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Mexico building rail rival as water shortages drain Panama Canal

japantimes.co.jp

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Re: Mexico building rail rival as water shortages drain Panama Canal

#91

Post by reactordev »

jefftk wrote: post #87
reactordev wrote: post #86

Earlier quoted context omitted.

North of 55 is ice sheets. South 55 is Cape Horn. Not saying it can’t be done. Just not something you just “do” except for Vikings.

North of 55 has ice, but isn't all ice sheets. The most extreme example is probably the warm water port of Murmansk at 68° 58'.

Only because of the North Atlantic Gulf Stream bringing warmer waters. Everywhere else around there is closed in the winter due to ice. Murmansk is a freak of nature, an exception to the rule, like how you can’t freeze vodka in a normal freezer.

Re: Mexico building rail rival as water shortages drain Panama Canal

#92

Post by timeagain »

RagnarD wrote: post #90

I'm wondering why the whole thing is an issue anyway. Why is there a water shortage? There's an entire ocean on both sides of the canal. Gatun Lake provides the water buffer for the canal. Currently it's freshwater based but it's also artificial to begin with. Why not transition to using salt water pumped from the oceans to top it off as needed? Seems a hell of a lot easier than trying to replace the canals with rail…

Gatún Lake is 425 km^2. It provides the drinking water for Panama City. It has a watershed covering a large portion of the country. You might be underestimating the scale of the problem.

Re: Mexico building rail rival as water shortages drain Panama Canal

#93

Post by jodrellblank »

RagnarD wrote: post #90

I'm wondering why the whole thing is an issue anyway. Why is there a water shortage? There's an entire ocean on both sides of the canal. Gatun Lake provides the water buffer for the canal. Currently it's freshwater based but it's also artificial to begin with. Why not transition to using salt water pumped from the oceans to top it off as needed? Seems a hell of a lot easier than trying to replace the canals with rail…

"Every ship traversing the canal between the Atlantic and Pacific oceans requires 50 million gallons of fresh water"[1]. And it can transit 40 ships per day[2]. So, lifting 2 billion gallons of water, just over 9 billion litres, up to the 26 metres altitude of Gatun Lake.

Wondering how plausible that is, the numbers match very closely to the Dinorwig pumped-storage hydroelectric power plant in the UK[3], which stores ~9.2GWh of energy by pumping 9.2 million cubic metres of water, 9.2 billion litres, up 536 metres to Marchlyn Mawr reservoir. And it takes 7 hours to do that[4].

If the same amount of water has to be lifted only ~5% of the height, assume 5% of the energy, that would be ~450MWh/day for the Panama Canal.

I see it wouldn't be good to dump ocean water into Gatun Lake, but could the lowest locks of freshwater be pumped back up, instead of released into the ocean?

[1] https://ctmirror.org/2023/08/27/the-panama-canal-is-running-...

[2] https://www.marineinsight.com/guidelines/10-important-panama...

[3] https://en.wikipedia.org/wiki/Dinorwig_Power_Station#

[4] https://www.thegreenage.co.uk/cos/dinorwig-hydroelectric-pla...

Re: Mexico building rail rival as water shortages drain Panama Canal

#94

Post by RagnarD »

timeagain wrote: post #92
RagnarD wrote: post #90

I'm wondering why the whole thing is an issue anyway. Why is there a water shortage? There's an entire ocean on both sides of the canal. Gatun Lake provides the water buffer for the canal. Currently it's freshwater based but it's also artificial to begin with. Why not transition to using salt water pumped from the oceans to top it off as needed? Seems a hell of a lot easier than trying to replace the canals with rail…

Gatún Lake is 425 km^2. It provides the drinking water for Panama City. It has a watershed covering a large portion of the country. You might be underestimating the scale of the problem.

A refinement of the thought, then, would be to install a small modular nuclear reactor to power desalination plants to replenish the freshwater when needed. Panama City must also be threatened if the lake level is that low.

Re: Mexico building rail rival as water shortages drain Panama Canal

#95

Post by jodrellblank »

foota wrote: post #33
bilsbie wrote: post #5

Surely this is a mega project: but naively, what if we built say ten parallel railways 10 ft apart and moved cargo ships over the rails? Or this guy only needs to be scaled up 10X to do the job. Not outside the realm of imagination? https://en.m.wikipedia.org/wiki/Crawler-transporter I know the ships are huge and it shouldn’t be feasible but it would be interesting to run the numbers. Edit. Actually if my math is rig…

There's precedence for this (on smaller scales), see https://en.m.wikipedia.org/wiki/Portage#:~:text=Portage%20or... .

And https://en.wikipedia.org/wiki/Fitzcarraldo

Re: Mexico building rail rival as water shortages drain Panama Canal

#96

Post by jodrellblank »

myself248 wrote: post #67
redleader55 wrote: post #41

Earlier quoted context omitted.

Just adding a few small details here: 1. When the canal was built, it was deemed to hard and expensive to dig at the level of the two oceans so they imagined the locks system as a solution for that. Back then, the canal was built with US money in a time of conflict between Panama(which was part of Colombia) and Colombia. Today Panama is an independent country, but they don't have the finances to upgrade the canal. 2.…

Agreed, pumping sea water seems terrible, but it also seems like there'd be no reason to do that. First, at either end of the system there's a chunk of river at sea-level-ish but flowing towards the sea, so the water up at the upstream end where the lower locks are is probably not salty at all. Second, if each lock had its own pumps, doing it in 3 short lifts rather than 1 big lift to the top, then even if the one or…

I did my own estimate ( https://news.ycombinator.com/item?id=38997124 ) via a different method, before reading down to yours, and got ~450MWh of energy needed - which is close enough to your 521MWh that I'm pretty happy.

> "Nah. Let's do it with solar."

Why not with hydroelectric? Store power by pumping water up to Gatun Lake, generate power while filling the locks as the water falls down...

Re: Mexico building rail rival as water shortages drain Panama Canal

#97

Post by jodrellblank »

bilsbie wrote: post #5

Surely this is a mega project: but naively, what if we built say ten parallel railways 10 ft apart and moved cargo ships over the rails? Or this guy only needs to be scaled up 10X to do the job. Not outside the realm of imagination? https://en.m.wikipedia.org/wiki/Crawler-transporter I know the ships are huge and it shouldn’t be feasible but it would be interesting to run the numbers. Edit. Actually if my math is rig…

What if we built Robert Bartini's Ground Effect Aircraft Carrier https://dj423fildxgac.cloudfront.net/fc6b316a-43b4-410f-8de6...

except as a cargo ship^H^H cargo ekranoplan which could cross land as well as ocean?

Re: Mexico building rail rival as water shortages drain Panama Canal

#98

Post by theluketaylor »

LargoLasskhyfv wrote: post #35
bilsbie wrote: post #5

Surely this is a mega project: but naively, what if we built say ten parallel railways 10 ft apart and moved cargo ships over the rails? Or this guy only needs to be scaled up 10X to do the job. Not outside the realm of imagination? https://en.m.wikipedia.org/wiki/Crawler-transporter I know the ships are huge and it shouldn’t be feasible but it would be interesting to run the numbers. Edit. Actually if my math is rig…

Something similar to this idea exists in Russia. But for larger river ships only, so smaller scale. There is a large dam, with generating station, downstream the valley is narrow, walls are steep. Differential to top of dam is large/high. Water locks impractical. So they've built something like a dock for the ships to enter, dock closes with ship inside, and is moved on cog rails up/downhill for a few miles, includin…

More for pleasure craft than commercial shipping, but I have taken a boat through the big chute marine railway in Ontario. Very cool experience.

https://en.m.wikipedia.org/wiki/Big_Chute_Marine_Railway

Re: Mexico building rail rival as water shortages drain Panama Canal

#99

Post by fragmede »

jodrellblank wrote: post #97
bilsbie wrote: post #5

Surely this is a mega project: but naively, what if we built say ten parallel railways 10 ft apart and moved cargo ships over the rails? Or this guy only needs to be scaled up 10X to do the job. Not outside the realm of imagination? https://en.m.wikipedia.org/wiki/Crawler-transporter I know the ships are huge and it shouldn’t be feasible but it would be interesting to run the numbers. Edit. Actually if my math is rig…

What if we built Robert Bartini's Ground Effect Aircraft Carrier https://dj423fildxgac.cloudfront.net/fc6b316a-43b4-410f-8de6... except as a cargo ship^H^H cargo ekranoplan which could cross land as well as ocean?

what's the energy expenditure for an ekranoplan vs a boat per mile?

Re: Mexico building rail rival as water shortages drain Panama Canal

#100

Post by halJordan »

reactordev wrote: post #46
intrasight wrote: post #31

Earlier quoted context omitted.

The economist article also mentioned just going north around Canada

So clearly they don’t know what they are talking about. Any sailor would tell you, you don’t go above and below 55 degrees. Granted these are steel container ships but the seas don’t care. What’s one or two lost containers of goods? They sit just below the water surface for the next vessel to crash into. The Panama Canal has two paths. Only one can be used for container ships. Even that has been at capacity for quite…

They're talking about after the ice melts friendo.
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