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To Really Cut Emissions, We Need Electric Buses, Not Just Electric Cars
An anonymous reader writes: All the EV attention these days is going to Tesla and other sedan manufacturers, but this article makes the case that it's far more important to switch our buses over to electric power than our cars. "Last year, according to the American Public Transportation Association, buses hauled 5.36 billion passengers. While usage has fallen in recent years, thanks in part to the growth of light rail and subway systems, buses still account for more rides each year than heavy rail, light rail, and commuter rail combined—and for about half of all public transit trips." This, while managing around 4-5 miles per gallon of gas, and public buses usually average about 50,000 miles per year. The electric buses themselves are significantly more expensive, but the difference is made up dramatically lower fuel costs. And there will be difficulties: "The range—up to 30 miles—limits Proterra buses to certain routes, so it's hard for an agency to go all in. Drivers have to be trained to brake and accelerate differently, and to maneuver into the docking stations. And Doran Barnes of Foothill Transit notes that some of the cost advantage of using electricity instead of diesel can dissipate. Electric cars can be charged at night, when power prices are low. But buses have no choice but to recharge in the middle of the day, when utilities often impose higher peak usage rates."
Diesel engines are powerful but they pollute A LOT. And don't forget ships. That bunker fuel many of them burn is NASTY.
Pain is merely failure leaving the body
I know i'm old but there was a time when most buses ran off electricity using an overhead wire for power transfer. What's with wanting to go to battery power for this use. It's not like we could have forgotten this technology and with an update using today's technology we have to be able to make it better. Buses have defined routes so we can't argue that it limits flexibility...buses aren't cars, they don't have to be able to go down every road.
The biggest inefficiency with a (short-route) bus is stop-starting a heavy vehicle laden with people.
We have electric and hybrid buses in London, but using a Flywheel (first developed as a fuel-saving measure for F1 cars) to preserve kinetic energy has made the greatest difference to efficiency for London buses.
Shanghai has had some buses using these for several years. They recharge at some of the bus stops.
I read the entire article, and the full summary, and no where is mentioned to single most important datapoint for evaluating the claim in the headline:
How much total CO2 is generated by buses as compared to cars? Since they didn't put it in the article (and since the article reads like an advertisement for an electric bus company), I'm going to guess it's just an advertisement.
"First they came for the slanderers and i said nothing."
A bus will only get a few mpg, but carries a lot more people.
Sometimes it does. I see a lot of buses driving around 90+% empty.
I don't care if it's 90,000 hectares. That lake was not my doing.
If you are going to be limited to certain routes, why not electrify the routes and then save the weight of the batteries? Then you won't have to worry about recharge times either so you'll get more daily miles out of each bus too.
You might get the occasional free-rider but only on april 1st.
Instead of a single bus driving around picking people up and dropping them off, have stands with small electric vehicles for individuals. Instead of waiting for a bus, you go to a stand and check out a vehicle and drive it to where you want. Or it drives itself. With self-driving electric vehicles, you could keep all the stands in supply.
I see a lot of cars driving around 80% empty. To and from work, I must admit that one of them is mine.
Humans like cars, not buses.
And if you taxed larger or powerful cars heavily*, people would drive more fuel efficient cars. High gas taxes are doing that in some parts of Europe.
In the USA, at least, cars are a status/phallic symbol and thus are larger and/or more powerful than they need to be in a practical sense. There are times I wanted a more powerful car to compete with other more powerful cars during rush hour. But that's size escalation. If you lower the average then there is less need to compete with beefy cars.
Further, taxing beefy cars would encourage more to take public transportation. I know conservatives will balk, but taxes would help with three problems: traffic, pollution (and GW), and gas dependance. Four actually: gov't revenue to help pay down debt and other uses.
* Exemptions would be made for large families and legitimate business use.
Table-ized A.I.
In San Francisco a good percentage of our bus fleet is electric with overhead wires, so the tech is still there, works great, and is not as expensive and problematic as batteries. Trolley buses, look it up. Only issue is the wires are U G L Y
The newer buses even have enough battery power to go a block or two off the wires on battery power and pass an obstruction, something that would bring the old trolley bus system to a standstill.
The largest container ships have huge particulate emissions, but that's because there's no regulation on particulate emissions according to international law. It would be difficult to change that, because regulating ships requires an international agreement. That said, it should be done.
However, ships already have extremely low CO2 emissions per ton-mile. They are already extremely fuel-efficient. The largest ships have 1/15th the fuel usage and CO2 emissions per ton-mile as a tractor-trailer truck, and massively better than your car. If you drive one mile to the store to buy an article of clothing, you have emitted vastly more CO2 than was emitted by shipping it halfway around the globe by containership.
That will have almost no effect on your CO2 emissions.
San Francisco still has a ton of trolley buses. We also have old and new trolley cars on rails.
I much prefer electric trolley buses to diesel and natural gas buses. Trolley buses have insane acceleration, presumably better even than battery-electric buses. Without traffic they can really haul-butt, which admittedly sucks if you suffer from motion sickness (as I do), but at least you can get off sooner.
And, personally, I prefer the wires. They give the bus line a feeling of permanence similar to rails. From transit agencies' perspective the ability to easily re-route is a big win. But from commuters' and property owners' perspectives, that's a huge negative.
We should have been working hard at improving nuclear power, and solving its problems, to the point that this would, by now, be a no-brainer. So those polluting diesels are another thing we can blame on the environmentalists that shut down nuclear power research in the '70s.
Prediction for end of Universe #42: Fencepost error in Quantum_bogosort.cpp
San Francisco has had a fairly extensive trolleybus network since the 1930s. Although only 15 bus lines are trolleybuses, those are the most crowded bus lines, so a significant fraction of bus traffic there is electrified.
It appears that diesel buses cost $450,000, and battery-electric buses cost $825,000, and trolleybuses cost $1m each. Trolleybuses last at least twice as long as diesel buses. The overhead wires cost $2 million per mile and last almost indefinitely, it appears, because I have never seen maintenance being performed on any of them, in contrast to roads and stoplights which are being repaired constantly, and buses which are being replaced often enough.
San Francisco has 300 trolleybuses for 15 lines, and each line is about 6 miles long. Thus the overhead wires cost $180m, the buses cost $300m, and the electricity costs $48m over 24 years. It appears that equivalent diesel buses would cost $270m and use $330m in fuel over 24 years, servicing the same routes (just using the numbers I read from an article and doing the calculation manually). It would appear that trolleybuses cost ~$528m for those routes and diesel buses would cost ~$600m. However, that's not taking into account financing costs etc, which would probably make the trolleybuses more expensive than diesel ones since the upfront cost is higher. Also, this is for routes in San Francisco which are only 6 miles long; the economics may change for suburban routes.
That said, it doesn't seem like the costs are very different whether we choose trolleybuses, diesel buses, or battery-electric buses. It may be slightly more expensive to go electric, but not much.
They're called trollybusses and lots of cities used to have them. Apparently hundreds of cities in the US had them but most of them went away in the 1950's and 1960's. Currently they're only in use in Boston, Dayton, Philadelphia, Seattle, and San Francisco (List of US Trollybusses). I was recently in San Francisco on a tour bus and they said the reason they use them is the electric motor has more torque which is needed to go up the steep hills. I can't speak for why they're still in use in the other cities or why they went out of style in all but 5 cities. Growing up in Dayton I thought they were more common than they are since Dayton isn't that big of a city compared to the others on the list.
I see a lot of cars driving around 80% empty. To and from work, I must admit that one of them is mine.
You wastrel... At least my Ferrari is only 50% empty!
Vancouver, BC has a very extensive trolleybus network, with 265 active trolley busses. The system works quite well, and the busses do have battery backup, so they can go off the wires for short periods of time (to go around road construction, accident, pass a parked bus, etc...). As for the wires being ugly? I dunno, they're just part of the fabric of the city. There are some intersections though with rather impressive spider webs hanging over them. :)
...si hoc legere nimium eruditionis habes...
The largest container ships have huge particulate emissions, but that's because there's no regulation on particulate emissions according to international law.
The lack of regulations is why container ships use Bunker No. 6.
It is one grade above the stuff we use to make asphalt and the dirtiest part of oil that can still be used for fuel.
If allowed to cool to room temperature, it turns into a semi-solid.
Countries have started creating regulations for marine engine particulate emissions near their shores,
but banning bunker fuel would have serious effects on the global shipping industry and product prices.
[Fuck Beta]
o0t!
It's my understanding that the electricity for the trolley buses is free. San Francisco owns the Hetch Hetchy Dam and all city services are run off that power. In fact, under the terms of the Raker Act San Francisco isn't supposed to use it for anything but public services in the city, although they've never strictly complied with that requirement.
However, heavy bunkers are hell on the top cylinder in slow speed diesels (110 rpm or less). Valve metallurgy has
negated a lot of the effects of this and although steam plants can use heavy oil they lose a lot of energy transfer
and hence are not very efficient. Medimum speed (Above 200 rpm) have terrible reliability problems trying to burn
bunkers. A lot of companies insist that the cheap fuel saves money but it's double edged versus the overtime they
pay engineers for valve maintenance. Exhaust temperatures tend to be a lot higher burning bunkers (150c or so
higher) and the risk of stack fires with high sulfur/carbon content increases dramatically if any turbo oxygen reaches
the stack. Total hydrocarbon consumption by ships as a percentage of all consumption is probably not that high and
alternative vegetable fuels work quite well for the most part in either slow or medium speed engines. The veg oil
market doesn't have the volume to supply all forms of transportation but in a narrow segment such as shipping,
it might be viable as an alternative. The billionaire shipping companies have been screwing around with the fuel
cost/maintenance cost issues for years. They'll do anything to save a penny. Tax breaks and subsidies to use
alternative fuels makes sense in this case. (In my belief.)
Seriously? Do you really believe a bunch of hippies put the breaks on something as profitable as Nuclear power?
Coal and oil lobbies, the folks paid to store nuclear waste instead of processing it into new power. Look at those folks. Follow the money. When anything of importance happens it's always money.
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They use what is called a "Viscotherm" which is a 10kw electric heater to warm the fuel. Not exhaust.
Sorry. Been this way since the steam days. They use either an auxillary 500kw diesel (cat 396, Jimmy
1271) or an online steam Turbo generator in the case of a steam plant. This is a fatal negative feedback
loop in the steam case. If you lose the TG you lose fuel, hence the diesel backup for the viscotherm.
Yes, I'm a marine engineer.
A 30 mile range? What kind junk are the buying?
A BYD electric bus has a nominal range of 155 miles. It sounds much more reasonable to me.
a,e,i,o,u and sometimes w and y (at be if of up cwm by)
The range is 30 miles. Periodically, the busses will fully recharge in seven and half minutes.
StarMetro in Tallahassee, which has a fleet of 72 diesel buses, found itself coping with budget problems when the price of diesel spiked in 2007. Fuel is typically the second-highest cost for a transit system, behind labor. StarMetro was Proterra’s third customer, ordering three buses in 2010 and two more in 2011, backed by federal funds. “We put them on our most visible route,” said Ralph Wilder, superintendent of transit maintenance. The buses can easily handle the 18-mile loop, which runs from Tallahassee Community College to the Governor’s Square Mall. On this route, all buses stop for 10 minutes in the middle, to wait for connections, so charging up the electric ones doesn’t add any time to the trips. Recharging takes about 7.5 minutes.
So, $825,000 for the electric bus, but only $80,000 in fuel costs over 12 years, vs $447,000 for a diesel bus with $500,000 in fuel costs. In theory, economical, but there are also air quality improvements-- depending on how the electricity is sourced.
I grew up using Wellington's electric buses my entire life. ...
And now the council is going to scrap the lot of them - how fitting that slashdot should run an article
http://www.stuff.co.nz/national/10202967/Wellingtons-trolley-buses-to-go
Politicians in the pockets of industry again...
I think it's very safe to assume that nearly every single person reading this site or writing comments here has ridden on a bus.
Yes, I'd prefer driving a Ferrari along a deserted Autobahn at top speed to riding a bus. Stuck in traffic and looking for ages for an ultimately expensive parking spot - that bus is looking good. Trains look even better especially with WiFi.