UK Electric Buses

[GardenRail]

After going to Rotterdam and Amsterdam, including a few other European Cities, I have noticed that a lot of their electric buses have a pantograph on the roof, which they raise at certain bus stops on to a contact bar. I presume this is to charge the battery. This seems like a good heavy infrastructure, and not done on the cheap.

I have also noticed that here in the UK, electric buses are getting more in number, but without the extensive infrastructure such as above.

Why have we chosen the (what appears to be) cheaper, more naff option? Or is there some benefit that I am missing?

I am not into buses, but can't pretend to be unimpressed by the buses with a pantograph as a way of charging, which is surely the good way to do electric, and buses? Surely this could be introduced in the UK, on urban routes and their associated termini? Small Towns, Big Cities.....

 

[Farigiraf]

Many cities in the UK used to have trolleybuses but they were replaced with cheaper diesel buses. I heard rumours of the Cambridgeshire Guided Busway being eventually trolleybus-operated but I don't see this happening. Maybe it's time to go back to them as a greener alternative?

https://en.wikipedia.org/wiki/List_of_trolleybus_systems_in_the_United_Kingdom

 

[ANDREW_D_WEBB]

TfL route uses this system at Bexleyheath garage for route 132. Route 358 will get Irizar electric buses when the pantographs chargers get operational at Orpington and Crystal Palace bus stations.

Harrogate bus station also uses this system for top up charging on Transdev routes

 

[joieman]

Many cities in the UK used to have trolleybuses but they were replaced with cheaper diesel buses. I heard rumours of the Cambridgeshire Guided Busway being eventually trolleybus-operated but I don't see this happening. Maybe it's time to go back to them as a greener alternative?

https://en.wikipedia.org/wiki/List_of_trolleybus_systems_in_the_United_Kingdom

There are some distinct advantages of trolleybuses to battery-powered buses as well as to trams that I can see. Firstly, batteries onboard could easily get away with being much smaller, saving weight and therefore energy over a battery-powered bus. However, since they do not run on rails, they can also divert to avoid blockades, and the battery, though reduced in capacity, would be sufficient to traverse the diversion route, whereas tram services often require replacement buses if a part of the tramway is closed for repairs.
They make most sense on high-frequency service corridors, and where the frequency of a bus service is insufficient to warrant overhead wires, they could, once again, run under battery power until returning to overhead wires. Lastly, since guided busways also require high-frequency services to be economical, I believe guided busways with overhead wires would be an excellent combination.

 

[JamesT]

Possibly there’s a difference in how these European cities use their fleets of buses?
Oxford is gaining electric buses, but both companies have had chargers put in at their depots. The implication being each bus can do a complete day’s work before charging overnight. This has involved investment, OBC basically have a substation in their depot to support 104 chargers, but it’s not out on the street.

 

[HST43257]

Happens in Harrogate, from memory on the routes 2, 3 and 6. They all charge up using their pantographs at the Harrogate Bus Station right next to the rail station and it’s fascinating to watch.

 

[ClydeCoaster]

Kilmarnock bus station has pantographs to charge Stagecoach West Scotland's fleet of Volvo 7900e buses operating route 1 to Priestland.

I'm not sure why pantograph charging isn't catching on in the UK, I'm guessing because of the infrastructure costs and of course, the need to tie up with local authorities etc. as, outwith bus stations, they'd need to be situated at terminuses, often in town/village centres or housing estates.

 

[AndrewE]

Kilmarnock bus station has pantographs to charge Stagecoach West Scotland's fleet of Volvo 7900e buses operating route 1 to Priestland.

I'm not sure why pantograph charging isn't catching on in the UK, I'm guessing because of the infrastructure costs and of course, the need to tie up with local authorities etc. as, outwith bus stations, they'd need to be situated at terminuses, often in town/village centres or housing estates.

not necessarily, we saw this on Seville trams last week:

 

[stevieinselby]

I'm not sure why pantograph charging isn't catching on in the UK, I'm guessing because of the infrastructure costs and of course, the need to tie up with local authorities etc. as, outwith bus stations, they'd need to be situated at terminuses, often in town/village centres or housing estates.

I guess the logistics can be difficult. It works in Harrogate because the local routes that use electric buses only ever use single-deckers, they can be accommodated in 2 stands at the bus station (each one seeing 4 or 5 buses per hour) and the bus station is owned by the bus company and not the council. Where there may be a mix of single and double deckers, or where routes don't serve a bus station on dedicated stands seeing a good number of departures, it may be more difficult. For example, in York where there is no bus station, or in Leeds where many city services don't call at the bus station, it's harder to envisage where pantograph charging could be installed. Perhaps with the increasing range of electric buses, it is not seen as a priority.

 

[AndrewE]

I guess the logistics can be difficult. It works in Harrogate because the local routes that use electric buses only ever use single-deckers, they can be accommodated in 2 stands at the bus station (each one seeing 4 or 5 buses per hour) and the bus station is owned by the bus company and not the council. Where there may be a mix of single and double deckers, or where routes don't serve a bus station on dedicated stands seeing a good number of departures, it may be more difficult. For example, in York where there is no bus station, or in Leeds where many city services don't call at the bus station, it's harder to envisage where pantograph charging could be installed. Perhaps with the increasing range of electric buses, it is not seen as a priority.

I think that with modern control systems (video cameras, software-driven contact positioning kit) it should be possible to park a bus roughly in a bay and the box containing the 2 contacts would lower as far as needed while the clever machine adjusts the side- and fore-and-aft positions.
I guess you would want the pan in the same place relative to the front of the bus on different models, and recharging both single and double-deckers might be too much of an ask...

 

[JamesT]

I guess the question is, assuming you have sufficient battery capacity to run all day, what advantages does a pantograph give over plugging in with a cable overnight?

 

[stevieinselby]

I think that with modern control systems (video cameras, software-driven contact positioning kit) it should be possible to park a bus roughly in a bay and the box containing the 2 contacts would lower as far as needed while the clever machine adjusts the side- and fore-and-aft positions.
I guess you would want the pan in the same place relative to the front of the bus on different models, and recharging both single and double-deckers might be too much of an ask...

I'm not sure I would want that kind of charging equipment in an unrestricted public place though ... in a bus station is very different to a roadside bay.

 

[GusB]

I guess the question is, assuming you have sufficient battery capacity to run all day, what advantages does a pantograph give over plugging in with a cable overnight?

Removal of a trip hazard is one advantage I can think of.

 

[stuu]

not necessarily, we saw this on Seville trams last week:

Those trams in Seville use capacitors rather than batteries, they have a very short recharge time (and very short range)

 

[AndrewE]

I'm not sure I would want that kind of charging equipment in an unrestricted public place though ... in a bus station is very different to a roadside bay.

but it lowers itself from above the roadway down onto the bus

Removal of a trip hazard is one advantage I can think of.

and the need to manually make a high-voltage high-current connection. The Helsingor-Helsingborg ferries have a robot arm to do it.

 

[ClydeCoaster]

I guess the question is, assuming you have sufficient battery capacity to run all day, what advantages does a pantograph give over plugging in with a cable overnight?

Also reduces the weight of the vehicle itself as it doesn't need the heavy battery capacity required for all day running if opportunity (pantograph) charging can be deployed.

 

[AndrewE]

Those trams in Seville use capacitors rather than batteries, they have a very short recharge time (and very short range)

OK, maybe that's a niche application then. However the way technology is developing I wouldn't rule out the boffins developing a hybrid of the two, or some other way of dealing with the difficult opposite of the sweet spot where neither performs best.
Milan buses apparently do fast charging https://www.sustainable-bus.com/electric-bus/fast-charging-station-electric-buses-atm-milano/ and there's no mention of capacitors, just batteries in the linked articles.

I guess the question is, assuming you have sufficient battery capacity to run all day, what advantages does a pantograph give over plugging in with a cable overnight?

I imagine the benefit is you only need half as much battery per bus in the first place, plus the other benefits above.

 

[Teapot42]

OK, maybe that's a niche application then. However the way technology is developing I wouldn't rule out the boffins developing a hybrid of the two, or some other way of dealing with the difficult opposite of the sweet spot where neither performs best.
Milan buses apparently do fast charging https://www.sustainable-bus.com/electric-bus/fast-charging-station-electric-buses-atm-milano/ and there's no mention of capacitors, just batteries in the linked articles.

I imagine the benefit is you only need half as much battery per bus in the first place, plus the other benefits above.

Not sure if it's been commercialised, but battery + supercap has been looked at in the past.

One issue with moving to a smaller battery is that the maximum current you can draw from a battery is a factor of capacity. You can get high discharge cells, but they cost more. Similarly with fast charging, cells which can accept a fast charge cost more and degrade quicker.

This is where the supercaps come in, they can supply and absorb energy much quicker than a battery with very little impact on life. Adding a supercap to a small battery means the high current needed for initial acceleration can come from the capacitor, and high regen currents are absorbed by it. This protects the battery and potentially allows more cost effective charging circuitry if it doesn't need to deal with high currents.

I know a while back that flywheels were being looked at as another option. These would be 'charged' by being accelerated by a large fixed motor at special bus stops. Williams F1 set up a division looking at the tech but I'm not sure if it was ever commercialised.