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Gary Charpentier Send message Joined: 25 Dec 00 Posts: 30734 Credit: 53,134,872 RAC: 32 |
Or, on German Autobahn "Slow" - for many, many km there are no speed limits, and the Germans make full use of that and CRUISE at >200kph The autobahn is constructed for it. A regular road is not. Here there would have been two crimes, reckless driving and street racing. Both felonies. |
Richard Haselgrove Send message Joined: 4 Jul 99 Posts: 14655 Credit: 200,643,578 RAC: 874 |
There's a fascinating article in the current (9 September 2017) edition of New Scientist magazine. I can't quote all three pages, but highlights include: "By 1907, there were almost 1,000 petrol-powered buses in London - more than in Berlin, New York and Paris put together." "The average London bus was ordered off the road every six weeks." (because of their 'appalling noise or noxious fumes') "Newspapers were full of angry letters from the great and the good." (selected example: 'the incessant roar and rattle and pestilential atmosphere and dust diffused by these monstrous vehicles.' Or, at a protest meeting: 'motor buses ought to run underground in main drains, like other nuisances.') Enter - yes, in 1907 - electric buses (trade name: Electrobus). Within days, one of the largest petrol bus companies went bust. And the travelling public loved them - slower, but fume-free, cheaper, and less likely to break down. Trouble is, the buses were fine - they could even exchange the 1.75 tonne batteries in three minutes, to extend range and running time - but the company which ran them was comprised of crooks and share swindlers. They banked £95,000 of investors capital, and scarpered - the buses never ran again. And so the internal combustion engine came back from the dead, and we've been stuck with it ever since. The full story is to be told in a book, "A Most Deliberate Swindle", by Mick Hamer, to be published at the end of the month. Unless that's a fraud as well... Edit - "There's nothing new under the sun": the same story, told ten years earlier. http://www.economist.com/node/9465026 |
zoom3+1=4 Send message Joined: 30 Nov 03 Posts: 65839 Credit: 55,293,173 RAC: 49 |
Electric Buses are back, from the DEAD, in Chicago, neat. The CTA 700 series... http://www.transitchicago.com/electricbus/default.aspx Entered into service in late October 2014, these battery-powered buses provide customers with a cleaner, quieter ride that reduces fuel costs and significantly decreases emissions, which means improved air quality for Chicagoland. The T1 Trust, PRR T1 Class 4-4-4-4 #5550, 1 of America's First HST's |
betreger Send message Joined: 29 Jun 99 Posts: 11365 Credit: 29,581,041 RAC: 66 |
I still have my doubts about all electric vehicles, especially public transport, but it is all green to go that way, and people are clambering on the bandwagon in an attempt to be all with it and trendy. Electric vehicles have fewer moving parts to wear out or be tuned up, so their maintenance costs are far lower. |
rob smith Send message Joined: 7 Mar 03 Posts: 22258 Credit: 416,307,556 RAC: 380 |
Well that's the theory.... In reality it depends on many things other than the number of moving parts - among them being the type of traction motor, the type of inverter, the control system, the type of transmission, the type and configuration of the battery and so on.... Bob Smith Member of Seti PIPPS (Pluto is a Planet Protest Society) Somewhere in the (un)known Universe? |
betreger Send message Joined: 29 Jun 99 Posts: 11365 Credit: 29,581,041 RAC: 66 |
Tesla Model S Hits 300,000 Miles with less than $11,000 maintenance costs. http://www.tesloop.com/blog/2017/8/30/tesla-model-s-hits-300k-miles-with-less-than-11k-maintenance-costs |
Gary Charpentier Send message Joined: 25 Dec 00 Posts: 30734 Credit: 53,134,872 RAC: 32 |
Well that's the theory.... The air conditioning is going to have more moving parts than the rest of the vehicle. Direct drive DC motors and all solid state control. |
rob smith Send message Joined: 7 Mar 03 Posts: 22258 Credit: 416,307,556 RAC: 380 |
Even with "direct drive" there are transmission components in the drive train for example CV joints and bearing, all of which have finite lives, and may require some interventions (planned or unplanned). The DC direct drive only tells you that there is a DC motor driving directly onto drive shaft without a clutch, it does not tell you the presence or absence of a reduction gearbox. There most probable is one as most of these DC motors run at 12,000RPM - a bit more than your average V8's <5,000RPM, and a lot more than the road wheel's few hundred RPM. Of course there are then the variations in "DC" motor - traditional with brushes, rotating field, permanent magnet rotor; some of which do need regular maintenance, some of which are all but maintenance free. So don't just look at the sale brochures, which are gloriously glossy, but look at the technical data that is all too often hidden :-( Bob Smith Member of Seti PIPPS (Pluto is a Planet Protest Society) Somewhere in the (un)known Universe? |
zoom3+1=4 Send message Joined: 30 Nov 03 Posts: 65839 Credit: 55,293,173 RAC: 49 |
Well that's the theory.... I wish the a/c in My car worked fully, maybe one day, I've already put in about $300.00, and I'm thinking to get at the last leak or leaks that are under the dash, might involve another $300.00, I'd hope to be wrong, but it is a Ford dash, that requires special tools and such to remove, and then to reinstall. The last time I had a/c that fully worked, the a/c only lasted maybe 24 hours, back then the place that worked on the car a/c could not work in the car interior, and I've been busy elsewhere, but then there is not enough money chasing too many projects, My friends here understand that, but then anything that I can't do Myself costs money to do. The T1 Trust, PRR T1 Class 4-4-4-4 #5550, 1 of America's First HST's |
rob smith Send message Joined: 7 Mar 03 Posts: 22258 Credit: 416,307,556 RAC: 380 |
The air conditioning is going to have more moving parts than the rest of the vehicle. Direct drive DC motors and all solid state control. Don't make me laugh - modern automotive air-con has only got about three moving parts - direct drive compressor, and two relief valves; or if you count the air side a couple of direct drive fans, a couple of circulation control vents. Bob Smith Member of Seti PIPPS (Pluto is a Planet Protest Society) Somewhere in the (un)known Universe? |
rob smith Send message Joined: 7 Mar 03 Posts: 22258 Credit: 416,307,556 RAC: 380 |
Even with Li-xxx very high charge rates reduces the battery life. In general it would appear that the optimum charge rates are in the region of 3-5 hours, which as you say isn't very good for an intensive public transport system as we see in London. This may be why the Boris Bus is a hybrid not a "pure electric" Bob Smith Member of Seti PIPPS (Pluto is a Planet Protest Society) Somewhere in the (un)known Universe? |
W-K 666 Send message Joined: 18 May 99 Posts: 19135 Credit: 40,757,560 RAC: 67 |
Do individual London bus's run all day? - Unlikely, very inefficient. Or are they like most places where the service is very frequent during rush hour, frequent during middle of the day, infrequent in the evening and the nothing after 10 pm? If as I suspect, then some bus's could run from early morning till noon(ish), another set could run from noon(ish) till end of rush hour and some could just do a split just running during the rush hour and some of the early shift could manage a few hours in the evening and the odd services that run through the night. So where's the problem with electric bus's, with some possibly having to be hybrid's. The one service I know of near here, Mon - Fri, runs ½ hour service from very early morning, 7½ min service through rush hour, 15 min service during day, back to 7½ min service through tea time rush hour then ½ hour service till 10ish. On Fri the service is extended till midnight. |
rob smith Send message Joined: 7 Mar 03 Posts: 22258 Credit: 416,307,556 RAC: 380 |
The vast majority of London buses run all day (~5am to midnight) and run pretty well full for much of the time. Early in the morning its a strange mixture of clubbers returning home and people going to work, then its the morning rush (from about 7am to 10am), then tourists and "grannies" take over until the evening rush, theatre and "out for the evening", finally the last bus home (and of course there are a number of all night buses which are quite entertaining to travel on. London buses really never stop! Bob Smith Member of Seti PIPPS (Pluto is a Planet Protest Society) Somewhere in the (un)known Universe? |
Sirius B Send message Joined: 26 Dec 00 Posts: 24882 Credit: 3,081,182 RAC: 7 |
When it was L.T.E both the buses & trains ran around the same timings. Start at approx. 04:00 & end approx. 01:00. A night service running one an hour would run on the major routes. As route numbers, the buses would run all day. Noting the shift patterns as you stated, an individual bus would run at most 12 hours a day. |
Richard Haselgrove Send message Joined: 4 Jul 99 Posts: 14655 Credit: 200,643,578 RAC: 874 |
Do they recharge the bus, or just the battery? If they could swap batteries in three minutes with 1907 lead-acid technology (I believe a hydraulic lift was involved), surely we could revert to that. I've seen videos of all-electric light aircraft being 'refuelled' by wheeling out a small trolley loaded with replacement battery packs. |
Sirius B Send message Joined: 26 Dec 00 Posts: 24882 Credit: 3,081,182 RAC: 7 |
Where would the replacement batteries be held? I see mileage being quoted. Where London is concerned, mileage is not the problem. An example: - I used to catch the No 38 bus at one end of it's terminals, Clapton Pond to get to WCDO(Royal Mail) approx. 05:20 & get to work approx. 05:50 for a 6am start. At the end of the 2nd delivery which all depended on how much mail I had & where the last delivery was (anywhere from 12:45 to 13:15), the journey home on the same route would be at least an hour & sometimes more. Even outside the rush hours, Central London is congested. |
zoom3+1=4 Send message Joined: 30 Nov 03 Posts: 65839 Credit: 55,293,173 RAC: 49 |
Tesla mentions 5-30 minutes, for its charging, and to forget about swapping, but then Tesla uses Li battery tech, not lead-acid, but then Tesla makes their own batteries now. https://www.technologyreview.com/s/516876/forget-battery-swapping-tesla-aims-to-charge-electric-cars-in-five-minutes/ There is a new gas station going in nearby, the station has Tesla superchargers there, the tan water tank seems to be the bottom of a giant purple/white/chocolate chip ice cream cone too. Achieving five-minute charges will require not only further improving the charging system, but also improving the interface with the electrical grid. As it is, only some places on the grid can handle 120-kilowatt charging. Drawing large amounts of power from the grid also incurs demand charges from the utility, increasing the cost of the system. The T1 Trust, PRR T1 Class 4-4-4-4 #5550, 1 of America's First HST's |
zoom3+1=4 Send message Joined: 30 Nov 03 Posts: 65839 Credit: 55,293,173 RAC: 49 |
Now here's an article on charging a bus, in 3 minutes... https://www.wired.com/2014/10/giant-charger-juices-electric-buses-three-minutes/ The Busbaar, introduced last month at the IAA conference, an annual trade show for commercial vehicles, looks something like the pantograph that pops up from high-speed electric trains to connect to overhead power lines. The Busbaar, though, comes down from a fixed position, hooking into a bus that parks beneath it, via a large copper bar installed on top of the vehicle. The T1 Trust, PRR T1 Class 4-4-4-4 #5550, 1 of America's First HST's |
Sirius B Send message Joined: 26 Dec 00 Posts: 24882 Credit: 3,081,182 RAC: 7 |
Introduced in Gothenburg nearly a year earlier. |
janneseti Send message Joined: 14 Oct 09 Posts: 14106 Credit: 655,366 RAC: 0 |
Introduced in Gothenburg nearly a year earlier. Yes. The system Volvo Opportunity Charging has been tested for two years and they will start operating in next summer. And in Göttingen Germany as well. Looks to me that the system is still under evaluation though and that it is only suitable to inner city traffic. But you always have to start somewhere. https://www.electricitygoteborg.se/en Electric and electric hybrid buses are automatically charged at end bus stops. Charging is fast and normally there is no need for schedule changes. • Volvo Opportunity Charging |
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