Digital Displacement offers a cost-effective and achievable route to decarbonise our rail sector

Digital Displacement offers a cost-effective and achievable route to decarbonise our rail sector

Reduced consumption, lower emissions

Whilst electrification has enabled the de-carbonisation of much of the UK’s rail sector, the high capital costs in electrifying new lines means that much of Britain (and the world’s) railways will continue to rely on diesel.

In 2010, Artemis completed a study with First ScotRail which showed that between 64 and 73 percent of a train’s energy is lost through braking and transmission.

In response to this, Artemis began a number of initiatives to demonstrate the significant benefits which digital hydraulics can bring to diesel powered rail vehicles.

In late 2017 we teamed up with rail operator ScotRail to test a standard commuter train fitted with a new type of digital hydraulic pump.

In this test, part-funded by the Rail Safety and Strategy Board (RSSB), we have replaced the standard hydraulic unit used to power each carriage’s cooling fans and generate electricity, which together use up around ten to 15 percent of the engine’s fuel.

Already the specially-equipped ScotRail class 170 Turbostar is being put through its paces on passenger routes including Glasgow-Edinburgh and Perth-Inverness.

We calculate this technology will save over 9,000 litres of diesel per carriage per year, and if adopted Scotland-wide across their fleet of class 170 trains, it would reduce ScotRail’s annual CO₂ emissions by more than four thousand tonnes, and fuel use by more than 1.5 million litres.

We believe this technology has the potential to be used in diesel trains across the UK and around the world.

In addition, we predict that if Digital Displacement technology were used throughout a train’s entire transmission – and not just the auxiliary systems – then overall fuel use could be cut by up to 30 percent

Faster acceleration, reduced consumption

We are also working with JCB and Chiltern Railways on a project funded by the RSSB to reduce fuel consumption and improve engine performance by combining highly efficient hydraulic transmission with on board energy storage in the form of hydraulic accumulators, which store energy during braking for reuse during acceleration.

The project will comprise a JCB diesel engine powering a standard Artemis E-dyn 96 Digital Displacement hydraulic pump.

Energy which is accumulated during braking can be released to supplement engine power, reducing journey times through enabling trains to leave stations more rapidly.

The technology could be applied to non-electrified rail routes where the case for future electrification is difficult to make. It also has the potential to provide benefits to rail users and train planners through reducing station dwell and journey times. The hybrid drive train can also be combined with an efficient downsized engine to reduce the emissions and fuel consumption of the fleet.

Artemis is testing the new solution on one of Chiltern Railways’ Mark 3 DVT vehicles. The test will take place over three months, starting in December 2017.