementation is to take place is also required. This includes planning for the construction and rebuilding of depots, charging stations and stops, as well as applying for building permits and other authorizations. Again, it is important to ensure that all parties are involved early on in the process and that everyone is striving towards the same goal. For cities that already have some experience with electric buses, this is a simpler process. For those starting from scratch, more holistic planning will enable their electromobility journey to be successful