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by Schroedingersat 1102 days ago
Also false. LNG carriers are volume limited. Hence Q-Max vessels carrying about 100,000 tonnes vs bulk carriers of similar length carrying 400,000 tonnes.

Also I said useful energy. Depending on application, electricity is 1.5-5x as useful per joule.

Have you considered not just reaching for the stupidest possible lie on every occasion?

1 comments

LNG carrier are volume limited, a freighter carrying bulk lithium ion batteries is mass limited. Have you considered rethinking whether you misread a parent comment before accusing them of "reaching for the stupidest possible lie"? Let's re-read my comment:

> LNG is 20x the energy for a given volume than Lithium ion batteries. It's 50-60x as much energy for a given mass. The mass is the limiting factor for ocean transportation.

Liquid natural gas is less dense than water, so of course ocean transportation of it is not mass limited. Did it really no occur to you that I was referring to transportation of lithium batteries?

Anyway if you doubt that ocean transportation of lithium batteries is mass limited here's some math for you:

The biggest freighter has a volume capacity of 24K TEU and a mass capacity of 235,579 tonnes: https://en.m.wikipedia.org/wiki/Evergreen_A-class_container_...

TEU to volume conversion is inexact, but the most common 20' x 8' x 8'6" container is 33.2 cubic meters. This yields 33.2 * 24K = 796800 cubic meters for our Evergreen Ace.

The density of lithium ion batteries is more complicated. Sources say a 18650 battery weights 45g. The dimensions an 18650 are 18mm diameter base and 65mm length, yielding 16.54 cubic centimeters. So mass per cubic meter is 2720Kg, or 2.72 tonnes.

If we filled the Evergreen Ace with containers full of lithium ion batteries we'd have 2.72 tonnes per cubic meter * 796800 cubic meters would yield 2,167,296 tonnes versus our DWT of 235,579. We're almost an order of magnitude over weight if we fill out ship to the brim with batteries. Sure, there's nuances like packing efficiency (there's gaps between battery cells), but transportation of lithium ion batteries are overwhelmingly mass limited

> Liquid natural gas is less dense than water, so of course ocean transportation of it is not mass limited. Did it really no occur to you that I was referring to transportation of lithium batteries?

You were comparing LNG by mass to batteries by mass.

Now you're trying to pretend I was comparing volume to volume rather than a ship full.

So I guess the answer is no. You've never considered saying anything in good faith.

Again, let's look at the comment chain:

> A sensible 'normalised' comparison might be energy carried per displacement kilotonne or some such.

Defrost explicitly specified mass, "per displacemet kilotonne" To which you responded:

> Answering the original question, it's about 10-20x as much usable energy for the oil

10-20x is the ratio of energy density by volume, not mass.

I'm going to extend assumption of good faith, as it's easy to forget that there's two different measures of energy density. But yes, you did respond to someone asking about relative energy density by mass with the relative energy density by unit of volume. And the energy density by mass is indeed the limiting factor when shipping bulk lithium ion batteries, so this is a misleading (but probably not bad faith) figure to cite.

No, see I answered the actual question, which is oil. Which is mass limited. With how much energy would be available to do work at the destination.

You jumped to a ship two orders of magnitude larger and then insisted LNG carrying was mass limited, not volume limited.

I did not forget anything, merely pointed out the bizarre attempts to mislead.

> No, see I answered the actual question, which is oil. Which is mass limited.

Correct, and then you turned around and gave a figure for the relative energy density by volume, instead of mass (which would be a disparity 3-6x larger). And mass is the limiting factor for bulk shipping lithium ion batteries.

What are you even talking about?