What's the deal with electric?

Schuhart · 21-07-2006 7:01pm #1

I'm just trying to get some appreciation of what the key benefits of electrifying the Maynooth line (well, any line, but that's the one I travel on).

I can appreciate there are possible environmental benefits - assuming the electricity is generated by something kinder than a diesel locomotive.

But is there any other benefit? Does it speed up trains significantly, or are they cheaper to run?

Any information - or links to relevant information - would be of interest.

bryanw · 21-07-2006 7:24pm

Acceleration is better on electric, so the train should be faster between frequent stops.

Victor · 21-07-2006 8:51pm

The fuel consumption is give or take, but central generation is generally cleaner.

Electric is generally quieter.

MarkoP11 · 21-07-2006 9:02pm

You do get much better acceleration even compared to a diesel powered train with similar weight and power, large diesel engines take several seconds to reach full power even then absolute full power is only available at a failure narrow rev window, modern electric trains you get 100% power from the start and sustained all the way to nearly top speed. You are looking at ballpark 34 seconds to 60mph on a DART best the 29000 railcars manage is in the 45 seconds ballpark

Its so much quieter even at full power on an electric train, the original DART was a little noisy, new technology means its extremely quiet

Running costs are lower, fewer moving parts less to go wrong, DART reliability even at testing phase was hitting 250,000 km per failure for periods of time

Under braking the motors are used as generators and power is sent back into the overhead system, 12% saving from that is an accepted number, saves acrea on brake disk as well

There is a seriouly heavy IEE paper about the DART onlne unless you are into circuit diagrams it might not be for you

dam099 · 21-07-2006 9:09pm

Isn't electric also necessary so that the trains on that line can use the interconnector tunnel once it's built?

BrianD · 22-07-2006 2:27am

I understand that when Maynooth to Clonsilla was upgraded a few years ago, they made allowances for installing overhead gantries at a later stage. In reality, the Maynooth line should have been Dart-ified 20 years ago. It's a mystery (well probably not) why only one of the available commuter lines in Dublin was electrified.

Schuhart · 22-07-2006 10:36am

Lots of useful information there - certainly enough to give me an idea of what I should google for.

MarkoP11 wrote:

There is a seriouly heavy IEE paper about the DART onlne unless you are into circuit diagrams it might not be for you

I'll give anything a look. I suppose the core of my interest is stuff about how the cost of electrification relates to the benefits - for the sake of argument, if electrification knocks 10 minutes off journey times, how much does it cost to achieve that or estimates/assessments of the savings in energy costs on other lines. That sort of thing. But I'm still interested in anything that relates to the general topic.

paulm17781 · 22-07-2006 11:27am

dam099 wrote:

Isn't electric also necessary so that the trains on that line can use the interconnector tunnel once it's built?

Maynooth will run to Bray. They won't actually use the interconnector.

bk · 22-07-2006 1:25pm

paulm17781 wrote:

Maynooth will run to Bray. They won't actually use the interconnector.

Yes Maynooth will continue to run to Connolly and on out to Bray.

However he is right about the Kildare line, it will run through the interconnector and will require to be electric.

spacetweek · 22-07-2006 1:33pm

dam099 wrote:

Isn't electric also necessary so that the trains on that line can use the interconnector tunnel once it's built?

You're thinking of Kildare, but in any case, the major reason is better acceleration and less noise. The tunnel has little to do with it - I think some diesel locos will run through the Interconnector anyway , can someone confirm?

MarkoP11 · 22-07-2006 1:47pm

No diesel powered trains will operate through the tunnel. The stiff gradients required at the Sepncer Dock end would rule out locomotive haul without question

The economists went as far as saying Bray Maynooth should be diesel operated and that no electrification was needed as a result

enterprise · 22-07-2006 3:16pm

Schuhart wrote:

I'm just trying to get some appreciation of what the key benefits of electrifying the Maynooth line (well, any line, but that's the one I travel on).

I can appreciate there are possible environmental benefits - assuming the electricity is generated by something kinder than a diesel locomotive.

But is there any other benefit? Does it speed up trains significantly, or are they cheaper to run?

Any information - or links to relevant information - would be of interest.

Take a trip on a E.M.U. aka the DART for yourself to see!

Schuhart · 22-07-2006 4:29pm

enterprise wrote:

Take a trip on a E.M.U. aka the DART for yourself to see!

With DART I'm not sure the difference in acceleration is so striking to make the benefit immediately obvious from the punter point of view (at least to me). I've used the DART now and again and, to be honest, I don't feel like I'm stepping into the dark ages when I transfer back on to a diesel railcar on the Maynooth line. I suppose that's really what raised the question in my mind.

I utterly accept that when you sit down with a stopwatch and a piece of paper you could find the accumulated benefits of the extra acceleration - presumably increasing capacity per hour in addition to saved commuting time - make the investment worthwhile. I'd just like to get some grip on what the yielded benefits are.

Victor · 22-07-2006 8:43pm

A loco hauled train loses about 3 minutes for each stop. With DART, after three minutes you've been through two stops and travelled the distance.

dowlingm · 24-07-2006 5:34pm

It's not as if the displaced DMUs will go to waste anyway if Galway-Athlone, Midleton/Cobh-Mallow and Limerick-Nenagh/Limerick-Ennis suburban all improve, plus there's Ballina and Navan-Clonsilla (and Navan-Drogheda

).

Darando · 24-07-2006 10:47pm

When it comes to looking at train systems in Europe they have a high proportion of electrification.

Im guessing this has something to do with Irish railway network formerly falling under British control.

Once the steam engines went the british choose diesel trains, whereas the europeans went for electric.

So the big question is: Who choose the right method? Uk or Europe?

Victor · 24-07-2006 11:24pm

I'm not sure if its that simple. The UK also has electric and the continent has diesel. It tends to be more that electric is more expensive and is only justifiable on busier routes.

MarkoP11 · 24-07-2006 11:39pm

Darando wrote:

When it comes to looking at train systems in Europe they have a high proportion of electrification.

Im guessing this has something to do with Irish railway network formerly falling under British control.

Given the Irish network was independent since 1922, long before the development of practical diesel or electric trains for intercity use, the fact we were broke was the issue

Darando wrote:

Once the steam engines went the british choose diesel trains, whereas the europeans went for electric.

So the big question is: Who choose the right method? Uk or Europe?

Everyone chose the best option for them at the time

Ireland was in fact well ahead of the UK, CIE was the first European rail company to ditch steam in 1963, NIR were plugging away with steam into the early 1970's

Traffic levels in Ireland are tiny no justification for electrification, the busiest mixed traffic railway in Europe is the West Coast line in the UK which was the first long distance UK line to be electrified

Mainland europe went electric since they had a clean start after WW2 they needed a rebuild from the ground up, they had heavy traffic. In comparision the business case for the DART project was marginal, CIE made it work since computer technology massively reduced staff requirements

Darando · 25-07-2006 12:08am

Thanks for clearing that one up. Always wondered what the correct answer was!

So what are the benefits of electric over diesel then? (in our case or europes case for instance?)

Victor · 25-07-2006 12:34am

Darando wrote:

So what are the benefits of electric over diesel then? (in our case or europes case for instance?)

Read the first few posts on this thread.

dowlingm · 25-07-2006 9:08pm

It's easy to have lots of electric rail like France when you have a huge number of nuclear plants and interconnection with other countries to ensure supply. Ireland is only now getting going on an interconnector to Wales.

Schuhart · 25-07-2006 10:18pm

I have some products of a lost evening Googling that might be of interest.

I found an article here that’s reasonably interesting., although its about North America. The key point for me is that, in the specific case he cites, electric journey time was 75 minutes where diesel would take 90 on the same route. The result was 7 diesel trainsets and crews could be replaced by 6 electrically propelled ones with 20 percent more revenue from the faster trip.

Electrification of Kildare/Maynooth/Drogheda seems to be costed at around €300 million. Using the AA route planner, Dublin to Kildare is 35 miles, Drogheda is 31 miles and Maynooth 17 miles. That suggests that, pro rata, Maynooth could be apportioned €60 million of that.

A Google for ‘travel time cost site:transport.ie’ yields the snappily entitled ‘Cost Benefit Parameters and Application Rules for Transport Project Appraisal’ here A quick browse suggests that €8 an hour is a reasonable costing for commuting time.

The Maynooth line serves about 10,000 per day I think? which I take it converts to about 2.5 million a year. From the example above, knocking 10 minutes off the Maynooth journey time would seem feasible. That’s about an estimated €3 million per year value on this social benefit. So if it cost, say, a ballpark €60 million to do it (which seems in line with the rough figures above), 20 years worth of shorter commuting time would justify it. Given the expected increasing in population along the line, the justification might come sooner.

Also, it is simply a fact that we have to reduce oil dependency in some way and hence generate electricity in some kind of sustainable manner. So on the face of it, while these back of envelope calculations are very crude, I can see how there very likely is a point in electrification of the Kildare/Maynooth/Drogheda lines.

dr zoidberg · 25-07-2006 11:32pm

It should also be noted that the catchment area around the Maynooth line is in fact greater than that of the southside DART line and is anticipated to grow significantly (although by 2016 the northern line will have a slightly greater catchment) - see here, page 6.

While the case for electric is quite borderline cost-wise Maynooth line electrification is surely one of the more feasibile proposals.

MarkoP11 · 26-07-2006 12:35pm

The tenders have already been issued for extra DART rolling stock up to 200 coaches, Maynooth line is the first to be electrified and a lot of the civil works have already been done, all the bridges as far as I know are sufficently high

Before everyone gets excited the extra stations on the Maynooth line, 2 possibly 3 will more or less equalise the journey time savings from going electric, at the moment journey times vary significantly depending on the time of day that should disappear

The Maynooth line already has the most powerfull diesel powered trains in the fleet so a seriously dramatic journey time reduction is not expected.

markpb · 26-07-2006 3:01pm

MarkoP11 wrote:

The tenders have already been issued for extra DART rolling stock up to 200 coaches, Maynooth line is the first to be electrified and a lot of the civil works have already been done, all the bridges as far as I know are sufficently high

Is there any indication of when this might start and how long it will take?

Red Alert · 26-07-2006 3:43pm

What are they using on Maynooth? Most powerful diesel trains per se are multiple-unit 201 locomotives.

Victor · 26-07-2006 9:26pm

Any suggestions of a schedule for the works?

MarkoP11 wrote:

The tenders have already been issued for extra DART rolling stock up to 200 coaches, Maynooth line is the first to be electrified and a lot of the civil works have already been done, all the bridges as far as I know are sufficently high

There is still the matter of the existing level crossings.

Before everyone gets excited the extra stations on the Maynooth line, 2 possibly 3 will more or less equalise the journey time savings from going electric, at the moment journey times vary significantly depending on the time of day that should disappear

I think the improvement in frequency will more than make up for the marginally longer travel time. Alternatively, some of the trains that start further out could operate semi-express on inner sections.

What's the deal with electric?

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