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Exploring the Cost and Feasibility of Battery-Electric Ships

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Re: Exploring the Cost and Feasibility of Battery-Electric Ships

#41

Post by akira2501 »

sitharus wrote: post #23
nwah1 wrote: post #11

Energy density of batteries is much lower than that of fossil fuels. Which means that the weight of the ships would increase. In addition to the high price of the batteries, potential risks of electrocution, etc. There are intermediate options. Moving away from diesel towards natural gas would dramatically reduce emissions (including sulfur emissions), while retaining high energy density.

LNG and LPG marine engines do exist, and are gaining popularity. The main issues are the price of gas fuel compared to marine diesel - which is the fraction too soft for roads and too viscous for other engines so is often really cheap - and safety considerations when retrofitting in to existing ships. Unlike diesel fuel, gas fuels are readily ignitable and present a suffocation hazard in enclosed spaces. This is solv…

> and safety considerations when retrofitting in to existing ships.

So, we're keeping the fire hazard, but adding a stored energy hazard in the form of compressed gas? All in a retrofit? This doesn't sound like a good idea for international ships.

> and most ports will have a significant supply available.

Are you sure about that?

Re: Exploring the Cost and Feasibility of Battery-Electric Ships

#42

Post by tonymet »

hwillis wrote: post #7
tonymet wrote: post #2

Ferry service in the Puget Sound (Seattle Area) has suffered due to delays with electric ferries. The state refuses to maintain their existing fleet. Every line has frequent delays, and the international route which was suspended for “a couple years” in 2021 is now delayed until 2030. The frustration people have with electric isn’t the technology – it’s the dogmatic commitment to technology that isn’t quite ready, ba…

It looks like that is a conversion and retrofit of ships that were already unmaintainable: https://washingtonstatestandard.com/briefs/conversion-of-was... Modernizing all the control systems etc is the nightmare. The ferries were already electric- all ferries are; they have diesel engines driving generators which drive electric motors. They still have the exact same generators running the same motors. The batteries a…

Sure but you have to think of the entire system which includes staff, training , charging infrastructure, power supply, possibly fuel for the charging infrastructure, backup/redundancy, maintenance, parts / distribution etc. An entire infrastructure network that had been operating for decades.

Diesel is more than just fuel, it’s an entire system.

Re: Exploring the Cost and Feasibility of Battery-Electric Ships

#43

Post by m463 »

nominatronic wrote: post #31

> The researchers analyzed US-flagged ships less than 1,000 gross tonnage, which includes primarily passenger ships and three types of tugboats. This is the buried lede. They are excluding basically all cargo shipping. - Very little of the shipping industry is US-flagged. Most commercial ships sail under flags of convenience such as Panama and Libera, because of their reduced regulations and costs. - Nobody carries c…

It could be the ships they are studying are the most inefficient, and pollute the most near people. Maybe they make the most sense to electrify. It could also be the only ones that can be forced to electrify by law.

Large container ships are pretty efficient and mostly stay away from populated areas.

Re: Exploring the Cost and Feasibility of Battery-Electric Ships

#44

Post by elihu »

nominatronic wrote: post #31

> The researchers analyzed US-flagged ships less than 1,000 gross tonnage, which includes primarily passenger ships and three types of tugboats. This is the buried lede. They are excluding basically all cargo shipping. - Very little of the shipping industry is US-flagged. Most commercial ships sail under flags of convenience such as Panama and Libera, because of their reduced regulations and costs. - Nobody carries c…

> Very little of the shipping industry is US-flagged.

That's true for international shipping, but for shipping between U.S. ports, the ships have to be U.S. flagged due to the Jones act.

https://en.wikipedia.org/wiki/Merchant_Marine_Act_of_1920

I agree though that focusing on small U.S. flagged ships is not very representative of shipping in general.

Re: Exploring the Cost and Feasibility of Battery-Electric Ships

#46

Post by taeric »

pingou wrote: post #38
AcerbicZero wrote: post #37

Earlier quoted context omitted.

Hah, if we're only going to talk only about tiny US ships, run them on whale oil for all I care. Seems to me the 80/20 here would be to attack the problem near the top of the stack, not the bottom. Those massive heavy fuel oil burning container ships that basically just smog the ocean 24/7 might be a good target for improvements; as well as just general code enforcement.

For now it seems the improvements (sulphur regulations) only made the situation worse, in term of climate change.

I'm surprised I don't see that discussed more. Too easy to slide into denialism? I thought there was a strong case a lot of the immediate ocean temperature changes these past few years was this. Which is not to deny climate change, but we should pay attention to all changes. Instead, I've seen more denial that cloud seeding could do anything.

Re: Exploring the Cost and Feasibility of Battery-Electric Ships

#47

Post by syncsynchalt »

hwillis wrote: post #3

Wow, this is a really good paper. Supplementary info is really great too- they get into details down to floating charging port stations as part of the infrastructure. Surprising how much demand is from tugboats. I have questions about how you'd safely hook up 5 MW connections, but it's definitely solvable.

Electric ferries have already proved out high-power dockside charging, though I'm unsure whether that's primarily marine or freshwater in practice.

https://www.stemmann.com/en/products/charging_systems/ferryc...

This company has designs that go up to 23MW @ 15kV, though I'm unsure what their largest actual installation is.

Re: Exploring the Cost and Feasibility of Battery-Electric Ships

#48

Post by sitharus »

akira2501 wrote: post #41
sitharus wrote: post #23

Earlier quoted context omitted.

LNG and LPG marine engines do exist, and are gaining popularity. The main issues are the price of gas fuel compared to marine diesel - which is the fraction too soft for roads and too viscous for other engines so is often really cheap - and safety considerations when retrofitting in to existing ships. Unlike diesel fuel, gas fuels are readily ignitable and present a suffocation hazard in enclosed spaces. This is solv…

> and safety considerations when retrofitting in to existing ships. So, we're keeping the fire hazard, but adding a stored energy hazard in the form of compressed gas? All in a retrofit? This doesn't sound like a good idea for international ships. > and most ports will have a significant supply available. Are you sure about that?

> So, we're keeping the fire hazard, but adding a stored energy hazard in the form of compressed gas? All in a retrofit? This doesn't sound like a good idea for international ships.

Indeed not, I haven't heard of any large cargo ship using gas fuel at sea other than gas carriers. I know that there are some dual-fuel ships, which use gas fuel in costal waters for emissions reasons, but they carry much less gas than would be required for a full voyage.

> > and most ports will have a significant supply available.

> Are you sure about that?

Ports have electric cranes (the big ones, not the straddle cranes), shore power supply for ships, bulk goods handling facilities, etc. They often have a high voltage (110kV+) supply. This won't be true everywhere, but it is common.

Of course it's not just a drop in process and it will be expensive to get all the new equipment in place.

My nearest port got their first electric tug two years ago and they documented what they needed to do. They did have to install a new substation, but their existing 110kV feeder lines have plenty of capacity, they already consume over 13GWh per year so the increase needed to charge the tug wasn't high.

I am ignoring the issues with charging battery-electric large cargo ships because the article did not consider those either.

Re: Exploring the Cost and Feasibility of Battery-Electric Ships

#49

Post by PlunderBunny »

m463 wrote: post #43
nominatronic wrote: post #31

> The researchers analyzed US-flagged ships less than 1,000 gross tonnage, which includes primarily passenger ships and three types of tugboats. This is the buried lede. They are excluding basically all cargo shipping. - Very little of the shipping industry is US-flagged. Most commercial ships sail under flags of convenience such as Panama and Libera, because of their reduced regulations and costs. - Nobody carries c…

It could be the ships they are studying are the most inefficient, and pollute the most near people. Maybe they make the most sense to electrify. It could also be the only ones that can be forced to electrify by law. Large container ships are pretty efficient and mostly stay away from populated areas.

Several of the diesel ferries that operate from Auckland harbour will be replaced with electric ferries next year and in 2026. Apparently ferries in Auckland carry only 6% of public transport passengers, but account for 20% of the public transport emissions [0].

0. https://at.govt.nz/bus-train-ferry/ferry-services/low-emissi...

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