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Post by huon on Jan 31, 2013 12:36:49 GMT 9.5
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Post by huon on Feb 27, 2013 13:31:00 GMT 9.5
Volkswagen has just announced that they will go into limited production of their very efficient XL1: www.topgear.com/uk/car-news/volkswagen-xl1-2013-02-22This stunning plug-in hybrid should get over 140 miles per gallon of diesel, and around 10 miles per kWh of electricity. The car will be pricey--possibly $100,000+. But the technology will soon make it's way into other, more affordable cars.
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Post by huon on Feb 27, 2013 16:41:53 GMT 9.5
One correction: the Volkswagen XL1 will go about 6 miles (10 kilometers) per kWh, not 10 miles. Still amazing. All-electric range is up to 50 km.
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Post by huon on May 9, 2013 15:20:46 GMT 9.5
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Post by huon on May 10, 2013 8:06:00 GMT 9.5
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Post by edireland on May 10, 2013 9:40:45 GMT 9.5
Given its pricetag, I would expect it to score highly.
$90,000 for the one with the large battery?
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Post by huon on May 14, 2013 7:57:45 GMT 9.5
Actually, in its market segment of large luxury cars, the Tesla S is moderately priced--especially in the US where buyers get a $7,500 tax credit for the battery. After the credit, the base price for a Tesla is $72,400. And it's selling well: money.cnn.com/2013/05/13/autos/tesla-sales-bmw-mercedes-audi/For me, the chief benefit of the Tesla is its role as a flagship for a growing fleet of plug-in cars. And these cars represent the increasing efficiency and decarbonisation of transportation. Now, progress in promoting nuclear power and in adopting a US carbon tax can seem glacially slow. So for me the daily good news about plug-ins gives me hope that progress can be made, and indeed is being made, in these other areas.
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Post by edireland on May 14, 2013 8:35:12 GMT 9.5
Until we get an electric car with a large range that is under $20k, we haven't really got a chance of making a wide scale decarbonisation of transport happen.
Unless we all end up like Japan with 30% of passenger kilometres being on trains.
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Post by anonposter on May 14, 2013 10:29:11 GMT 9.5
Interesting that the other car that scored so high was the Lexus LS, an extremely quite luxury car.
Reading one of the comments it also appears that the ability to use the carpool lane with only one person is well liked by owners.
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Post by trag on May 15, 2013 2:14:14 GMT 9.5
Until we get an electric car with a large range that is under $20k, we haven't really got a chance of making a wide scale decarbonisation of transport happen. Unless we all end up like Japan with 30% of passenger kilometres being on trains. How far could we (for vague values of "we", USA, Australia, UK?) get if we electrified the rail system, expanded the rail network and added taxes on the intercity transport of goods by truck, to at least a high enough value to maintain the interstate highways that the trucks are ruining. In other words, do what we can to get as much freight as practical on electric trains. Can electric rail systems (overhead cable, third rail?) provide enough power for freight engines? I have long thought that if we as a society (or for that matter, Al Gore) were serious about addressing CO2 emissions, then back in 2000 someone would have stood up and said, "We need to reduce CO2 emissions. Our electical systems and our transportation infrastructure are almost completely separate, so they can be addressed separately. We'll eliminate CO2 from our electrical generation system by switching to nuclear because simple arithmetic shows that wind and solar will never do the job and would cause electricity prices to quadruple or worse if we try. We don't have a currently useable solution for our transportation infrastructure, but we'll start by moving more freight to trains and embark on a system to electrify our rail systems."
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Post by edireland on May 15, 2013 5:20:47 GMT 9.5
Railfreight most certainly can be electrified, here is a 6000hp electric locomotive, and if that is not enough horsepower there is always the Iore which has 14700hp for a coupled pair. (That runs on Iron ore trains in Sweden). However railway electrification has now reached something on order of $2.3m/track.km in the UK, although that is Overhead line equipment meant for 100mph running. Slower freight only equipment would probably be half the price or something of that order, but still the amount of track that would have to be electrified to make a significant difference is just staggering. I estimated decarbonisation of the electricity/domestic heating supply would get carbon emissions in the UK down close to 70% with the largest holdouts being transport. Transport however is dominated by private car emissions, with the railways in teh UK only consuming ~570,000t of oil a year.
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Post by anonposter on May 15, 2013 9:48:41 GMT 9.5
Moving long distance freight to rail would help even with diesel locomotives due to the lower rolling resistance of steel on steel.
If your electricity grid is high carbon then electric rail can actually increase CO2 emissions over using diesel trains so if you're doing it for environmental reasons you need to have electricity generation somewhat sorted first.
Better urban and suburban public transport could help with reducing private car emissions.
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Post by edireland on May 15, 2013 11:17:24 GMT 9.5
There are numerous other operational advantages to electric rail traction even in the no-carbon saving case of high carbon electricity. (And that situation is very hard to end up at, since electric locomotives can run regenerative braking into the grid, cutting energy production 20%, and before static power generators tend to be far more efficient than the medium/low speed diesels in locomotives).
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Post by anonposter on May 15, 2013 16:32:27 GMT 9.5
There are numerous other operational advantages to electric rail traction even in the no-carbon saving case of high carbon electricity. True, they tend to be most important on short runs or difficult terrain. (And that situation is very hard to end up at, since electric locomotives can run regenerative braking into the grid, cutting energy production 20%, Not so relevant to long distance trains that don't have to slow down much. and before static power generators tend to be far more efficient than the medium/low speed diesels in locomotives). OTOH you also have line losses from the power plant to the train (and there are diesel-hydraulic trains, mostly DMUs though, but they do get better efficiency than diesel-electric).
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Post by jagdish on May 15, 2013 17:09:24 GMT 9.5
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Post by anonposter on May 15, 2013 17:50:42 GMT 9.5
Methanol is promising for fuel cell applications, especially with a reformer on board.
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Post by grlcowan on May 16, 2013 3:59:50 GMT 9.5
Fuel cells are improving in efficiency... Do you have unevasive references for fuel cells' fuel consumption per watt-hour of DC output in or around 2008, and similarly candid references for the same this year or last? Please post them.
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Post by huon on May 28, 2013 16:03:46 GMT 9.5
Methanol is, indeed, a promising fuel. In fact, George Olah and others have proposed a whole "methanol economy". Here is the first paragraph from the Wikipedia entry: The methanol economy is a suggested future economy in which methanol replaces fossil fuels as a means of energy storage, ground transportation fuel, and raw material for synthetic hydrocarbons and their products. It offers an alternative to the proposed hydrogen economy or ethanol economy.en.wikipedia.org/wiki/Methanol_economy
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Post by anonposter on May 28, 2013 16:46:51 GMT 9.5
The ethanol economy and hydrogen economy do have some pretty serious problems (though I suppose ethanol could work if it were synfuels instead of biofuels).
Energy density is still a bit low but the superior efficiency of fuels cells should be enough to offset it and give comparable range, won't do for planes though.
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Post by edireland on May 28, 2013 20:57:05 GMT 9.5
Methanol means Methanol-to-Gasoline and similar processes.
WHich means energy density is the same as now.
Assuming we can make methanol cheap enough, it is also animal feed thanks to "Pruteen". But making it cheap enough is the big problem.
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Post by anonposter on May 29, 2013 6:12:11 GMT 9.5
Methanol means Methanol-to-Gasoline and similar processes. WHich means energy density is the same as now. But would petrol work as well in a fuel cell? Sure, if we still use internal combustion engines that'd be the way to go but fuel cells are likely better off running on straight methanol.
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Post by huon on May 30, 2013 16:03:39 GMT 9.5
From a recent review of the Tesla S:
I'm riding in a red Tesla S, the stunning all-electric vehicle from PayPal founder Elon Musk, and realize that this is less a car than a piece of philosophy. In a world beset by environmental pessimism, where many believe we must lower our expectations, downsize our lives, and adjust to the notion that tomorrow will be worse off than today, Tesla offer a rip-roaring, 120 mph riposte. It turns out we can have it all.
("An electrifying ride" by Tom Keane; Boston Globe, May 21, 2013)
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Post by edireland on May 30, 2013 23:40:37 GMT 9.5
Now find everyone $80,000 to buy one wiht a decent sized battery.
There are far more efficient ways to cut emissions.
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Post by huon on May 31, 2013 15:45:08 GMT 9.5
More from the Tesla S review: ...Ignore the environmental benefits and it's still the best car in the world.
On the other hand, it costs anywhere from $62,400 to $87, 400--and that's after a federal tax credit of $7,500. So I'm not buying it. My guess is, neither are you.
So why the enthusiasm for something priced so far out of the reach of almost every American? Maybe for the same reason that the first computers were so exciting.... [Their] price was also ridiculously high. But the potential of that technology launched a revolution, one that eventually made computers affordable to almost everyone....
Last quarter Tesla only sold 4,750 cars--a trivial amount compared to the entire automotive industry. Yet as I sit in the Tesla S, the ride whisper quiet, the car effortlessly gliding around sharp turns, I'n reminded of that first PC. Tesla may well be about to spark a revolution of its own. www.bostonglobe.com/opinion/2013/05/20/the-thrill-ride-tesla/1oHpX66Z426jCZKNbavaqM/story.html
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Post by edireland on Jun 7, 2013 9:17:20 GMT 9.5
I did some number crunching on trolleybusses a while back.
And I came crunched an estimate that a route average of ~100 round trips per day with double decker vehicles would be superior in economic terms to normal motorbuses, even assuming no fuel taxes to speak of.
This changes slightly with hybrid buses but not drastically.
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Post by anonposter on Jun 7, 2013 23:20:06 GMT 9.5
I did some number crunching on trolleybusses a while back. And I came crunched an estimate that a route average of ~100 round trips per day with double decker vehicles would be superior in economic terms to normal motorbuses, even assuming no fuel taxes to speak of. This changes slightly with hybrid buses but not drastically. That'd be a bus about every 15 minutes if running the same service standard all day long, given the existence of something called nightime I'd say you'd have to run a bus every 10 minutes during the day (probably every 5 in peak) and then drop down to every half hour overnight. In Australia it's mostly city centres which have that level of service and most of that is as a combination of other services to different destinations. Though if you go to the expense of dedicated right of way (which is what you'd need if you really want people to leave their cars at home) you'll pretty quickly find that light rail won't be all that much more expensive while having lower running costs. Main purpose of trolleybuses from my point of view is for hilly terrain where rail has trouble.
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Post by edireland on Jun 7, 2013 23:58:15 GMT 9.5
I live within a hundred yards of a bus corridor with more than 30 busses per hour in each direction. So that tends to skew your perspective. (And most of the routes on the corridor terminate within a mile of it, so the average per route mile is still huge).
Thing is, with Trolleybus/bus rapid transit a "dedicated right of way" is some paint on the tarmac. With a tramway you have to dig up the street and move all the utilities to make way for the track slab. The costs of that can very easily baloon to absurd levels.
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Post by anonposter on Jun 8, 2013 1:58:32 GMT 9.5
Thing is, with Trolleybus/bus rapid transit a "dedicated right of way" is some paint on the tarmac. Of course you've got to enforce a bus lane for it to be of any use (if regular cars often drive in it or worse, park in it, it won't help the bus beat a regular car). At the very least that argues for having a physical barrier to keep cars out. With a tramway you have to dig up the street and move all the utilities to make way for the track slab. The costs of that can very easily baloon to absurd levels. Of course if you're installing overhead wires you may to have to move things around to make way for them even if all else you'll do is repaint the road and it will add cost (more for the overhead than with light rail since you need two wires for trolleybuses).
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Post by edireland on Jun 8, 2013 2:08:22 GMT 9.5
Overhead costs for trams tends to be a very small proportion of the total cost of the system. Especially as innovations with parafil ropes make it practical to simply attach the cabling to adjacent buildings or to use combined streetlight-support posts. Additionally you have to worry about galvanic corrosion of things close to the rails in a light rail system since the rail is grounded and has significant currents flowing through it. With trolleybuses the circuit is entirely closed.
The real reason Light rail costs such an absurd amount of money is rerouting all the utilities, and in my experience with bus lanes, people driving in them without the right to do so is a minor problem, and does not significantly reduce average speeds. Trolleybuses will beat conventional buses and light rail in terms of travel speed when stops are close together as they are on many bus routes simply because they will have superior acceleration to either of them. (Due to having an electric transmision and lots of power in the first case, and because rubber tyre interfaces are inherently faster accelerating than steel wheel-on-rail systems in the latter case).
The relatively low cost of installations - based on experience in Vancouver I estimate ~£813k/double lane kilometre (roughly $1.26m US) has to be a big selling point.
That isn't really that much compared to light rail projects which can rapidly baloon out of control.
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Post by jagdish on Jun 9, 2013 19:15:31 GMT 9.5
Batteries are the costly part of electric vehicles. Higher capacity batteries may be a long time in coming. The near term solutions are:- 1. Fuel cells working on methyl alcohol. 2. Use electric vehicles for feasible distances with trains/ferries for longer distances. 3. Solar roofs could also be used as they are getting cheaper. This will help to use electrification to reduce hydrocarbon use. The electric power could further be hydro or nuclear as economics permit. We have to use a combination technologies and not condemn any one out of hand.
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