Exploring battery-powered electric trains for Adelaide

Middleton Group worked alongside Ricardo Rail Australia to explore the feasibility of battery-powered electric trains in Adelaide.

The state government, keen to speed up its journey towards cleaner public transport, engaged Ricardo to explore zero-emissions options for trains on four rail lines in the city, with battery, full electrification and hydrogen power on the list.

Middleton Group’s rail team undertook traction power modelling for proof of concept and battery sizing for potential battery electric trains. Ricardo Project Lead Jorge Martin Gistau highlighted Middleton Group’s expertise in traction power modelling, which was key in identifying the most feasible solutions.

“By combining Ricardo’s global expertise in sustainable rail with Middleton Group’s capabilities,” says Jorge, “the partnership delivered insights and solutions greater than the sum of its parts, providing a clear pathway for Adelaide to move toward net zero rail.”

Middleton Group Senior Power Engineer Eric Bendtsen explains that as battery trains can be charged from the existing electrified rail network, they can run on lines without additional overhead wiring. This is especially valuable for Adelaide, where some rail lines currently use diesel trains and have no electrification infrastructure.

Battery electric trains, like electric and hybrid road vehicles, also recover energy from deceleration, particularly when they stop for stations, and this is stored in a battery for later use.

However, electrifying trains isn’t a case of just scaling up existing electric car-battery technology – there’s a lot more to it. For example, the battery train system needs to integrate into the existing traction power system, consider co-operation with the existing electric trains, and be able to cope with the unforeseeable, such as a train being blocked on a track for an extended period.

Eric says that three important numbers arose in the proof-of-concept work. One was the total energy that would be used by a battery on a full run of the line, which is required for accurate battery sizing. The second was the total energy that would be used across the battery train system in a two-hour period, and the third the total power draw at any one time, which helped determine that an extra substation would not be needed.

“This is really exciting work,” says Eric. “Battery-powered trains have been around for a while now but are not widespread in Australia and haven’t formed a large part of any metropolitan train system.”

Eric adds that South Australia often leads the way in finding new and novel solutions to providing services in an efficient and economical way. “This solution will allow the Adelaide metro rail system to move towards 100% renewable energy.”