Battery powered Electrostar

[brianthegiant]

I'm not at all convinced about solar panels on train roofs, at any one time at least half the roof wouldn't be facing south. Not to mention shading from tunnels, & other structures. As a rule of thumb you get about 100W max per square metre of panels. So you need a significant area to get a significant amount of power. Much more sensible to put solar panels on all the Station roofs which are south facing +/- 90deg, providing they're not significantly shaded by trees/buildings. Blackfriars would be a good case study.

On the battery front, my experience is that batteries are expensive to operate, given the limited cycle life. This project will be useful to get some robust costings. A key question is whether you have enough dwell time at stations to keep the batteries topped up. Furthermore, what would be the cost of installing a network connection and 11kV:25kV transformer for a short section of OHL & whether the local 11kV network would have enough capacity. If you end up needing significant lengths of new HV underground/overhead cables for supply, then combined with the cost of batteries & inverter/chargers the cost saving against electrification start to become marginalised.

Furthermore, even if the battery system is designed with a significant energy storage contingency to allow for delays, battery ageing, etc, nonetheless you are adding complexity to a critical system, so there are more failure modes and lower reliability.

 

[Mikey C]

An interesting idea, though batteries are VERY heavy, so there would be a loss of efficiency in normal operation. It would take a lot of battery power to power a modern air conditioned coach as well.

 

[jon0844]

Just as I read about advances in solar energy (and more efficient, multiple layered panels), I guess we are about due for some major advance in battery technology too.

This has been talked about for years, and obviously is a high priority for the consumer electronics and computing industries. Sadly, little seems to have happened and the only real improvements in battery life has been down to reducing power consumption.

Fine for a train that will have low powered electronics, lighting - but probably no good for the motors and air conditioning systems, and let's not forget the heating.

Batteries also perform differently at different temperatures, so on a very hot day you might have further problems. Of course, that's the point of doing trials.

 

[jopsuk]

Batteries generally deliver more power when warmer, though they also obviously have a higher risk of bursting into flames when warm.

 

[JamesRowden]

Batteries generally deliver more power when warmer, though they also obviously have a higher risk of bursting into flames when warm.

Batteries work most efficiently at different temperatures.

 

[jon0844]

Batteries generally deliver more power when warmer, though they also obviously have a higher risk of bursting into flames when warm.

Not on my phone. On a very hot day, the battery gets warm and runs down quicker. Or perhaps I should say, appears to.. same result.

Perhaps when it cools down, it regains some of that lost power, but that's not going to be a lot of use.

 

[broadgage]

This sounds an excellent idea, and somwhat overdue IMHO.
There are many routes that should be electrified, but that have short problematic sections due to limited clearences or sea water spray.

Battery power would be ideal for limited use in such circumstances, provided that MOST of the route is electrified then charging should be no problem.

If only short distances are to be covered on battery power, then it would be reasonable to turn the heating or air conditioning off whilst on battery.

If more than say 20 miles needs to be covered on battery power, then to me that suggests that either diesel power or more electrification is called for.

A 4 car electric train might reasonably have an average power consumption of 300KW. If it runs for half an hour in battery mode, then allowing for battery losses, about 180 KWH would be needed for charging.

If charging in 30 minutes is required, then that is an input of 360 KW needed at the charging point, plus heating/air conditioning and lighting. Say 400KW in total needed.
That should be readily available in most urban areas, but not in rural places without costly grid upgrades.

(400KW is about the average demand of 400 homes)

 

[Aictos]

The report clearly states (my bold) The modified train will then undergo a variety of tests ‘off network’. If these tests prove successful, the train will then run on an electrified branch line on the Anglia route, yet to be chosen, with its pantograph down. This is so that if there is a problem, it can raise its pantograph, and collect power again.
So I would suggest Walton - on the- Naze, Braintree, Chingford, or if they are really unsure Romford to Upminster

I was going to say Hertford East to Broxbourne, are 379s cleared on that branch?

 

[jopsuk]

I'd have thought they'd want a self-contained branch- is it possible to reverse on the Hertford branch without going to Broxbourne?

 

[59CosG95]

IMHO, I think electrify the MAIN lines, and convert branches to battery operation. This would be ideal for all the little Cornish branch lines!

 

[mr_jrt]

Supercapacitors are more applicable than batteries here. Quick to charge and efficient when discharging. Having inductive charging installed at stations should help keep them topped up. Batteries would take far too long to charge.

http://www.extremetech.com/computin...ing-process-rivals-lead-acid-battery-capacity
http://www.geek.com/science/student...at-enables-30-second-battery-charges-1555756/

 

[JamesRowden]

IMHO, I think electrify the MAIN lines, and convert branches to battery operation. This would be ideal for all the little Cornish branch lines!

Would you have robots changing the train's batteries at the termini and along any long routes?

Supercapacitors are more applicable than batteries here. Quick to charge and efficient when discharging. Having inductive charging installed at stations should help keep them topped up. Batteries would take far too long to charge.

Supercapacitors have far lower energy density (about a tenth) and so presently would only be applicable to short sections of non-electrification (up to ~2 miles).

 

[HSTEd]

This is just thorwing money away on something that will almost certainly never be practical.
The mass of batteries would be prohibitively heavy and expensive for actual operational use.


This is just a typical British attempt to escape the capital spend required for electrification by hamstringing the railway operationally.

 

[joeykins82]

If the sections around stations were electrified presumably the pantograph could be raised to charge the batteries whilst dwelling and the OHLE feed used for pulling away from stationary

 

[LexyBoy]

Supercapacitors are more applicable than batteries here. Quick to charge and efficient when discharging. Having inductive charging installed at stations should help keep them topped up. Batteries would take far too long to charge.

Not yet; supercapacitors have nowhere like the energy density of the batteries being discussed. The high capacity SCs in the links are a long way from real-world applications.

Sodium-NiCl2 and lithium-iron phosphate batteries hold around 100 Wh/kg, whilst supercapacitors hold around 20 Wh/kg. These types of batteries can be recharged in around an hour - still quite a while, but improving and not unreasonable especially if part of the route is under the wires.

This is just thorwing money away on something that will almost certainly never be practical.
The mass of batteries would be prohibitively heavy and expensive for actual operational use.

I disagree. ATOC data (p6 here) indicate that passenger train electricity consumption is around 2 KWh per vehicle km. Thus for a 4-car train to have a 100 km range (say 2 round trips of a ~20 km branch), we would need 800 KWh capacity, i.e. 8000 kg of batteries. That sounds entirely reasonable to place under one or two coaches in such a train - in reality less may be needed as the 2 KWh/km figure will include intercity services, and includes distributive losses.

It's nice to see NR looking for innovative solutions anyway - we'll have to wait for the outcome of the trial to see about viability.

This is just a typical British attempt to escape the capital spend required for electrification by hamstringing the railway operationally.

The same argument is used against IEP bi-mode - just as in that case battery-electric may allow economies of scale and render later electrification viable. If this had been successfully tested ten years ago we may have ended up with an IEP using batteries rather than diesels off the wires.

 

[JamesRowden]

If the sections around stations were electrified presumably the pantograph could be raised to charge the batteries whilst dwelling and the OHLE feed used for pulling away from stationary

Batteries can be discharged without damaging them far faster than they can be charged (~4 times). This may limit much of the route would not be electrified.

 

[jopsuk]

I know intercity trains have big current draw when starting, but overall, does a train that mainly cruises at 160km/h+ use more or less power per km than one accelerating a full load every three or four km? Obviously with regen brakes the balance shifts.

 

[jon0844]

What about OHLE at stations (to charge the batteries when stopped, even if for just 1 or 2 minutes) and also for a set distance beyond the station to assist a train in its initial acceleration and conserve power. In terms of electrification, you now only need to put up wires for a very small percentage of the line (and perhaps other places where trains are likely to stop, such as ahead of certain signals or passing loops).

As for replacing batteries, I'd hope they'd be easily slotted in and out when the train goes in for routine maintenance (likely with a machine to do it, as is being tested on cars).

The thing is, in 5, 10, 20 or 50 years from now, I am sure we'll have seriously advanced battery technology while also reducing energy consumption even on electric motors, possibly found more efficient ways to cool and heat air, built new composit materials to reduce the weight of the trains and so on.

To me, this is an idea that will ultimately make a big difference to the future of rail (indeed ALL) travel - even air travel perhaps.

And if a train should run low on power on the move, simply ask every passenger to connect his/her mobile, smartphone, laptop, digital camera in and suck the power from there.

 

[HSTEd]

Overhead wiring is not the expensive part of electrification, it is primarily the grid taps and the like which would be require anyway for discontinuous electrification, remember that you would put peak loads through the roof which would make it more expensive to connect it to the grid, not less. (same total energy transfer but in less time).

NSodium-NiCl2 and lithium-iron phosphate batteries hold around 100 Wh/kg, whilst supercapacitors hold around 20 Wh/kg. These types of batteries can be recharged in around an hour - still quite a while, but improving and not unreasonable especially if part of the route is under the wires.

Rapid deep cycling like that will kill the packs rather quickly.

I disagree. ATOC data (p6 here) indicate that passenger train electricity consumption is around 2 KWh per vehicle km.

T618 'Traction Energy Metrics' puts the figure at 2.3kWh/vehicle.km for the Class 357 fleet.
So 2kWh is probably a reasonable figure although I would hazard that the figure will likely increase with the increasing mass of electronics in trains.

Thus for a 4-car train to have a 100 km range (say 2 round trips of a ~20 km branch), we would need 800 KWh capacity, i.e. 8000 kg of batteries.

Now you have to account for the batteries operating in suboptimal conditions (-10C and 5 years old) which could easily cut effective capacity in half.

That sounds entirely reasonable to place under one or two coaches in such a train - in reality less may be needed as the 2 KWh/km figure will include intercity services, and includes distributive losses.

Distributive losses which you will incur anyway since they will be higher for the lower than 25kV tap that you will use to charge the batteries on the branch?
And then you have to account for the fact that batteries don't have 100% round-trip efficiency.

The same argument is used against IEP bi-mode - just as in that case battery-electric may allow economies of scale and render later electrification viable. If this had been successfully tested ten years ago we may have ended up with an IEP using batteries rather than diesels off the wires.

You will end up deep cycling the battery every day, perhaps twice a day with that undersized battery pack.
Lithium Iron Phosphate batteries tend to have ~2000 cycles of life before reaching the EoL condition, which means it will probably last ~6 years at one cycle a day.
And if its a quite intensive hourly service you could cycle battery packs (mainly different ones) eight times a day, meaning that you replace battery packs on average every 9 months.

Even at the low end of Lithium Phosphate battery cost you are looking at ~£200,000 per pack.

Which means that over the ~40 year average life of electrification (weighted average based on prices of different life components) - that is 53 packs expended which is ~£10.5m at the least.
With the lithium supply squeeze and adding in more reasonable safety factors to avoid absurdly rapid cycling and you could be looking at double that in the future.

Now consider that a 20km branch would cost only ~£30m at most to electrify if single track, and the operational cost benefits that are lost by not electrifying it.
(You will never be able to run another kind of electric stock down that route and will have to maintain a microfleet).

EDIT:

And I am against IEP bi-mode as well, since the money could have brought in every electrification team in western europe.
I am not entirely sure how removing the need to do electrification of any branch lines at all will bring about economies of scale.
IEP bi-mode has essentially killed any possibility that the CrossCountry route will actually be electrified any time in the next 30 years.

 

[Prairie_5542]

I do wonder if a 4-car unit might be too much weight for the motors on battery power, though besides the reasons for this being mentioned, perhaps they need that much underfloor space to avoid all the gubbins eating into the passenger saloon. I assume that once they've ironed out any problems on the tests under the wires they'll switch to a trial on a non-electrified line. The Marks Tey-Sudbury branch would be an obvious candidate for this kind of operation in that part of the country, though would the platforms on there have space for a 379?

The 379s would be too big for this line.

 

[61653 HTAFC]

I have to say I think this is a good idea to at least try out- We won't know if it works unless we give it a go...

However, I do wonder if the trial might be hamstrung by taking place using a 4-car EMU with air-con and all that stuff that will put more strain on the batteries. Ideally, as the solution is most likely to be viable on lines such as (as I mentioned before) The Sudbury branch, and would be more efficient with a 'no-frills' type unit of 2/3 cars. Of course such a unit does not exist, so it would be more expensive to buld an entirely new train than to use a 379. In any case, if the trial is successful we might see the DfT deciding not to bother with wires to Windermere after all!

 

[broadgage]

I cant see the point in electrifying only at stations, or for a short stretch each side of the stations.
As others post this would probably cost almost as much as proper electrification.

The merit of battery power is for relatively short stretches that cant be economicly electrfied.
In tunnels with insufficient cleaances
In especialy scenic locations
Where subject to severe seawater spray
On heritage lines where it is desired to run the odd through train from the national network onto a route mainly worked by steam.
On relatively lightly used branches of an electrified mainline
And to permit of diverting trains via non electrified routes for engineering works

One day the route from Taunton to London will be electrified, battery power would be ideal for through running to the West Somerset Railway.
Only moderate battery capacity would be needed for the realtively short, relatively slow speed bit at the Minehead end. The great majority of the energy would be used on the much faster electrified main line.

Fast charging at Minehead would not be viable due to the capital costs of providing enough power.
Slow charging would help for any unit berthed overnight or for prolonged periods, and would allow cleaning, servicing, and preheating/cooling without any battery discharge.
A 3 phase 230/400 volt supply is available almost everywhere and would probably fully charge overnight, and help a bit even for short layovers.

I mention the WSR simply as an example, broadly similar circumstances apply at other places.

 

[Yew]

Flywheels. In a vacuum on good bearings. Spin them waaay fast, and have motors at every station to rev them up during standing times

 

[asylumxl]

Flywheels. In a vacuum on good bearings. Spin them waaay fast, and have motors at every station to rev them up during standing times

You mean like the larger Parry People Mover designs?

Didn't catch on unfortunately.

Super-capacitors are the way forward, particularly if new materials are developed to improve their performance in the near future.

 

[brianthegiant]

Just as I read about advances in solar energy (and more efficient, multiple layered panels)

There are tandem junctions on the market, like Sharp Micromorph a tandem of 2 thin film cells. However the Chinese are turning out crystalline (ie non thin film) cells so cheaply that the economics of think film are less attractive, especially given thin film generally have generally lower efficiency & faster ageing. Aside from all this, whatever technology is used, there will always be a much stronger business case to put them where they get the most sun, i.e on south facing roofs.

Now consider that a 20km branch would cost only ~£30m at most to electrify if single track, and the operational cost benefits that are lost by not electrifying it. (You will never be able to run another kind of electric stock down that route and will have to maintain a microfleet).
EDIT: And I am against IEP bi-mode as well, since the money could have brought in every electrification team in western europe. I am not entirely sure how removing the need to do electrification of any branch lines at all will bring about economies of scale. IEP bi-mode has essentially killed any possibility that the CrossCountry route will actually be electrified any time in the next 30 years.

I think HSTEd has hit the nail on the head.
There is this tendency to assume that because an idea is new and hi-tech it is necessarily better, when often it isn't, hyperloop anyone..?

Even if this idea did have a robust business case (which doesn't sound likely), our fundamental problem in the UK is that we always get these things to proof of concept stage then get cold feet before any commercial return can be made. Tilting trains and large wind turbines are good examples of technologies developed in the UK but commercialised elsewhere in Europe.

 

[D365]

You mean like the larger Parry People Mover designs?

Didn't catch on unfortunately.

Super-capacitors are the way forward, particularly if new materials are developed to improve their performance in the near future.

Wouldn't like to have one of those blow up D:

If a 379 is to be pinched for testing, remembering that GA seemed reluctant to let go of one for 110mph development (for the Southern '377/8' 116+140), would it be possible to run both projects on the same unit, though not at the same time.

 

[broadgage]

I dont see why the 379 used for testing cant also be used in revenue service in the peaks.
I doubt they want to risk useing it in battery mode until thoroughly tested, but presumably it can be used in standard electric mode if needed ?

 

[D365]

I dont see why the 379 used for testing cant also be used in revenue service in the peaks.
I doubt they want to risk useing it in battery mode until thoroughly tested, but presumably it can be used in standard electric mode if needed ?

Depends how far away it will be and whether it will remain in a suitable state for use..!

 

[joeykins82]

I am against IEP bi-mode as well, since the money could have brought in every electrification team in western europe.
I am not entirely sure how removing the need to do electrification of any branch lines at all will bring about economies of scale.
IEP bi-mode has essentially killed any possibility that the CrossCountry route will actually be electrified any time in the next 30 years.

A replacement intercity stock programme would've happened with or without the bi-mode spec, and the bi-mode development is only a small part of the overall cost. A rolling electrification programme (like the one that's underway) makes more sense to the long term economy of the country than pulling in european teams; it provides skilled jobs with 30 years of stability.

 

[jon0844]

As I see it, even though this stock will be bi-mode, everyone wants to switch them to electric only as soon as possible - not just say 'hey, we can stop the electrification projects now'.