Unlocking the full benefits of rail electrification

Virgin Hyperloop chief technology officer and co-founder Josh Giegel and director of passenger experience Sara Luchian

Primarily, there are huge energy and emission reductions to be had through regenerative braking energy recovery.

Every train journey involves a huge amount of braking and acceleration. When a conventional electric train decelerates, the motors act as generators and produce electricity. Most of the time, onboard loads and distant trains can only take a portion of this energy, and the surplus is wasted into resistors.

Wayside energy storage systems (ESS) enable operators to capture this braking energy and return it to the line to sustain the acceleration of other trains that transit on the same line section. The ability to harness the regenerative energy used in this cycle thousands of times a day offers the single largest opportunity to improve the energy efficiency of traction systems and reduce grid-based demand. It can reduce overall energy consumption by up to 30 percent.

These systems can also be used to manage voltage drops to keep trains running on schedule. Inherently, trains draw peaks of power during acceleration which can cause voltage drops and lead to performance problems causing costly operation delays. It can also result in large demand charges and peak penalties from the utility company, especially during rush hours.

Because it returns the energy during the acceleration, the ESS limits the power drawn from the grid and sustains the voltage level along the line. This reduces associated utility charges and can also be used, in some cases, as an alternative to avoid or defer potential capital investments for new traction substations and additional contracts with utility companies.

This approach also provides the assurance of critical power backup where, in the event of a power outage or instability from the utility network, operators can access stored energy to power the train to the next station where commuters can safely exit the train.

Another huge opportunity lies in the ability to return captured regenerative braking energy back into the grid.

An energy recovery system, for example, allows the surplus braking energy of an electric train vehicle to return to the AC mains – in compliance with supply grid standards. It also enables operators to negotiate a more competitive contract based on estimated self-generation.

Taking the industry from the traditional role of energy consumer to an energy producer, the result is a much more competitive railway operation.

Underscoring all of this is the increased role that digital technologies can play in delivering a more effective modern rail infrastructure that is fit for the future.

Inherently, there are a host of complex considerations for the modern rail operator; from maintaining 24/7 services and managing soaring demand while progressing modernisation programs, through to navigating extreme weather conditions and challenging price increases.

Digitisation could provide the answer, giving rail operators the deeper visibility needed to make better decisions in all areas of operational performance, while reducing energy and delivery costs.

A further opportunity lies in a dedicated distribution solutions offering, enabling networks to digitalise substations to increase efficiency, power supply quality requirements, and lifecycle management.

All of this is just the beginning. As rail electrification places a great focus on decarbonisation, leading manufactures will continue to raise the innovation stakes by delivering new physical and digital technologies to reduce energy use and environmental impact even further.

In the meantime, with benefits that include vast energy savings, emissions reductions and increased energy security, regenerative braking storage and recuperation solutions, along with digital tools, are key stops on the journey towards a more sustainable transport future.