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Shenzhen Electrifies Entire Public Transit Bus Fleet

electrek.co

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Re: Shenzhen Electrifies Entire Public Transit Bus Fleet

#31

Post by userbinator »

Since transit buses are on fixed routes, I wonder why they didn't go with trolleybuses instead - no expensive batteries to replace (trolleybuses do have vestigial batteries, but they're much smaller and used for backup), thus better power-to-weight ratio, no need to wait for charging, and otherwise just as if not more environmentally friendly. When I was in Beijing, there were plenty of those.

(I know the ultimate source of power may be coal or oil, but it seems to me that even then, going directly from a power plant to the motor would be more efficient than an intermediate charging/discharging step.)

Re: Shenzhen Electrifies Entire Public Transit Bus Fleet

#32

Post by gumby »

userbinator wrote: post #31

Since transit buses are on fixed routes, I wonder why they didn't go with trolleybuses instead - no expensive batteries to replace (trolleybuses do have vestigial batteries, but they're much smaller and used for backup), thus better power-to-weight ratio, no need to wait for charging, and otherwise just as if not more environmentally friendly. When I was in Beijing, there were plenty of those. (I know the ultimate so…

By trolley bus do you mean what are also called “trackless trolleys” — busses with tires but no fuel storage that get power from an overhead line?

I’ve presumed that the infrastructure buildout and lack of flexibility make the TCO generally not worth it. In addition, if you need a mix you may get an economy of scale on one set of gear (maintenance, parts, flexibility etc — like a single-model-of-aircraft airline).

But this is speculation on my part

Re: Shenzhen Electrifies Entire Public Transit Bus Fleet

#33

Post by gumby »

Why is the US not investing in these kinds of infrastructure build outs? I’m not trying to start a flame war, I’m generally curious.

I understand the path dependence that, for example, made the US adopt mobile phones much later than everybody else (a modern and high quality wire plant that wasn’t yet amortized). Things like that make things like train networks hard to build too.

But bus fleets turn over relatively quickly and incrementally as well. What’s the barrier? The announced deployments all seem like small beer.

Re: Shenzhen Electrifies Entire Public Transit Bus Fleet

#34

Post by angled »

gumby wrote: post #32
userbinator wrote: post #31

Since transit buses are on fixed routes, I wonder why they didn't go with trolleybuses instead - no expensive batteries to replace (trolleybuses do have vestigial batteries, but they're much smaller and used for backup), thus better power-to-weight ratio, no need to wait for charging, and otherwise just as if not more environmentally friendly. When I was in Beijing, there were plenty of those. (I know the ultimate so…

By trolley bus do you mean what are also called “trackless trolleys” — busses with tires but no fuel storage that get power from an overhead line? I’ve presumed that the infrastructure buildout and lack of flexibility make the TCO generally not worth it. In addition, if you need a mix you may get an economy of scale on one set of gear (maintenance, parts, flexibility etc — like a single-model-of-aircraft airline). Bu…

Two other reasons may be aesthetics, and the environment - Beijing gets sandstorms but it doesn't get typhoons. Per CLP (just across the border in Hong Kong):

> More than 30% of CLP’s transmission network consists of overhead lines. There are more than 700 400kV transmission towers that form the backbone of its supply system. Overhead lines are exposed and susceptible to the influence of weather and the external environment. If a pylon is destroyed by strong winds or collapses because of a landslip, it will take several months to be back in order.

https://www.clp.com.hk/en/about-clp-site/corporate-informati...

Re: Shenzhen Electrifies Entire Public Transit Bus Fleet

#35

Post by goldenkey »

woodandsteel wrote: post #29
Gibbon1 wrote: post #26

Earlier quoted context omitted.

Two things to note about heavy vehicles. Often the power plant size is less than you would expect. Partly because drag is proportional to frontal area and goes up with the square of the vehicle size. While load is proportional to volume, goes up with the cube. That points to passenger cars being the worst case scenario, not trucks and buses. Second, batteries are a tech that just scales lineally. Double the capacity…

Buses don't need huge batteries for their size. A typical city bus goes only about 100 miles a day, they do a ton of regenerative breaking, and they can charge at stops and also they tend to sit in the terminal several times a day while the driver takes a break after each circuit. Electric trash collection trucks are even better. That's because they do so much regenerative breaking.

Regenerative braking doesn't do much for someone who already throttles properly. Garbage trucks dont have to drive in traffic. They dont get free energy for regen breaking..its just a recoup for bad driving conditions.

Re: Shenzhen Electrifies Entire Public Transit Bus Fleet

#36

Post by [deleted] »

gumby wrote: post #33

Why is the US not investing in these kinds of infrastructure build outs? I’m not trying to start a flame war, I’m generally curious. I understand the path dependence that, for example, made the US adopt mobile phones much later than everybody else (a modern and high quality wire plant that wasn’t yet amortized). Things like that make things like train networks hard to build too. But bus fleets turn over relatively qu…

[deleted]

Re: Shenzhen Electrifies Entire Public Transit Bus Fleet

#37

Post by jhobag »

jsemrau wrote: post #25
contingencies wrote: post #5

Living in Shenzhen, it feels like probably 80% of the taxis are electric already. Due to government subsidy the blue electric BYD cabs are more spacious, cheaper (no 2元 fuel surcharge), newer and cleaner than the older red cabs, which are generally clunky dirty squashed VWs. However, the drivers pay more to buy them even with subsidy, and you need a conventional ICE vehicle to get out to the factories in Dongguan, or…

Shenzen / Hong Kong will be the next Silicon Valley.

it already is

Re: Shenzhen Electrifies Entire Public Transit Bus Fleet

#38

Post by nerdponx »

gumby wrote: post #33

Why is the US not investing in these kinds of infrastructure build outs? I’m not trying to start a flame war, I’m generally curious. I understand the path dependence that, for example, made the US adopt mobile phones much later than everybody else (a modern and high quality wire plant that wasn’t yet amortized). Things like that make things like train networks hard to build too. But bus fleets turn over relatively qu…

Graft, inertia, and incompetence.

Re: Shenzhen Electrifies Entire Public Transit Bus Fleet

#39

Post by strommen »

gumby wrote: post #33

Why is the US not investing in these kinds of infrastructure build outs? I’m not trying to start a flame war, I’m generally curious. I understand the path dependence that, for example, made the US adopt mobile phones much later than everybody else (a modern and high quality wire plant that wasn’t yet amortized). Things like that make things like train networks hard to build too. But bus fleets turn over relatively qu…

China is moving unbelievably fast on electric vehicles. Their government is extremely motivated to stamp out air pollution, and there's nothing really stopping them. It's easy to spend lots of money on infrastructure when there is a rocket-ship economy and no political opposition.

The US is behind the rest of the world on vehicle electrification for a couple good reasons (very cheap gasoline and long distances between cities) and a few crappy ones (anti-science Republicans and large rent-seeking auto companies).

Re: Shenzhen Electrifies Entire Public Transit Bus Fleet

#40

Post by dayaz36 »

jsemrau wrote: post #25
contingencies wrote: post #5

Living in Shenzhen, it feels like probably 80% of the taxis are electric already. Due to government subsidy the blue electric BYD cabs are more spacious, cheaper (no 2元 fuel surcharge), newer and cleaner than the older red cabs, which are generally clunky dirty squashed VWs. However, the drivers pay more to buy them even with subsidy, and you need a conventional ICE vehicle to get out to the factories in Dongguan, or…

Shenzen / Hong Kong will be the next Silicon Valley.

It already is, but with a lot less bureaucracy. People get things done much quicker there
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