Electrification is the way forward
"The article “Clearing the line” by Dave Shirres was a timely restatement of what most of us who have worked in the industry know, that further electrification is the only way for rail to be less carbon-hungry and more energy efficient (Professional Engineering No 5, 2019).
Hydrogen power and bi-mode trains have their own constraints and, due to the mass and energy-density issues that Shirres highlights, can never be the best route to de-carbonisation.
However, if we are to electrify, while also improving overall rail network performance to make train travel more attractive and increase market share, then we have a lot of work to do to make the electrification system more reliable and resilient.
The recent national grid outage had a disproportionate effect on the rail network due to a weakness in the restart capability of a particular train fleet. Electrification infrastructure failures are not uncommon, and when they occur are highly disruptive, with routes often blocked for hours. Even cutting-in a stand-by on-train diesel generator is of little help if damaged overhead line equipment is strewn across the tracks or wrapped round the locomotive!
Some topics that need addressing include renewal or refurbishment of older overhead line equipment, more rigorous maintenance of alignment and tensioning, elimination as far as possible of head-span overhead line systems where damage to the wiring on one line invariably closes all the other tracks, vegetation management to reduce the number of trees falling onto overhead equipment, and wiring of more diversionary routes.
Work is also needed on feeder-station capacity – there are routes where diesels are welcomed by Network Rail because there isn’t the power supply capacity to sustain a full electric service. We must also mitigate against climate change consequences of intensified wind and rain impact on equipment.
Lastly there is the need to promote common understanding between electrification and rolling-stock engineers – in the British Rail era this all came under one technical department whereas in the recent past new train introductions have been delayed by wrangles over the train/infrastructure current collection interface at the contact wire.
Only when we have confidence in a highly robust electrification network, embracing a systems integration approach with the trains themselves, can we with confidence demand the further electrification that is indeed the best way forward for the passengers and the environment."
Phillip Hinde, East Sussex
More salt please
"I was prompted to write as a result of the recent cooling tower demolition at Didcot Power Station and by a newspaper article, which queried who was going to pay for the costs of uprating the power distribution system resulting from increasing electrical demand.
It must make more sense to have a distributed system of generation rather than a small number of very large and vulnerable generating plants.
Reusing existing generation sites, which are already connected to the national grid, and replacing the coal-fired equipment with for example the Moltex Stable Salt Reactor system with all its known benefits has to be the way forward. This option provides a robust arrangement from a risk point of view with better diversity and avoids the huge cost of increasing transmission capacity from a small number of high-output, expensive stations.
Have we missed a trick or am I just having a bad day?"
Marcus Field-Rayner, Bury St Edmunds, Suffolk
Rejigged rigs
"How opinions change! In the mid-1980s I was a member of the then Aberdeen Panel, and we put on a lecture about disposing of old offshore installations at the college in Fraserburgh, Aberdeenshire (“New life for old rigs,” Professional Engineering No 6, 2019).
There was a retired trawler skipper in the audience, who was all in favour of breaking up the rigs and spreading them across the seabed. First, he argued that the wreckage would provide shelter for young fish and become a nursery bed. Secondly, he argued that nobody would fish the area for fear of snagging their nets and losing them. He argued that this would allow fish to develop for his sons and grandsons to catch (his words).
Apparently, it was impossible to insure the nets, but more importantly there have been incidents since where trawlers have been dragged under by snagged nets.
Ten years later we had all the controversy over the disposal of the Brent Spar, because of worries about pollution. Come forward another 20 years and it is now respectable to use redundant installations as artificial reefs.
The old trawler skipper was right."
John Torrance, Flookburgh, Cumbria
Social engineering
"At my recent NHS information governance training session, the leader was speaking about criminals ‘phishing’ for information by posing as service providers from telephone and pension companies.
He coined an expression I had not heard before, ‘social engineer,’ to describe these criminals. I nearly fell off my chair!
It’s one thing to be grouped with a car mechanic on Coronation Street but now we are grouped with con merchants, crooks, embezzlers and fraudsters!
Unbelievable!"
Jim Marr, Brigg, Lincolnshire
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Content published by Professional Engineering does not necessarily represent the views of the Institution of Mechanical Engineers.