By Carlo Bianco, Business Development Director at Azienda Trasporti Milanesi (ATM)

The Business of Mobility is an Urban Mobility Company series highlighting some of the most successful new businesses in the mobility sector. Featuring a closer look at the way in which companies stand out, CEOs, Directors and other c-level executives elaborate on what it takes to turn a great idea into a great company.

ATM is the municipal transport company that runs Milan’s metro, buses, trams, traffic, ticketing, and bike-sharing systems. Milan recently committed to transforming its entire bus fleet of 1200 vehicles away from diesel. Currently, ATM has 124 e-buses and will increase that to 167 by the end of 2021. Here, Carlo explains some of the challenges.

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Our mayor – Beppe Sala – has committed to eliminating diesel buses on Milan’s streets by 2030. We’ve stopped buying diesel buses and our replacements are either electric or hybrid. But, developing a non-ICE fleet is far more complicated than simply replacing diesel buses with electric ones.

Range, capacity and space

Our standard e-bus takes 100 passengers, which is about 75% of the capacity of a diesel bus. The range of an e-bus is also less than a diesel bus – which can go for 300 kms. Another limitation of going electric is that e-buses take up more depot space. E-buses must be parked near their fuel source, and we find that in the same space we could park 100 diesel vehicles, we can only fit 70 e-buses.

Therefore, our biggest challenge is in retrofitting the infrastructure, or building new infrastructure, for non-ICE vehicles. We are fortunate that there is political will at all levels of government to transition to the green economy, and our project is attracting investment from the Italian state and the European Union as part of a green economy initiative.

Infrastructure solution

One of the main challenges of moving to electric is that we need more depot space closer to the city; we can’t have buses using 50 kms of range before they’ve even started their service. One of our solutions to the space problem – in a city where property is so expensive – is to build underground depots with a green area above. This initiative is not only about reducing emissions, it’s also about improving aspects such as air pollution and access to green space in our city.

To ensure we don’t have range problems, we are putting in fast-charging systems at all end-of-line terminals. Here buses will get a 10-minute boost to help them complete their mission before heading back to the depot for a full charge.

E-bus Maintenance

I’ve mentioned some of the disadvantages of e-buses, but there is one clear advantage: they’re easier and cheaper to maintain. Although we will need to reorganise our service plans and schedule of maintenance, we can at least plan on less downtime for our vehicles. Over the coming years our diesel mechanics will be reskilled in maintaining an electric fleet. And given that we’ll need fewer mechanics, some of them will move to other areas of the business.

What about autonomous?

Milan is Italy’s top city for public transport; half of all trips (pre-Covid) taken by our 3.2 million inhabitants are by public transport. We’re also a leader in automated metro systems, something I’ve dedicated much of my career to. For the past ten years our metro has had 50 kms and 50 stations managed by automation. We’ve leveraged some of that expertise to develop TECH BUS, a trolleybus running along one of Milan’s major circular routes (line 90/91). The project has been developed by the Joint Research Lab involving ATM along with various private and public partners including IBM, Vodafone, and the Politecnico di Milano. With embedded sensors and semi-autonomous technology, the bus can communicate with traffic lights and road infrastructure to create more seamless movement, improve road safety, and bring us one step closer to an autonomous system. You can read more about that here.

Is hydrogen the way to go?

Since 2013, ATM has done much pioneering work in hydrogen with test plans and experimentation. Hydrogen has its advantages: decent range, quick fill-up, and no need to carry heavy batteries in the vehicle. We have a small plant producing hydrogen (the first such plant in Italy), which fuels a few buses. It’s a technology that we’ve been testing for a long time, but for now it seems that globally, hydrogen fuel-cell development is still well behind battery-charged vehicles, partially due to the high operational cost compared to other alternatives.

Is it about reducing pollution or carbon?

Milan is one of the most polluted cities in Europe, with little wind to sweep away industrial and transport fumes. It’s imperative that we reduce diesel emissions, so the immediate goal of this project is therefore to reduce city street emissions to zero. Today 70% of our vehicle-kms are already running on green electricity (trams, trolley-buses and metro). But ATM is also committed to carbon-free energy generally, and that’s why we use PV panels at our offices and are charging buses with electricity from renewable sources, saving tens of thousands of tonnes in carbon emissions. However, we’ve needed to stay realistic about what’s possible. We have a large, complex service to run and if we have to power some buses with natural gas, then we will consider that as an option. Our immediate goal is to keep our world-class service running and meeting the needs of citizens without polluting city air. And of course, the second part is to contribute to the burgeoning green economy.

Remaining Flexible

We know that our project relies on boosting electricity infrastructure: 1200 buses charging up at the same time will add considerable load to our grid. That’s why we’re staying flexible with our solutions. The big problems to solve for right now regarding e-buses are capacity, weight of batteries, and recharging times. New technology could disrupt current solutions, and therefore ATM is keeping its options open in terms of the ideal supplier for our needs. We’re also committed to staying flexible around the ideal technological solution that allows us to stay on the leading edge of technology. We’ll use this to inspire us in building an emissions-free bus system that serves one of the world’s leading cities.