[steveintoronto]

Electrolysis does require quite a bit of electricity (I'm not sure how it compares to catenary)

A lot has to do with the voltage and current used for catenary as to resultant efficiency of conversion (Power in, power out, source to use).

Older low voltage DC systems were and still are quite inefficient, line loss being one aspect, rectification if needed being another (efficiency of AC in, DC out rotary converters also low) and of course, and other factors, not least due to conversion of AC generation grids to a DC system.

Conversion transformers in HV AC systems are now very efficient, "insertion loss" is very low, perhaps a few % or lower, plus autotransformers halve even that loss, and decrease the 'source impedance' (the degree of 'stiffness' under duress of load, so they don't 'sag' under load). Modern HV AC (25kV or higher)(50kV is used in a split winding arrangement too technical to go into here, but all long distance systems use a form of this) is very to highly efficient. To put that in perspective *multiples times more efficient* than generating Hydrogen and delivering it to point of use.

Best I leave this discussion at this point, save for being open to specific technical questions from readers. When I hear "Hydrail" being used in the context Ontario is now using, I think of Snake Oil. Snake Oil is great stuff, lube your skateboard with it....wheeee! Excellent in political whistles too...But it doesn't cure any ills. In fact, it makes them worse.

Addendum: Excellent non-technical discussion on HV AC here:

Power supply efficiency on a line equipped with 25kV ac overhead contact wire is also 98% although this may vary depending on rolling stock.

http://www.railjournal.com/index.ph...ion-choices-overhead-ac-vs-third-rail-dc.html

That's the takeaway for this forum string re Hydrogen overall conversion efficiency (which comes nowhere close, even in nations like Germany with a *probationary* national program to generate it).

Link provided also an excellent description, indirectly, of metros (with overhead 25kV AC catenary) v subways. If someone asks a technical question, I'll link to some engineering references.

Here's another excellent non-technically written piece, re MTA (New York) Metro-North electrification. Due to similar climate and running conditions, this pertains more accurately to Ontario's needs:

[...]
ØDC driven third-rail is less efficient. Trains accelerate much faster using overhead AC voltage, the power source used by the fastest trains in the world… the TGV, Shinkansen, etc. On third-rail speeds, are limited to 75 miles an hour vs. 90 mph under the wire. That means, mile for mile, commute time is longer using third rail. [...]

http://talkingtransportation.blogspot.ca/2008/01/catenary-vs-third-rail.html

In effect, *at best* Hydrail is the equivalent of a third rail DC system. Any advantage it will have is due to the 'source impedance' of the batteries that H conversion charges, but just like a starting motor in a car, that 'crank time' is very limited, and especially in colder weather. Once that battery is flat, you're running on the rough equivalent of a lawn mower engine.

Think about it. And think how the public is being taken to the cleaners on this, preying on the public's widespread ignorance of simple technical issues.

Some prototypes run great! Under controlled conditions bereft of real world occurrences.

And of course, Hydrail is about to be replaced by rocket ships, which run on corn mash, and will get you from London, Ont to Toronto in a spif. Details to follow...

 

[lenaitch]

Actually the Ring of Fire has huge potential for hydroelectric power generation. I am hoping a similar agreement with locals similar to Quebec where the economic growth has really helped the education and social aspects of all communities nearby (both native and non-native)

I disagree. The RoF is in the Hudson/James Bay Lowland which is essentially a large peat bog cut by slow moving rivers. Even inland - west towards the Manitoba border - it is relatively flat. Pickle Lake, about 550km from the coast, is less than 400m ASL. Moving west from that and you get into the Lake Winnipeg/Nelson River drainage basin. The only way to create either flow or head is through massive diversions and civil works. The embayed water would have to be prevented from flowing west into Manitoba which is part of the same watershed. If you fly over the area or even look at it in Google Earth, it is a mass of small featureless lakes, rivers and bogs. Northern Quebec is much more 'mountainous' with fewer but larger rivers, which allowed for fewer diversions and large embayments because of the valleys.

Assuming it would be financially feasible, which I argue it is not, environmentally disruptive civil works like the Hydro Quebec James Bay Project are no longer on the table. While there have been some economic spin-offs for area communities in terms of jobs, the largest financial impact has been from the $Millions paid by the province.

The RoF doesn't really need massive power anyway since they are planning to locate the smelters elsewhere.

 

[KevinT]

Older low voltage DC systems were and still are quite inefficient, line loss being one aspect, rectification if needed being another (efficiency of AC in, DC out rotary converters also low) and of course, and other factors, not least due to conversion of AC generation grids to a DC system.

DC conversion has gotten quite a bit more efficient as well thanks to solid state electronics (i.e. big diodes), with rotary converters and ignitrons gone the way of the dinosaur. 3 phase AC gives you 6-pulse rectification, but using two step down transformers with one wired as delta-delta and the other as delta-wye gives you 6 phases for 12-pulse rectification, with a very smooth DC output. It's what all the cool LRT systems are doing these days.

 

[steveintoronto]

DC conversion has gotten quite a bit more efficient as well thanks to solid state electronics (i.e. big diodes), with rotary converters and ignitrons gone the way of the dinosaur. 3 phase AC gives you 6-pulse rectification, but using two step down transformers with one wired as delta-delta and the other as delta-wye gives you 6 phases for 12-pulse rectification, with a very smooth DC output. It's what all the cool LRT systems are doing these days.

But don't forget you're reconstituting DC to AC to DC to do that, with insertion loss at each conversion. Some of that loss can be tolerated in the chopping stage of gate control, but no matter how you cut it, (pun fully intended), for larger heavy rail vehicles, HV AC catenary is better in many respects.

But getting back to the Hydrail simile, no matter how you process the current out of the battery, the torque curve being sustained is only as good as the source impedance of the battery, whether you constitute it into triple phase or any other form. Once that battery capacity starts waning, all that's left is what the fuel cell can produce, and that's somewhat analogous to running your car on the starting motor. That can work in an emergency, but it's no way to power a train unless the battery can be recharged at points along the line.

There's a serious limitation with H fuel cells right now. That cannot produce enough output for full sized trains. Could that happen some time in the future? Perhaps...solar cells have multiplied in yield in a little over a decade.

Fuel cells (at least the osmotic configuration) are up against a theoretical limit.

Here's the claims from the US DOE
https://www.energy.gov/sites/prod/files/2017/10/f37/fcto-progress-fact-sheet-august-2017.pdf

Lots of hope, very little tangible. All sorts of "breakthroughs" over the last decade...with little to show for it.

Meantime, indications are that fuel cells using other feed-stocks than H are looking more promising: (It has to be remembered that Hydrogen is one of the weaker Hydro-Carbon gases, Methane and Propane both vastly more energy dense per weight/volume. That Carbon counts for a lot, depending on the chemistry)

Exxon Quietly Researching Hundreds of Green Projects
By
Anna Hirtenstein
3 November 2017, 01:00 GMT-4 Corrected 3 November 2017, 13:04 GMT-4
[...]
Projects it’s working on include:

• Algae biofuels: Exxon is planning to harvest algae in ponds or oceans around the world and process it into a biofuel for regional distribution. Swarup expects that it will first be blended with diesel and jet fuel, but the goal is to eventually sell a 100 percent algae-derived fuel.
• Biodiesel made from agricultural waste. The company is working with Renewable Energy Group Inc. to use microbes to convert inedible crop residue like corn husks into biofuels. The two companies began their collaboration in 2016 and recently extended their joint research program.
• Carbonate fuel cells: Most fuel cells generate electricity by reacting chemically with natural gas or hydrogen. These ones use carbon dioxide. Exxon and FuelCell Energy Inc. are researching how the devices can be used in carbon capture and storage and to generate electricity at the same time. It’s building a pilot plant within a few months and is working on the engineering of the facility now.
• Process intensification: Exxon is working with Georgia Institute of Technology to develop a more efficient way of refining crude oil into plastic. It involves using a membrane and osmosis rather than heat. Exxon is targeting carbon dioxide emission reductions by as much as half with the process.

“We are still 10 plus years away” for both the algae biofuels and carbonate fuel cells to be deployed at scale, according to Swarup, who said the company’s been focusing research on algae for eight years.

[...]

https://www.bloomberg.com/news/arti...ing-1-billion-a-year-to-research-green-energy

Hydrogen just happened to float into view as a convenient excuse to obfuscate the promise of "Electrification for Ontarians".

The way to move forward is clear: Start erecting the catenary. And start yesterday.

 

[jamincan]

Bear with me, I'm trying to make sense of what a bunch of posters were talking about above. In comparing loss due to AC-DC conversion and vice versa, I'm assuming both a hypothetical hydrogen plant and the LRT are receiving AC power from the grid.

Hydrail would require AC->DC conversion from the grid to produce hydrogen via electrolysis. The fuel cell would likely produce DC which could supply the drive directly, which would then produce AC for the motors. So it's converting AC->DC->AC

750VDC overhead lines would require AC->DC conversion to supply the lines, and then DC->AC in the drive to supply the motor, so once again AC->DC->AC.

25kVAC overhead lines would require AC->DC to supply the drive on the vehicle, and then DC->AC in the drive to supply the motor, so once again AC->DC->AC.

It seems to me, then, that there's not really any difference for all of them with regard to the loss due to conversion and that can be disregarded. Am I misunderstanding something here?

 

[dowlingm]

@jamincan 1500V more likely for DC overhead (e.g. Dublin, Chicago, Montreal REM)

 

[steveintoronto]

Hydrail would require AC->DC conversion from the grid to produce hydrogen via electrolysis. The fuel cell would likely produce DC which could supply the drive directly, which would then produce AC for the motors. So it's converting AC->DC->AC

You're actually doing well in understanding current reformation stages, and AC->DC can be very efficient with just the forward bias loss of the solid state diodes being the insertion loss, presuming it's full wave rectification which is almost always a given. (In the past, before solid state diodes, mercury vapour rectifiers displayed a massive loss, somewhere in the region of 30% and loss of low source impedance too)(loss of regulation)
Where losses become more significant is in reforming *smoothed* (filtered) DC back to AC, usually at a higher line frequency than the source to reduce core losses in transformers and/or other inductive devices like motors.

Of course, the advantage of a low voltage tram/third rail subway type supply is the ability to run the motors at local line voltage as the rectification and step-down transformer isn't carried on-board, but is stationary at the power houses along the line (needed far more often as local supply voltage decreases). There-in alone is a huge loss of efficiency in numbers of powersheds needed.

I'm not explaining this the best, so I'll find a more technical link to quote. Main supply is not my forte, I'm more in the electronic end of things and devices. I have been involved in toroidal transformer development, albeit for audio, all single phase.

3 phase AC gives you 6-pulse rectification, but using two step down transformers with one wired as delta-delta and the other as delta-wye gives you 6 phases for 12-pulse rectification, with a very smooth DC output.

Wow, I was unaware of this. This is the work of Satan! lol...Multiphase is a whole area of power supply not usually needing awareness at the device end, as bar a few examples in the past, maybe one or two oddities now, all supply at the device end is two pole single phase, considered so even if unfiltered pulsed DC.
https://en.wikipedia.org/wiki/Three-phase_AC_railway_electrification

A technical discussion for what you describe is here: http://www.origocorp.com/WhitePaper/PhaseAttributes.pdf

What I can add to that is that with more 'smoothing' comes less *peak* torque in an electric motor. Power may stay the same, but the 'torque peaks' are less. For readers to understand how this can be, think torque wrenches with their 'hammer' pulses. Or internal combustion engines with just one cylinder, the latter still the choice for dirt bikes, as they can 'hammer' their way out of the mud.
motorcycle - Why (almost) all dirt bikes have single cylinder ...
(caveat to this link: First two answers completely miss the torque aspect, they're thinking power. Third answer has it right)

This has more significance for starting a train from a standstill, (or even starting motors on highly accurate synchronous devices like audio turntables that 'lock-in' to the line frequency, but again, best I find a link that explains this all for electromotive traction and fuel cell derivation of DC and the needed reformation and losses involved in doing it this way).

Footnote to Kevin: Back in the days of my youth, in the 1800s, when cars had only AM receivers, I often wondered why the induced buzz under streetcar lines was higher than what I would have understood to be 120 cycle hum. I thought it was just 'hash' from dirty rectification. It must have been 240 cy and dirty. It used to drive people crazy back in those days...lol...and thus why most of your folks haven't fully recovered to this day....Chuck Berry chopped...

 

[KevinT]

Equating AC to DC conversion to the cylinders of an engine is a good analogy @steveintoronto, rectifying single phase AC is like having a V-twin, 3 phase like a V6, and 12-pulse like a V12: Way smoother power delivery.

For mainline electrified rail with 25 kV AC overhead it's the V-twin scenario if regulated with a full wave diode bridge. I assume modern trains do something more akin to a switch mode power supply to create onboard DC, but haven't looked into it. If they did it could greatly reduce the transformer size/weight, but at the cost of a good deal more complexity.

We've gotten way off on a tangent here but hopefully it's a useful conversation for some of you. If not, sorry all!

 

[steveintoronto]

We've gotten way off on a tangent here but hopefully it's a useful conversation for some of you. If not, sorry all!

I don't think we have, albeit this is testing the perimeter, as @jamincan 's post shows at least some readers are able to get a context of what's involved. We do have to tie it back to fuel cells though, but without getting so watered down as to allow Queen's Park and the UK's Transport Minister to pull the technical wool over peoples eyes.

For the record, I and a number of other posters do see value in the Hydrail approach. It fills a certain niche very nicely. But *politically* it's being used as an excuse to not do what has to be done, and that's the present state of the art electrification of the backbone of GO's rail system, and not dally about 'the future state of the art'.

You could spend a long time not buying a car waiting for the promised Popular Mechanics 'nuclear powered flying car' to arrive to get you to work.

Addendum: Here's from Rail Engineer, who claim to be pro Hydrail....*with caveats!*. They've run specials on the topic, but here's one of the provisos: ("Johnson" is Boris Johnson)

[...]
Hydrogen and battery technologies offer significant benefits, which will no doubt be developed further. However, their low energy densities will always be a significant constraint. For this reason, there is no prospect of self-powered rail traction using alternative fuels for high-power rail traction. Rail Freight Group executive director Maggie Simpson made this point in her response to Johnson’s statement. She noted that, whilst battery and hydrogen ‘may show promise for lightweight passenger trains, their application for heavy duty freight is at best unproven and setting an arbitrary deadline of 2040 could well therefore be counterproductive, damaging the case for investment’. She advised that RFG would like to see the “continued affordable electrification of the strategic freight network”.

Yet, in his call for the railway to decarbonise, Johnson expects that batteries and hydrogen will replace the diesel engines on bi-mode trains. His advisers would seem to be unaware of the fundamental constraints of these technologies. In his speech, Johnson also seemed to dismiss electrification by stating that it was “unlikely to be the most cost-effective way to secure these vital environmental benefits”.

Zero-carbon electrification

Although Johnson’s expectation that greener alternatives will replace diesel is not unreasonable for lightly used lines, this aspiration is unrealistic for busy core routes that require high-powered traction. For these, electrification is the only option that offers the prospective of zero-carbon rail traction as an increasing proportion of Britain’s electricity becomes generated by renewals. The use of wind turbines to provide all the power for electrified railways in the Netherlands shows what can be done.

Furthermore, busy electrified routes carry far more traffic than rural lines, and so offer far greater environmental benefits than alternative-fuelled self-powered vehicles.

Whilst electrification’s high initial capital cost gives it a poor business case for rural routes, this is not the case for busy main lines. The economic case for electrification is recognised by many countries that have a high percentage of their rail network electrified. These include Netherlands (76 per cent), Italy (71 per cent) and Spain (61 per cent). In the UK, just 42 per cent of the network is electrified.

Electrification offers improved passenger benefits with its greater acceleration and speed. For example, a bi-mode class 800/2 has a power to weight ratio of 11.2kW/tonne in electric mode and 6.9kW/tonne in diesel mode.

Electrification also offers enormous operational cost savings. A recent report by the Office of Rail and Road (ORR) on rolling stock costs showed that, whilst the Virgin Trains fleet portfolio includes only 15 per cent diesel rolling stock, diesel accounts for 40 per cent of its total energy costs, making it around four times the cost of electric traction. One reason for this is that, unlike diesels, electric trains can absorb the huge amount of energy required to brake a train and regenerate it back into the grid.

The high maintenance and capital cost of diesel trains is illustrated in a National Audit Office report that considered the procurement of Hitachi IEP bi-mode trains, which includes a 28-year maintenance contract. This showed that the Great Western IEPs, which frequently operate under diesel power, cost £4 million more per vehicle than the mostly all-electric East Coast IEPs.

That's the technical argument above. Here's the *political* one, this is almost an exact mirror image of the Ontario obfuscation:
(Article continues)

Unnecessarily high electrification costs

The Government, not unreasonably, considers the current high cost of electrification to be unacceptable and has cut back electrification schemes as a result. The recent feature “Electrification as it used to be” (issue 158, December 2017) showed that, at today’s prices, the cost of electrifying the Great Western main line is seven times the track-mile-cost of British Rail’s East coast electrification. Whilst this is not a totally fair comparison, given changes to standards and the increase in traffic since the days of BR, it does show the need to understand why Great Western electrification cost so much.

In its report ‘A breath of fresh air: new solutions to reduce transport emissions’, the Institution of Mechanical Engineers recommended that the “DfT instructs Network Rail to develop an appropriate specification for railway electrification, which will achieve an affordable business case for a rolling programme to complete the electrification of main lines between Britain’s principal cities and ports, and of urban rail networks through our major city centres.” In making this recommendation, the Institution believes it should be possible to drive down electrification costs and is also suggesting that having a rolling programme, as is the case in Scotland, is one way of doing this.

Jo Johnson is right to suggest that hydrogen and batteries can decarbonise rail traction. However, for very real engineering reasons, they can only be part of the solution.

The politics of electrification are such that the Government is forced to make misleading statements to justify its cutbacks. For example, Chris Grayling’s recent statement that, with bi-mode trains, “we no longer need to electrify every line to achieve the same significant improvements to journeys”, ignores the laws of physics – improved journey times requires more powerful trains. An electrically powered bi-mode is almost fifty percent more powerful than a diesel bi-mode.

The industry’s response to Johnson’s call for decarbonisation solutions must focus on engineering issues. If so, it can only reach the same conclusion that the Institution of Mechanical Engineers has, which is that cost-effective electrification is the only way to deliver significant carbon and emission reductions.

This article was written by David Shirres.

Read more: Hydrail comes of age

https://www.railengineer.uk/2018/03/05/is-hydrogen-the-answer/

TVO has run a number of stories on this, here's two:

The Liberals think hydrogen trains are the future — but what if they're wrong?
ANALYSIS: Metrolinx has ordered hydrogen-powered trains for GO Transit. But even the companies eager to sell them can’t promise they’ll actually work, writes John Michael McGrath
https://tvo.org/article/current-aff...ains-are-the-future--but-what-if-theyre-wrong

Ontario is thinking about hydrogen-powered trains. Why?
OPINION: The province has a long history of considering electrified commuter trains, and then choosing something else instead. Here’s hoping history doesn’t repeat itself
https://tvo.org/article/current-aff...is-thinking-about-hydrogen-powered-trains-why

 

[mdrejhon]

Relevant to this thread is a tweet that I saw today about Monday's "Ask Metrolinx" open house town hall event. (You can attend in person after work tomorrow. See www.metrolinxengage.com ...)

 

[steveintoronto]

Then Phil should make clear: What is?

 

[Streety McCarface]

Then Phil should make clear: What is?

CN

 

[steveintoronto]

CN

CN have nothing to do with the tracks on the UP and the many other kilometers of GO owned trackage. Is RER going to be diesel? Maybe it should be steam or horse-drawn at this rate?

Addendum: On reconsideration, clockwork trains might be the best solution. Politicians are very adept at winding people up, so they could be positioned at each end of the line, with a clockwork key, and wind up the train so it could crawl to the other end of the line.

And then blame it on CN...

 

[steveintoronto]

Relevant to this thread is a tweet that I saw today about Monday's "Ask Metrolinx" open house town hall event. (You can attend in person after work tomorrow. See www.metrolinxengage.com ...)

I can't think of a better example of the need to re-introduce the hyphen into English language common-use than from your link:
Stop Naming Hurontario LRT

lol...it reads the exact opposite of what they intend to state:
"Help Metrolinx determine eight new station stop names for the Hurontario LRT". Is it any wonder the iGeneration are so easily misled?

 

[Streety McCarface]

CN have nothing to do with the tracks on the UP and the many other kilometers of GO owned trackage. Is RER going to be diesel? Maybe it should be steam or horse-drawn at this rate?

Addendum: On reconsideration, clockwork trains might be the best solution. Politicians are very adept at winding people up, so they could be positioned at each end of the line, with a clockwork key, and wind up the train so it could crawl to the other end of the line.

And then blame it on CN...

Was cynically referring to the Kitchener line between Bramalea and Kitchener.

Side note: operational issues on the Barrie line among other things come to mind.