Posted 5th August 2008 | No Comments

Easing up on throttle saves two million litres of diesel a year

Above: Map showing the routes on which drivers can cut back power. Home Page: A Class 185 bound for Manchester Piccadilly heads through Pennine hill country.

FUEL consumption by Class 185 diesel trains operated by First TransPennine Express has been cut by 1.8 million litres a year, thanks to an ‘eco-initiative’ carried out jointly with Siemens, the trains’ manufacturer.

The fuel savings – equal to a seven per cent improvement across the 51-strong fleet of three-car trains, and a saving of 12 tonnes of carbon dioxide emissions every day – have been achieved by selective shutting down of diesel engines and by new driving

Further savings are expected to be made soon when engine management will be controlled automatically ac-cording to a train’s location, as determined by satellite.
When FirstGroup specified new trains for the Trans-Pennine franchise, it called for one 560-kilowatt diesel engine per vehicle to provide sufficient power for climbing steep gradients, especially between Leeds and Manchester.

The Class 185 trains – a diesel-powered version of the Desiro electric multiple unit – have proved the most reliable DMUs on the British network. But they have also been criticised for their weight, fuel consumption and carbon emissions.

Now, by reducing the number of engines idling while trains are in stations and depots, shutting down one to two engines when descending gradients and advising drivers when to shut off power during acceleration, fuel use and carbon emissions have been cut.

The internal electrically-powered systems in the Desiros continue to function because of the electrical cross-feeds incorporated in the trains’ original design.

Siemens says it made use of the trains’ in-built computerised diagnostics to analyse performance and learn what could be done to save fuel and cut carbon emissions. The resulting techniques were developed in consultation with First TPE’s drivers and driver managers, and then incorporated in a new advice manual, said Hans Benker, of Siemens, speaking at the London conference.

Amongst the new fuel and carbon saving measures are:
- If the driver’s key is inserted in the control desk and the engines have been idling for six minutes, one engine in each three-car unit is shut down, but air-conditioning maintained.
- If the driver’s key is not inserted, two engines are shut down after only one minute’s idling and the air-conditioning turned off.
- When running empty to depots, each three-car set uses only one diesel engine.
- While descending gradients, one, sometimes two, engines are shut down by the driver according to advice in the driving manual.

Hans Benker said that engine-idling over five minutes has been reduced by an average of 90 minutes per day per train, and total engine hours cut by an average of two hours per day.  As a result, Siemens now predicts a 15 per cent extension in the life of the Class 185 diesel engines.

First TPE drivers are provided with feedback on an in-cab screen at the end of each journey, telling them how many litres of fuel have been consumed on the trip.

Further savings are expected to follow soon when GPS co-ordinates are used to automatically turn off one engine in each three-car set while running on the flatter stretches of track east and west of the Pennines.

Meanwhile, Siemens and First TPE are still trying to find a simple way of using GPS to manage the number of engines in operation over the Pennine gradients, depending on whether the train is going up or down hill.

 Hans Benker said the Class 185 ‘eco initiative’ had not involved any complicated contractual arrangements. The manufacturer had developed the project jointly with First TransPennine Express and both agreed that any benefits would be shared 50:50 between the companies.

A FTPE spokesman said the company used 24.8 mil-lion litres of fuel and hopes to cut consumption by 2.5 million litres through further efficiencies.

- The fuel saved would run more than 1,000 family saloon cars for 12 months.