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All across the Great Western territory => The Wider Picture Overseas => Topic started by: NickF on August 12, 2014, 11:07:14 am



Title: Siemens powers trucks like trams with overhead wires
Post by: NickF on August 12, 2014, 11:07:14 am
http://www.wired.co.uk/news/archive/2014-08/11/siemens-ehighway-tests


Title: Re: Siemens powers trucks like trams with overhead wires
Post by: trainer on August 12, 2014, 03:56:21 pm
I think the trolley bus is a nearer comparison for overhead electric power for a road vehicle.  The catenary looks very heavy-weight and not at all like the less obtrusive power lines used for trams and trollies.  Can't see it catching on in narrow, historically sensitive streets.

Thanks for an interesting link, Nick.


Title: Re: Siemens powers trucks like trams with overhead wires
Post by: stuving on August 12, 2014, 04:17:32 pm
Can't see it catching on in narrow, historically sensitive streets.

Surely that's not the idea? I think it's aimed at motorways, as part of a "what do we do if there's no oil left" plan B.

What is neat is to make use of in-road (presumably) guidance to keep the truck under the wires, so you no longer need to hook a "trolley" onto a wire.  A modest supercapacitor/battery allows you to change lanes or park. You could also make the supply three phase, if you wanted (e.g. you are Swiss).


Title: Re: Siemens powers trucks like trams with overhead wires
Post by: eightf48544 on August 12, 2014, 04:43:18 pm
I presumme the heavy weight wires and pans are to be able to pass the necessary Watts to a number of trucks simultaneously.

Was there any mention of the voltage?

Agree it's more like a trolley bus than a tram but it's funny how things keep getting reinvented.

Wonder if you can fit regen brakes?



Title: Re: Siemens powers trucks like trams with overhead wires
Post by: stuving on August 12, 2014, 06:53:30 pm
Was there any mention of the voltage?
650V DC
Quote
Wonder if you can fit regen brakes?
Yes.

As well as being a Siemens project, it has been part of a German government research project called ENUBA, followed by ENUBA-2. However, most of the material available (and almost all that is in English) is from Siemens.

They don't actually mention guidance, but do go on about clever adaptive pantographs. So I guess at this stage if you drive off line the pan drops - which you'd need to do anyway, even guided, and it saves coupling it to another research project.


Title: Re: Siemens powers trucks like trams with overhead wires
Post by: Rhydgaled on August 12, 2014, 08:08:19 pm
Can't see it catching on in narrow, historically sensitive streets.
Surely that's not the idea? I think it's aimed at motorways, as part of a "what do we do if there's no oil left" plan B.

What is neat is to make use of in-road (presumably) guidance to keep the truck under the wires, so you no longer need to hook a "trolley" onto a wire.  A modest supercapacitor/battery allows you to change lanes or park. You could also make the supply three phase, if you wanted (e.g. you are Swiss).
Of course one of the advantages of rail electrification is the weight reduction from not having to carry self-power equipment (a benifit which is thrown away by the likes of the class 800/801) and hence a reduction in the amount of energy needed to shift the thing.


Title: Re: Siemens powers trucks like trams with overhead wires
Post by: stuving on August 12, 2014, 08:21:35 pm
Of course one of the advantages of rail electrification is the weight reduction from not having to carry self-power equipment (a benifit which is thrown away by the likes of the class 800/801) and hence a reduction in the amount of energy needed to shift the thing.

Not only is the current demo system a hybrid, but there is no visible plan to drop the diesel engine. I think the reason is obvious - you will need it until the wires cover the great majority of point-point truck runs. That could be a very long wait...

The choice of 650V DC is, I would guess, to avoid excess weight in transformers etc.


Title: Re: Siemens powers trucks like trams with overhead wires
Post by: Rhydgaled on August 12, 2014, 08:48:14 pm
Of course one of the advantages of rail electrification is the weight reduction from not having to carry self-power equipment (a benifit which is thrown away by the likes of the class 800/801) and hence a reduction in the amount of energy needed to shift the thing.

Not only is the current demo system a hybrid, but there is no visible plan to drop the diesel engine. I think the reason is obvious - you will need it until the wires cover the great majority of point-point truck runs. That could be a very long wait...

The choice of 650V DC is, I would guess, to avoid excess weight in transformers etc.
Of course you could detatch the trailer/container from the diesel power unit and put it behind an electric 'locomotive'.


Title: Re: Siemens powers trucks like trams with overhead wires
Post by: bignosemac on August 12, 2014, 10:11:36 pm
So a potential two power units for each trailer? And associated additional cost for marshaling yards/staff/time to effect the switch over.

Or stick with the designed single unit hybrid solution.


Title: Re: Siemens powers trucks like trams with overhead wires
Post by: broadgage on August 14, 2014, 12:46:17 pm
Electrically powering a rubber tyred vehicle is inherently more complex than a tram or electric train.
A rubber tyred vehicle needs TWO overhead wires and TWO pantographs, unlike a rail vehicle or tram that needs only one, with return via the rails.
Having gone to expense of installing the infrastructure, then of course a trolley bus service on the same route might be viable.


Title: Re: Siemens powers trucks like trams with overhead wires
Post by: stuving on August 14, 2014, 01:10:56 pm
Do remember this is research. They seem to be proposing the pictured system, as tried out on a test track in Germany, for the demo in California. However, I'd guess it might change a bit as it is further developed for that.

And I'm sure they have looked a lot of other possibilities, which may become preferable in the many years before any large-scale adoption. Once the truck knows where it is in the road, and has a battery or other energy store to take it even a few tens of metres, and the pantograph is moderately clever, all sorts of things are feasible.

For example, you simply stop the overhead supply at junction and rely on that energy store. Then you could put the two conductors side by side and clasp it with two collectors on a single arm. Or all sorts of other alternatives.


Title: Re: Siemens powers trucks like trams with overhead wires
Post by: Oxonhutch on August 14, 2014, 01:28:57 pm
Many open pit metal mines use these vehicles for rock haulage out of the (often quite deep) mines using electric on the incline and switching over to conventional diesel on the level pieces - both in and out of the pit.

Click here (http://www.pythongroup.ca/mining-news/article/id/35) for an article on such vehicles.  From personal observation (on the job), as soon as these trucks hit the electric juice, they speed up tremendously.  Very impressive in their scale too - the tyre height alone towers above a man.  Then there is the wheel hub, the top of the tyre and then the rest of the truck.  Hybrid monsters indeed.


Title: Re: Siemens powers trucks like trams with overhead wires
Post by: stuving on September 21, 2017, 11:06:32 am
Siemens have been busy on this project in the years since the earlier news items posted above, and have had two trucks doing trials in Sweden for a year, on a 2km stretch of public road. They just announced a bigger trial in Germany (https://www.siemens.com/press/en/feature/2015/mobility/2015-06-ehighway.php#event-toc-2):
Quote
Siemens has been commissioned by the German state of Hesse to build an overhead contact line for electrified freight transport on a ten-kilometer stretch of autobahn. The line will supply electricity for the electric drive of a hybrid truck. Siemens originally presented its innovative "eHighway" concept in 2012. The system will be installed on the A5 federal autobahn between the Zeppelinheim/Cargo City Süd interchange at the Frankfurt Airport and the Darmstadt/Weiterstadt interchange.

The words all refer to the trucks as being hybrids, with diesel power as the other source not batteries. And as to what's happened to the proposed trial in California; I can still only see it mentioned in the future tense.


Title: Re: Siemens powers trucks like trams with overhead wires
Post by: Bmblbzzz on September 21, 2017, 11:56:45 am
Interesting idea.

Clearly it's more similar to a trolleybus than a tram but it has a railway-like pantograph. Presumably this is to allow overtaking, as the article says, and I'd imagine it also makes the connectors less likely to lose contact going over bumps and potholes.

I think it could be a useful step on the way to electric HGVs, which are going to be much more difficult than electric (or fuel cell!) cars due to the longer distances and greater unpredictability of refuelling spots. Though of course a regular port run involves one known recharging spot every time; but still there would be the downtime cost of recharging, unless it can be included in driver's rest. OTOH it could turn out to be a great white elephant due to cost of OHLE.


Title: Re: Siemens powers trucks like trams with overhead wires
Post by: broadgage on September 21, 2017, 01:08:21 pm
This idea has its merits but is not so new as may be supposed. Electric road vehicles powered from an overhead were used about 100 years ago.
IIRC the goods were placed in standard wagons primarily intended for horse hauling, but were hauled electrically up hills in particular.
I cant find the link but it was on a site about old technology.

Electrically powered canal boats were also tried.


Title: Re: Siemens powers trucks like trams with overhead wires
Post by: broadgage on September 22, 2017, 03:19:17 pm
This is how it was done, a century ago.http://www.lowtechmagazine.com/2009/07/electric-road-trains-in-germany-1901-1950.html (http://www.lowtechmagazine.com/2009/07/electric-road-trains-in-germany-1901-1950.html)


Title: Re: Siemens powers trucks like trams with overhead wires
Post by: Bmblbzzz on September 22, 2017, 07:38:59 pm
Those are more like conventional trolley buses as used today, at least in their current pick-up arrangements. The ones combining electric power with horses are interesting – an early hybrid system!


Title: Re: Siemens powers trucks like trams with overhead wires
Post by: stuving on April 17, 2018, 11:11:58 am
Here's some competition for Siemens from a bunch of Swedes  (https://eroadarlanda.com/globally-unique-electrified-road-enables-fossil-free-road-transport/)- using ground pick-up (https://inhabitat.com/worlds-first-electric-road-that-charges-moving-vehicles-debuts-in-sweden/). Very much a demonstration activity at the moment, with only one vehicle and the 1.2 km of road conveniently close to Stockholm Arlanda airport. The idea is keep an all-electric vehicle's battery charged up so it can do short trips away from main roads (https://www.energylivenews.com/2018/04/13/sparks-fly-in-sweden-with-new-electric-road/) (this from Energy Live News):
Quote
(https://www.energylivenews.com/wp-content/uploads/2018/04/electric-truck_.jpg)

The world’s first road able to directly charge electric vehicles (EVs) has officially opened in Sweden.

Around 1.2 miles of electric rail has been embedded in a public road near Stockholm – it aims to solve the problem of having to keep electric vehicles charged up and is expected to enable EVs to use smaller batteries, reducing costs.

It works by using a movable arm attached to the bottom of a vehicle to receive energy from two tracks of rail in the road, much like a Scalextric track.

The infrastructure costs around €1 million (£860,000) per kilometre and calculates vehicles’ energy consumption, enabling electricity costs to be debited per vehicle and user.

Both current vehicles and roadways could be adapted to take advantage of the technology.

Hans Säll, CEO of the eRoadArlanda consortium behind the project, said: “If we electrify 20,000 kilometres of highways that will definitely be enough.

“The distance between two highways is never more than 45 kilometres and electric cars can already travel that distance without needing to be recharged. Some believe it would be enough to electrify 5,000 kilometres.”

This is all very reminiscent of trams, which had three main systems of feeding - overhead (trolley), underground (conduit), and switched surface contact. In the end overhead was cheaper to build and maintain, partly because of the dirt and water than hangs about at ground level, and partly because the rails get in the way of any continuous power feed in the ground. For these new ones, with no rails, that second point isn't an issue, and if water/ice/snow cause problems then the Swedes should find out soon enough.


Title: Re: Siemens powers trucks like trams with overhead wires
Post by: eXPassenger on April 17, 2018, 11:25:07 am
There is no comment on the voltage or overall power draw.  I imagine the voltage will be fairly low for safety reasons - even on a motorway there can be pedestrians and animals; and I hate to think of the required current if there is a convoy of HGVs.

On the other hand real life Scalextrix with racing trucks would be a blast,


Title: Re: Siemens powers trucks like trams with overhead wires
Post by: stuving on April 17, 2018, 11:47:50 am
There is no comment on the voltage or overall power draw.  I imagine the voltage will be fairly low for safety reasons - even on a motorway there can be pedestrians and animals; and I hate to think of the required current if there is a convoy of HGVs.

On the other hand real life Scalextrix with racing trucks would be a blast,

In one article it says 200 kW - in which case either the volts, or the amps, or even both, must be worryingly high to keep in a hole in the road.


Title: Re: Siemens powers trucks like trams with overhead wires
Post by: mjones on April 17, 2018, 01:11:24 pm
I understand that the power rail voltage is 750V, but the rail is built in short sections that are electrified only when a vehicle is passing, greatly reducing the risk to other road users.

It is an Alstom system based on a similar system already used for trams.
http://itsworldcongress2017.org/wp-content/uploads/2017/11/Duprat.pdf


I also found this useful review which discusses different electric road technologies.
http://www.diva-portal.org/smash/get/diva2:1046753/FULLTEXT01.pdf


Title: Re: Siemens powers trucks like trams with overhead wires
Post by: stuving on April 17, 2018, 01:34:40 pm
I understand that the power rail voltage is 750V, but the rail is built in short sections that are electrified only when a vehicle is passing, greatly reducing the risk to other road users.

It is an Alstom system based on a similar system already used for trams.
http://itsworldcongress2017.org/wp-content/uploads/2017/11/Duprat.pdf


I also found this useful review which discusses different electric road technologies.
http://www.diva-portal.org/smash/get/diva2:1046753/FULLTEXT01.pdf


There are two Swedish ground pickup designs - one based on Alstom's tram system (cf. Bordeaux), with Volvo's trucks and at their test track, and the Arlanda one using the Elways conduit and a DAF truck on a public road. Both only switch on the power to short sections on demand, and need complicated feeding arrangement along the road to supply that efficiently. The Elways one is 800 VAC, rather than 750 VDC.


Title: Re: Siemens powers trucks like trams with overhead wires
Post by: martyjon on April 17, 2018, 03:56:41 pm
Take a look at this ;-

https://f1.media.brightcove.com/12/1813624294001/1813624294001_5537341264001_5537335049001.mp4?pubId=1813624294001&videoId=5537335049001


Title: Re: Siemens powers trucks like trams with overhead wires
Post by: stuving on August 08, 2021, 05:08:40 pm
This Siemens eHighway is still advancing, if only by baby steps. The German federal government is making encouraging noises, but Siemens have only just opened the third trail road systems and that (between Kuppenheim and Gaggenau) is only about 5 km long!

But today's Sunday Times was reporting that they had been putting a concrete proposal to our government, and it was in other papers last month when Innovate UK let a study contract to a consortium including Siemens. It's not clear how or if this fits into Innovate UK's routine grants competitions, and it may be separate (money from DfT direct but adminstered by IUK).

it was announced from DfT (https://www.gov.uk/government/news/road-freight-goes-green-with-20-million-funding-boost), and also by consortium leader Costain (https://www.costain.com/news/news-releases/green-light-for-path-to-uk-s-first-electric-motorway/):
Quote
Green light for path to UK’s first ‘electric motorway’
27 July 2021

• Through Innovate UK, the Department for Transport has commissioned a Costain led consortium to assess the economic and technical potential of the UK’s first ‘eHighway’

• The study is part of the UK government’s plan to reach zero net emissions for heavy road freight

• It aims to demonstrate the technology is ready for a national roll-out

The Department for Transport has awarded funding through Innovate UK to a consortium to lead the UK’s first ever study on the electrification of long-range trucks with dynamic charging, using overhead wires on motorways.   

The study is part of the £20m put aside for zero emission road freight trials under the recently announced Transport Decarbonisation Plan (TDP) and was awarded based on the Costain led consortium expertise in sustainable transport. It includes Siemens Mobility, Scania, The Centre for Sustainable Road Freight (Cambridge University and Heriot-Watt University), ARUP, Milne Research, SPL Powerlines, CI Planning, BOX ENERGI and Possible.
...
The consortium has proposed an ‘electric road system’, using the Siemens Mobility ‘eHighway’ technology, as the fastest, lowest carbon and most cost-effective route to decarbonising our road freight industry and delivering cleaner air. The nine-month study kicks off this month and is hoped to be the forerunner of a scheme that aims to see the UK’s major roads served by overhead lines by the 2030s. These eHighways allow specially adapted trucks to attach to the overhead wires and run using the electricity, like rail and trolley-bus systems. The trucks come equipped with a battery that charges while they are in motion so they can detach to both overtake vehicles and reach their destination with zero emissions from start to finish. 

Consortium members Siemens Mobility, Scania and SPL have previously trialled smaller electric road systems in Germany and Sweden, with this UK initiative being the first in the world to investigate deploying it at a much larger scale. The project will look at electrifying at least 30km (19 miles) of the M180 as the pilot, linking Immingham Port with the logistics hubs of Doncaster and its airport. The partners plan to take the lessons learned from Europe, and provide technical, economic, and environmental recommendations for installing a proof-of-concept system with a bigger demonstration fleet. 

A fully operational electric road system across the UK would be expected to create tens of thousands of jobs across a range of green industries, with around 200,000 new electric trucks needing to be built over a 10–15-year period. This will also provide an opportunity to completely revamp the UK truck manufacturing industry and its supply chains, futureproofing it by accelerating fleet digitalisation; a key lesson learned across the industry as it recovers from the 2020 pandemic’s disruption. 

Research by the consortium has even found that initial investments into new vehicles by operators could be recouped within 18 months, due to lower energy costs, and the electrification infrastructure would pay back investors in 15 years. ...

There other things from Innovate UK too: a load of other grants (https://www.gov.uk/government/publications/innovate-uk-funding-competition-winners-2021), including some on rail (FOAK 2021), and their take on how transport needs to change, UK Transport Vision 2050 (https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/1008833/IUK-050821-4293_Innovate_Future_Transport_A4Portrait.pdf).


Title: Re: Siemens powers trucks like trams with overhead wires
Post by: broadgage on August 09, 2021, 08:42:15 pm
Even with safety precautions, I remain very doubtful about anything involving a lethal voltage at low level. Conductor rail powered railways are bad enough, but on public roads ! it seems unlikely. And of course a vehicle powered by any form of conductor rail needs very accurate steering, presumably automatic.

Overhead wires seem more sensible, after all trolley buses used this system for many years. A vehicle powered thus can be steered as normal, within certain limits. The main drawback of trolley bus type power supply is de-wirement. Historically when this occurred, the driver had to leave the cab and replace the current collectors on the wires, generally by pulling on strings or by use of a long bamboo pole carried for the purpose. These days it can be automated.

BTW, lighting on trolley buses is an old example of a restrictive practice to keep up profits. The lights were supplied via a motor generator set at a safe reduced voltage. 35 volts was used, not used for anything else and thereby ensuring ongoing sales of special 35 volt lamps.


Title: Re: Siemens powers trucks like trams with overhead wires
Post by: Reading General on August 09, 2021, 09:16:51 pm
Modern trolleybuses only tend to de-wire through driver error rather than equipment fault, not setting direction properly or moving too quickly through a junction. Upon dewirement, on some vehicles the poles on top of the vehicle can immediately drop to the roof to avoid damaging overhead. Indeed many dewirement photos I’ve seen on the Reading system appeared to be wrong route set at a junction, meaning the driver was on or off power at wrong moment when passing through the switch.


Title: Re: Siemens powers trucks like trams with overhead wires
Post by: stuving on August 09, 2021, 10:16:01 pm
The Siemens system being proposed uses two small pantographs, so even with the wires spaced well out towards the sides of the vehicle it will need to keep station in its lane. Of course that's not a big deal these days, with or without a driver doing something. If there's any problem with that, or at each end of the wired bit and at junctions if there are any, the pans drop and traction relies on batteries (or supercapacitors). By all accounts it's developed far enough to be worth a proper trial, at least.


Title: Re: Siemens powers trucks like trams with overhead wires
Post by: 4064ReadingAbbey on August 10, 2021, 03:30:21 pm
Attached is a photograph I took (while my wife was driving  :) ) in May 2019 of a test length being constructed on the A1 near Lübeck. The autobahn is normally three lanes but the nearside lane was closed while the wires being put up.

The published idea is to reduce the quantity of diesel fuel being used for goods transport. As Germany is also a transit country which adds to the number of heavy vehicles the road freight traffic levels have to be seen to be believed. By electrifying the trunk haul the idea is to reduce overall emission levels, leaving the HGVs with their diesel engines for off-motorway work and for working around obstructions.

There is no intention - as yet - of putting the wires up on other types of road as the design, planning and installation issues are too great. The advantage of wiring autobahnen is that the road design is consistent and allows a technical solution based on standardised components to be used.



Title: Re: Siemens powers trucks like trams with overhead wires
Post by: broadgage on August 10, 2021, 08:02:40 pm
I am impressed  :)

Although this is a small scale trial, it is an actual installation on an actual public road that remains in use.
A considerable step forward if compared to trials on a dedicated test route, and an even greater step forward over simulations and paper studies.


Title: Re: Siemens powers trucks like trams with overhead wires
Post by: stuving on August 10, 2021, 11:23:15 pm
I am impressed  :)

Although this is a small scale trial, it is an actual installation on an actual public road that remains in use.
A considerable step forward if compared to trials on a dedicated test route, and an even greater step forward over simulations and paper studies.

In some ways that's so - the original post on this thread was in 2014, when the Elisa real-world (or real-road) trials in Germany were imminent. But while the first trail started in June 2016, that was in Sweden (2 km near Stockholm airport), and appears to have been segregated by a wall. The initial installation in Germany, on the A5 near Frankfurt airport, only opened in May 2019, and the second one, on the A1 near Lubeck, in 2020 (both are 10 km long).

And then the third one, as reported above, on the B462 in Baden-Wurtenberg, opened in June 2021. This is not an autobahn, so less straight, though only 3.4 km (see this report for details (https://www.marketscreener.com/quote/stock/SIEMENS-AG-56358595/news/Siemens-Third-eHighway-field-trial-starts-in-Germany-35743703/)). There is also a mile (each way) in Los Angeles, installed in 2017, which I've not heard of since.


Title: Re: Siemens powers trucks like trams with overhead wires
Post by: eightonedee on August 11, 2021, 11:26:25 am
If this is extended to the UK along the same principles, (motorways only), it will miss many of our key freight road haulage routes to and from ports which governments have failed to upgrade to motorway status for decades - the A12, A34 and A14 all immediately come to mind.


Title: Re: Siemens powers trucks like trams with overhead wires
Post by: stuving on August 11, 2021, 11:29:54 am
If this is extended to the UK along the same principles, (motorways only), it will miss many of our key freight road haulage routes to and from ports which governments have failed to upgrade to motorway status for decades - the A12, A34 and A14 all immediately come to mind.

But even in Germany, where the autobahn network is denser than our motorways, the third trial is on a lesser road. So perhaps that's not a principle, more of a good place to start.


Title: Re: Siemens powers trucks like trams with overhead wires
Post by: broadgage on August 11, 2021, 12:28:29 pm
I would prefer to see major ports served by electric railways.
Electrification of roads is more applicable to general freight traffic to/from numerous destinations, rather than intensive flows to ports.
A train carrying dozens of containers will use less energy than dozens of electric trucks, will need fewer staff, and take up less space.

Electric trucks are preferable to diesel on environmental grounds, but electric railways are better still due to reduced friction and greater capacity.


Title: Re: Siemens powers trucks like trams with overhead wires
Post by: eXPassenger on August 11, 2021, 05:49:07 pm
If this is extended to the UK along the same principles, (motorways only), it will miss many of our key freight road haulage routes to and from ports which governments have failed to upgrade to motorway status for decades - the A12, A34 and A14 all immediately come to mind.

I see no reason why A roads that have been widened to dual carriageway standards such as the A34 cannot be electrified, gaps could be left at any roundabouts.


Title: Re: Siemens powers trucks like trams with overhead wires
Post by: mjones on August 11, 2021, 06:09:59 pm
These systems don't need to be continuous,  because the vehicles would be equipped with batteries, and gaps would be expected even on motorways. So there is no particular reason why major A roads would not be equipped.


Title: Re: Siemens powers trucks like trams with overhead wires
Post by: Bmblbzzz on August 11, 2021, 07:46:22 pm
The A roads mentioned do not have motorway status but they do have near-motorway standards. In many countries they would be designated "express roads" or something similar.


Title: Re: Siemens powers trucks like trams with overhead wires
Post by: stuving on August 11, 2021, 07:59:02 pm
The A roads mentioned do not have motorway status but they do have near-motorway standards. In many countries they would be designated "express roads" or something similar.

For trials, like those in Germany and now being studied here, who owns the road might matter in terms of negotiating to do it. But I can't see why the status of the road makes any difference at all in the long run, when there is a legal framework.



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