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The Physics and Economics of Moving 44 Tonnes at 56mph

mikeayles.com

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Re: The Physics and Economics of Moving 44 Tonnes at 56mph

#71

Post by ahartmetz »

newsclues wrote: post #18
dzonga wrote: post #7

Earlier quoted context omitted.

this is well written. thank you - you broke down the economics nicely. I do think maybe with a hub & spoke model - big trucks move loads to hubs -- then smaller electrified trucks cover the less than 200 miles from hub to spoke. electrified smaller trucks and vans are already economical today. you get to benefit from using diesel for long haul routes - while also - better economics on the electrified front i.e a hybr…

Trains for longer distances and then electric trucks for last mile

Maybe there are ways to make that faster and cheaper now with more computers and automation.

Re: The Physics and Economics of Moving 44 Tonnes at 56mph

#72

Post by mikestew »

aitchnyu wrote: post #56

Tangential, do vehicles detect motion by crosswind or road camber and compensate? I saw some social media post of lots of trucks toppled over by crosswind.

Our camper van (which is a tall sail) compensates for sidewinds. Other RVs can have this feature as well, though often as aftermarket fitment. Pretty neat when it works, “man, sure is windy today, but this van is a lot easier drive in the crosswind than our old RV. Oh…”

But an RV is not a semi tractor-trailer setup. In fact, crosswind compensation is something I’ve only seen on RVs that don’t involve a trailer (Class A, Class C). And for a semi, how much is in the trailer? Seems a compensation system would need to know that.

Re: The Physics and Economics of Moving 44 Tonnes at 56mph

#73

Post by mikestew »

close04 wrote: post #42
hnthrow0287345 wrote: post #21

>Most assume the truck driver is being inconsiderate. You could probably add a whole section of specifically learning to drive a car with trucks on the road to driver education programs and it would do wonders for traffic. >Anti-idle ordinances exist in several US states and EU regulation is moving in this direction. Yep, grab a sleeping bag or take your clothes off and use evaporation cooling on yourself. The good n…

> Yep, grab a sleeping bag or take your clothes off and use evaporation cooling on yourself. Talking about driver education, refrigerated trucks never get to turn off the engine until they unload the cargo. So it's not always for comfort. > if you can readily stop somewhere for a safe place to sleep That's the missing infrastructure. Drivers pull over to sleep when they hit their daily driving limit and in Europe mos…

Talking about driver education, refrigerated trucks never get to turn off the engine until they unload the cargo.

The refrigeration unit often runs on a separate unit powered by its own engine, not the engine powering the truck. Don’t get excited just yet, as those engines do not run clean. They do use less fuel than the truck’s engine, though.

Re: The Physics and Economics of Moving 44 Tonnes at 56mph

#74

Post by mschuster91 »

izacus wrote: post #44
NomadicDaggy wrote: post #11

> This isn’t advisory. It’s a physical limiter in the engine’s ECU. The truck cannot go faster. I live in Latvia (in the EU) and see a significant part of our ARTICs on the roads go well past 90km/h daily. I presume their fleets do monitor the speed and alert the driver if speeding for a prolonged period of time but they are obviously not physically limited. Maybe the limits do come from the factory but get disabled?…

Tachographs are mandatory and monitored across the EU so I very much doubt that's really happening.

Just because something is mandatory, doesn't mean it's enforced. You got 6 million trucks registered in the EU alone [1], plus fleets of trucks registered in adjacent states such as Turkey or Serbia, or old trucks out of the new Eastern European states that predate their EU membership and, with it, mandatory governors. And loggers can be manipulated as well, if you do it right there is no chance of finding that out without taking apart the truck.

Not every country is as thorough as Germany is in technical inspections, trucks from outside the EU don't need speed governors, and as long as you don't race your truck in Germany, France or Austria, chances are high no one will be bothered enough to pull your truck over for a detailed inspection on an examination wheel. Or you simply have two datalogger cards, that you swap out when going into one of these countries.

[1] https://trans.info/de/eu-lkws-alternde-flotten-449472

Re: The Physics and Economics of Moving 44 Tonnes at 56mph

#76

Post by ben_w »

schiffern wrote: post #51
ZeroGravitas wrote: post #45

The (bad) justification for overtaking seems a much better justification for the slower truck to fix their calibration and go faster. Lots of good info but it all feels a bit like it is being used to create a "just so story" to support whatever the current status quo is.

Right. If 0.5 mph is so valuable (which I believe), how do we explain the slow trucks? How do we fix the slow trucks?

IIRC, the difference in radius between fresh tires and those worn down to just before they need replacing, changes the actual speed at any given speedometer reading by about 2%.

C=πD and all that.

Re: The Physics and Economics of Moving 44 Tonnes at 56mph

#77

Post by jillesvangurp »

mikeayles wrote: post #65
jillesvangurp wrote: post #52

> A diesel fuel tank for 400 litres of diesel weighs roughly 350 kg (the tank itself is relatively light; diesel is 0.84 kg/L). A battery pack storing equivalent energy would weigh on the order of 16 tonnes at current lithium-ion energy densities. That’s not just additional weight. It’s 16 tonnes of payload that disappears. And yet, electrical semis exist that come without 16 ton batteries. The fallacy here is that m…

Fantastic comment, thanks! A review of the state of BEV's was actually going to be one of my next articles (hopefully after the additives). Are you happy for me to drop you an email to review a draft when I'm ready?

sure, please do

Re: The Physics and Economics of Moving 44 Tonnes at 56mph

#78

Post by toss1 »

dmurray wrote: post #8

> At 0.5 mph differential, the overtake takes 291 seconds — over a minute of blocking the outside lane. Annoying, but it gains the driver 5.0 extra miles across a working day. The driver gets there 5 minutes earlier in exchange for causing a 7-km tailback multiple times per day? That seems like exactly the kind of thing that should be regulated away: the truck in front is limited to 90 km/h, you're limited to 90 km/h…

>>That seems like exactly the kind of thing that should be regulated away

Yes, and the regulation should NOT be limiting passing or requiring the slower truck to brake

It should allow a "Push To Pass" button that allows a 10mph boost for enough seconds to make a pass in a reasonable amount of distance so as to not create problems for other traffic.

Current technology would allow these to be easily limited to X uses per hour/day and even geo-fence the usage for safe zones (use could even be limited to passing lanes so the truck being passed cannot start a drag race to stay ahead). They could even require connectivity and disable it in poor road conditions.

The real people being inconsiderate are not so much the truckers (particularly the slower trucker failing to yield and let the other one pass in a reasonable distance), as it is the regulators who created this mess.

Re: The Physics and Economics of Moving 44 Tonnes at 56mph

#79

Post by conscion »

citrin_ru wrote: post #49

> Rail is superb for what it does: moving bulk commodities... The problem is last-mile. Before around 1950x-1970x rail networks were more dense (at least in Europe) - any significant goods source/destination (like a warehouse, a factory e. t. c.) had a railway spur. Lots of rail tracks / spurs were abandoned /removed when it was widely believed that trucks are the future and railways are outdated. If all these spurs…

I think they gloss over a major factor also. They mention:

> Distribution centres are built around motorway junctions (J24 of the M1, the Golden Triangle in the East Midlands) because that’s where road access is.

But they skip _why_ is that road access and motor junction there. It's there because the government decided building roads was something that was it's responsibility. I know this article is UK focused, but for the US if the government decided to build rails also, then they could put them in more convenient places. Instead they allow rail companies to decide which monopoly corridors the companies get to control.

Re: The Physics and Economics of Moving 44 Tonnes at 56mph

#80

Post by jdeibele »

mikeayles wrote: post #47
kqr wrote: post #38

Earlier quoted context omitted.

Do you have an RSS feed for your blog?

I do now: https://www.mikeayles.com/rss.xml

NetNewsWire can't find that feed.

"Can’t add a feed because no feed was found."

I used the RSS validator at w3.org

https://validator.w3.org/feed/check.cgi?url=https%3A%2F%2Fww...

This feed is valid, but interoperability with the widest range of feed readers could be improved by implementing the following recommendations.

line 1, column 10821: Missing atom:link with rel="self" [help]

... category>Web ^

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