Roger Bryant:

If you were managing a bus company that has to make a profit to survive and supply a service to tempt people to use it rather than the alternatives how would your thinking go? Would you demand government (taxpayer's) subsidies? Would you, like the Germans, choose to use expensive electricity that frequently comes from dirty fossil fuel sources (brown coal) to support your virtue signaling?

 

To be honest, if I were running a commercial bus company now, I would still be buying diesel buses.  But it's a fast changing market, so things may be different in 5 year's time, and will certainly be different in 15 years' time.  There will be a point, not too far in the future, when it stops being virtue signalling and starts being abandoning an obsolete technology.


If I were running a public transport system for a city, I might try buying (or leasing) a few electric buses to see how well they work.  My priorities would be different to someone running a commercial outfit.  City centre pollution would be my problem, not somebody else's.


When I was in Nottingham a couple of weeks back, I was very impressed with their electric trams, and how well they went up quite steep hills, in a way that normal trains don't.

Simon Barker:

 

Luciano Bacco:

Could this new British single-seater pod 'transform future mobility'?

https://www.imeche.org/news/news-article/could-this-new-british-single-seater-pod-'transform-future-mobility


 

 

So somebody has just produced a brand new vehicle that's just like a Renault Twizy, except with one less seat.  The Twizy was first launched in 2012, and you can buy one from your local Renault dealer now.

 

 

I had a play in a Twizzy at our 'Environment' Arena (this was actual at the IET Switzerland AGM).
https://www.umweltarena.ch/besuchen/testfahrten

My wife was initially skeptical about the space in the back but found it ok. I also had a go on a Segway, hard to start and stop but okay when going along, and one of the electric delivery trikes that the Swiss Post uses. This had regenerative braking in the first part of the twist grip movement which combined with the instability of a three wheeler under braking caused a couple of anxious moments.


Best regards


Roger

mapj1:

 

Where does the electricity come from? If it is from burning fossil fuels I should probably stick with diesel buses

Not so simple. Firstly I may be trying to clean the air in the city, but less worried about the pollution from the power station.

Secondly, a diesel bus will not allow regenerative braking, and the engine runs even when you are stopped at the bus stop or in traffic (at least in older buses).

Consider this  very modern 7900 electric volvo bus

an 8 hour day of perhaps 150-200km on a full  charge.

or this
diesel figures, same manufacturer    this sort of  thing, perhaps 30 litres per 100km.


Looks like a winner - 30 litres for one hour only is 140kVA genset (  ish  -   link)

And electricity generation is a touch more efficient that a diesel genset in a proper power station.

And a lot better if like the UK we have some nuclear and some wind generation to throw in the mix.



So how far can we go on a 140 kVA battery?

usual caveats

so more like 100 to 200km in reality then.

Not clear that the electric option is worse, it may be better, even just as it is.

I'd be the first to agree there have been some noticable cock ups  on early systems 

example the Albuquerque Rapid Transit   but I suggest that shows the technology is immature, not impossible

(battery temperature control was a large part of the failure of that pilot, and the longer range per day required compared to a typical

European city bus route.)


 

 

Some interesting information  ?  If air quality is part of the requirement than gas is also a fairly good option. The exhaust is probably subjectively cleaner than a Euro 6 diesel. Gas powered fork lift trucks have been used in factories for years. If your electricity is generated at Aberthaw you probably get the 'benefit' of it's pollution in Bristol if the wind is in the right (wrong) direction.


The range/energy consumption figures are interesting but as you say the usual caveats apply. Some semi random thoughts:


Volvo 7900 bus- I guess the 19kWh battery is a typo although as they are offering roof mounted charging rails (OppCharge) maybe not. From the other information it may be 190kWh but the voltage and hence the energy storage are not given. It could be anywhere between 400 and 750V.


It offers 'Ramp heating' so you can pre heat the bus in cold weather from a fixed supply to reduce the demand on the battery. 'Hotel' load is not so much of a problem in the UK but in other lands where you have to maintain the saloon at a reasonable temperature when the outside temp can be between -20°C and 40°C is a significant load. The battery temperature will also have to be controlled. My Smart would never really warm up at town speeds in sub zero temps. The diesel version had an additional electric heater powered by the alternator as the engine delivered even less waste heat. My present diesel Touran has an additional Webasto heater to deal with the problem of a fairly large cabin and a lack of waste heat from the engine.


The consumption figures for the diesel powered buses appear to be real world, including idling time and heating and aircon loads. It is not completely clear if the figures are just for longer distance coaches or city buses? 30L of diesel will run your bus for 100km or generate 140 kWh at 400V 3 phase in a genset. Will an electric bus cover an equivalent 100km of service on 140 kWh (assuming a 400V battery)? If they are using OppCharge ( https://www.oppcharge.org/  ) The real range per charge may be much less. The data from Volvo suggests a working range up to 200km. This is probably with the largest 250kWh battery and minimal heating and aircon loading. Are they also allowing for OppCharge? Guesstrapolating suggests that in the real world it will be possible but with a lot of caveats.


As I have said before I live in an ideal public transport part of the world. The electric trains, trams and trolley buses are powered by hydroelectricity with a bit of nuclear in the background. We live over a shopping complex so we can just push the trolley from the cash desk to the lift and then into the kitchen. The railway station is 5 minutes walk with a very regular service to Zürich. The car is rarely used, generally when supporting our daughter and grandchildren, and may well be got rid of in the near to middle future.


Best regards


Roger

A couple of interesting pieces from E&T.


The first on the problems of using EVs in cold weather:

https://eandt.theiet.org/content/articles/2020/02/how-to-stop-cold-weather-decimating-the-range-of-your-electric-vehicle/


Both pre-conditioning and smart charging assume that you have your own dedicated charging point.


The second is on recycling EV batteries:


"That high level of risk continues into the decommissioning phase, but is reduced as the packs are broken down to a modular level where voltages are much lower; it’s a safer prospect to work with 20 30V modules than a single 600V battery.

However, the reverse logistics of breaking down an electric battery are complex. At present it involves a specially trained technician wearing specific arc-flash-proof protective clothing and using insulated tooling. Risk assessment and method statements make the process as safe as it can be, but even with such protocols the danger of fire and electrocution is very real. Away from these obvious hazards, the handling of a battery that can weigh more than 600kg mass is awkward and sometimes easier said than done, especially when it is heavily damaged with componentry fusing together after a heat event."

https://eandt.theiet.org/content/articles/2020/02/recycling-industry-is-on-course-to-prove-pessimism-of-ev-waste-warnings/


Best regards


Roger