Great Western Coffee Shop

Sky news item on Thursday morning about the first 100mph bio trains.

But is it "bio"?  Is this the same story:

https://www.gloucestershirelive.co.uk/news/uk-world-news/uks-first-100mph-battery-diesel-6632329


It reads a bit woolly to me about how the batteries are charged - I suspect they're used to level out engine running speed to make it more efficient, charging the batteries at times of low load when energy would otherwise be wasted, and then used at times that full, inefficient diesel power would have been needed in the past.  In my reading, still a diesel train, though one with a far better fuel and environment profile.

Chiltern are stated as being a diesel only franchise.  Are there any other franchises which are still 100% diesel? Cross Country?  Transport for Wales?

I’m pretty sure XC are.

Chiltern’s train above is designed to use battery at & leaving stations such that there’s no exhaust fumes around them, particularly at terminus stations like Marylebone

For me, there are far too many confusing uses of similar names for railway power stuff nowadays.  AIUI this is a production scale development of a Hybrid power pack, as demonstrated in that Hitachi modified HST power car quite a few years ago.  So a battery fitted DMU.  This has noise and pollution reduction benefits that were possibly not emphasised so much with the Hitachi version, which IIRC was all about performance benefits and economy.

But what other uses of “hybrid” would I find if I looked? 
Firstly hybrid is fairly regularly used to describe bi-mode traction, powered by electricity OR diesel, such as in the IEPs.  Then there’s the “hybrid” DMU or EMU, used when a unit has been formed up out of individual carriages that weren’t originally delivered as one. 

Other “Hy” derivatives might be Hy-drive, Hydro-drive, (so is that hydraulic or hydrogen?), etc etc…

Paul  ???

This caught my... ear. Having been away from major stations for a bit, one of the standout features of changing trains at Bristol Temple Meads at the weekend was how incredibly noisy GWRs... are they 166s... are for passengers on a platform. Also particularly bad from the Hammersmith and City underground platforms at Paddington unless the pattern of use of the main line platform alongside has changed. Hopefully this is something that will catch on.

Hardly any trains on diesel use Paddington any more, so the H&C Line platforms are now so much better to wait on with Platform 14 usually occupied with an 8-car 387. 

The whole station is now a much quieter and pleasant place with screeching brakes and loud engines on 180s and smoky HST power cars a thing of the past.

Please don't shoot the messenger,I only posted the info as I saw it on Sky News,

If you don't agree with any posting,just e-mail the poster concerned.

This was announced by Porterbrook et al last July, and all the details are on this previous thread (http://www.firstgreatwestern.info/coffeeshop/index.php?topic=20412.msg247035#msg247035).

Ooh. Regenerative braking too.

Sorry - last July was the "launch", whatever that means. The original project announcement (at the start of that thread) was in 2018, which makes the timescale more plausible. So today is the first one - a prototype in some sense - going into passenger service.

Who thinks it will do better for reliability than Porterbrook's other re-engining project?

Sorry - no intent to shoot a messenger - rather intent to "shoot" Sky News who you were just reporting.  Yes, where a member makes a significant error of fact I would tend to send a personal message to let him/her know my concerns.

So far as I can tell, these trains are still 100% diesel powered. When in battery mode they use energy stored in the batteries. These batteries were charged from the diesel engines at times when full diesel power was not needed.

This makes better use of diesel fuel, but still 100% diesel powered. Smaller diesel engines may be used, or existing diesel engines may, in conjunction with battery storage, power a longer train.

A forward step, but a rather small forward step. Not comparable to an electric train powered from OHLE or from conductor rails, nor comparable to a battery train that is charged from a "shore" supply, or from electrification infrastructure.

Disagree (again)

Emission figures will be zero at the times that it's running on battery. It will not emit extra emissions when charging said battery, thus a net loss in emissions. Convert the fleet & that's a major saving

Figures reported earlier in this thread:
Fuel consumption - down by 25%
CO2 emissions - down by 25%
Noise - down by 75% (average or maximum noise?)
Nitrogen dioxide - down by 70%

I'll leave each member to come to their own decision as to whether that's "a rather small step forward", "a major saving", or indeed both (both a small step when so much more is possible, but a major saving because there's just so far to go)

There will indeed be no emissions in battery mode, but in diesel mode there will be EXTRA emissions in order to produce the energy used to charge the battery.

A reduction of 25% in fuel consumption and therefore also a reduction of 25% in carbon dioxide emissions is a relatively small reduction if compared to the use of an electric train. (battery powered or OHLE powered)

Again, disagree - charging only while not using all the power generated, so no increase while diesel running/burning.

And 25% is 25% (a quarter reduction) is a large amount, sorry. Yes, 100% saving (less whatever it takes to generate that leccy) is huge - but you can't seriously deny 25% is still a large reduction (unless the 100% is considered negligible, in which case why are we bothering?)

I can not agree.

How is a diesel engine to produce extra power (whether to charge a battery or for any other purpose) without also burning more fuel and producing greater emissions of carbon dioxide ?

It is basic physics, that to produce more output power will require more fuel.

I wonder what percentage of the battery charging comes from the diesel engine and what percentage comes from regenerative braking?

The reference to Aylesbury is a bit misleading as I'm pretty sure no stretch of the Aylesbury-Marylebone direct line allows 100mph running. The train will presumably be based at Chiltern's Aylesbury depot but as the article says, it is also going to be used on the Marylebone-High Wycombe-Oxford line where it will indeed be able to reach 100 mph.  I'm staying out of the hybrid good/bad discussion; it's far from clearcut, although at the very least I suppose it does allow aspects of battery technology to be explored which might be of clear benefit in future.

Surely it depends on how much of the battery charging is from regeneration on braking - likely to be a greater proportion on suburban services with many stops? So not all of that battery power has resulted in extra emissions.

And the comparison with electric needs to recognise that there is still a carbon footprint with electric, so a 25% saving is a greater proportion of potential saving you would get if the service was electrified. (eg, if a fully electric service resulted in a reduction in carbon emissions of 80%, then the proportionate saving of the hybrid approach is 25/80 =31%).

If you can get that sort of saving in a couple of years from modifying existing rolling stock that sounds like a no-brainer given the costs and timescales involved in a large scale electrification programme (assuming the trains have a long enough expected life to make it financially viable).

There's also the improvement in local air quality and noise to consider too, apparently a big issue at Marylebone. At the places where it is likely to be an issue, you get more or less the full benefit of electrification with this solution. 

A GWR insider posting in the WNXX forum reckons it’s almost certainly not happening to any of the GWR fleet.  Every year the DfT and treasury delay it just reduces the BCR further.

I don’t think many people are expecting Chiltern to go for more conversions, their current “national rail contract” with DfT apparently only allows for two demonstrators.

Paul

There is however a reasonable amount of more modern dmu stock where the BCR is likely to be more attractive. Though given I gather operating companies need treasury approval for every paper clip ordered these days, I suspect the environmental benefit will be given minimal weighting in any assessment unfortunately, despite all the claims to the contrary about trying to promote a green railway.

Not quite. I believe that there's a cap of £1,000 [on train repairs] without sign-off from the DfT, and that could include quite a few paper clips if it's to pin together the paperwork thus generated  ;D ;D ... confirmation of that, or "just a rumour without substance" would be interesting!

It’s now being suggested in Rail UK forums that the second demonstrator has been cancelled, (although no official quote).  For me that lengthens the odds we won’t be see it in any GWR trains.