Large electric motors, batteries and vehicles

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One Mackinac Island ferry in northern MI is having end-of-life diesel engines replaced with an electric propulsion system. Total project cost is around $6M, including a 1.5 MW shore power station. This project will be a pathfinder for electric conversion of 28 more vessels in the same fleet.

An unrelated project will add shore power facilities to docks in Sault Ste. Marie, allowing cargo ships to shut down diesel generators while dockside.

https://www.marinelink.com/news/503754
I think this is great news. I grew up in Duluth, MN at the western tip of Lake Superior. The Great Lakes are very vulnerable to pollution and being fresh water they are very important. Plus I've been on diesel ferries on Lake Superior and Lake Michigan and the lack of diesel smell and silence will be welcome to customers.
 
“EVs can rely on any energy source.”

That I think is the key message from the video.
 
There is an article in the latest AIAA "Aerospace America" about lithium-air batteries. I am not sure about the safety aspects of this concept. The energy density is much higher than ordinary lithium-ion batteries. It sounds like the scaling up and commercial prospects are years away. This is one of many articles on the internet
https://www.anl.gov/article/new-des...er-driving-range-compared-with-the-lithiumion
 
There is an article in the latest AIAA "Aerospace America" about lithium-air batteries. I am not sure about the safety aspects of this concept. The energy density is much higher than ordinary lithium-ion batteries. It sounds like the scaling up and commercial prospects are years away. This is one of many articles on the internet
https://www.anl.gov/article/new-des...er-driving-range-compared-with-the-lithiumion
National labs and colleges do beautiful things but it’s hard to say which ones of their projects will ever scale. That’s the whole point of R&D. We need labs like those to explore things that are still too risky for private enterprise and to go beyond what companies can look at today.
 
If you'd rather stick to tech than implementation, I can delete the post. We had a battery project fall through. Interestingly, it wasn't technology, price, or availability that was the issue; it was concerns about whether we could get regulatory approval on alarms and fire protection requirements without delaying the overall build process. The owner is keeping options open to swap out the diesel generator for a battery in the future.
 
IMO, battery tech or chemistry is not holding back EV penetration. I mention EV because that will be the tech/cost driver all other stationary battery use cases. Current tech meets the need. Costs have to come down and that won't happen (near term) by new innovative battery tech that hasn't scaled. Cost will come down with manufacturing tech of current battery tech.

Range anxiety currently is keeping us in the flatter beginning part of the S-curve. We well get to the inflection point of the S-curve as manufacturing costs come and range anxiety wanes. The latter is a process and need to be patient for it. I think that flat part of the S-curve will persist longer than people think.
 
If you'd rather stick to tech than implementation, I can delete the post.
I lost track what this refers to. But just in case, maybe this is relevant: twigs are easier to remove than stumps, but preventing them altogether is even easier. I think it's nice to have a battery-only place. It's the only one in here.

IMO, battery tech or chemistry is not holding back EV penetration. I mention EV because that will be the tech/cost driver all other stationary battery use cases. Current tech meets the need. Costs have to come down and that won't happen (near term) by new innovative battery tech that hasn't scaled. Cost will come down with manufacturing tech of current battery tech.
I agree with that. It is also very much what Tesla is doing.
 
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I lost track what this refers to. But just in case, maybe this is relevant: twigs are easier to remove than stumps, but preventing them altogether is even easier. I think it's nice to have a battery-only place. It's the only one in here.
It's mostly that there have been arguments on this thread (heck, I've participated in them!) that this is intended as a discussion place for what's possible and what's new rather than roadblocks or problems. I'll stop this side excursion unless there's a groundswell of support for more info.

The twigs vs. stumps question is an interesting one once you get into implementation. One of the questions was on the fire protection system and whether the battery cooling system was sufficient to meet fire protection requirements. It would have taken ~6 months for the Coast Guard to make that decision (and it might have been "no"). Similarly, if the cooling system wasn't adequate, then dry chemical would have been the preferred extinguishing agent. Oops, there's no USCG-approved fixed (as opposed to handheld) dry chemical fire extinguishing systems. That would have been another 6 months to a year to get approved. I don't fault the USCG for taking time with their reviews--fire safety of lithium batteries is a real issue; it just doesn't fit into the 11 months remaining before the boat is delivered to the owner. Anyway, what looks like a twig (just add a fixed fire extinguishing system) can end up being a stump if you don't fit neatly into the rules as they exist now.
 
One of the questions was on the fire protection system and whether the battery cooling system was sufficient to meet fire protection requirements. It would have taken ~6 months for the Coast Guard to make that decision (and it might have been "no"). Similarly, if the cooling system wasn't adequate, then dry chemical would have been the preferred extinguishing agent. Oops, there's no USCG-approved fixed (as opposed to handheld) dry chemical fire extinguishing systems. That would have been another 6 months to a year to get approved. I don't fault the USCG for taking time with their reviews--fire safety of lithium batteries is a real issue; it just doesn't fit into the 11 months remaining before the boat is delivered to the owner. Anyway, what looks like a twig (just add a fixed fire extinguishing system) can end up being a stump if you don't fit neatly into the rules as they exist now.

In addition to proper cooling and power management, the battery packs can incorporate fire suppressants, and they can be in sections and separated from each other. Raw material purity also matters. Many resources in here, maybe I'll register for some of these to know more:

https://chargedevs.com/sessions/
 
In addition to proper cooling and power management, the battery packs can incorporate fire suppressants, and they can be in sections and separated from each other. Raw material purity also matters. Many resources in here, maybe I'll register for some of these to know more:

https://chargedevs.com/sessions/
Most of the marine cell manufacturers use some kind of running water to cool the batteries to prevent them from going into runaway, or at least protect the ones around a cell running away. This manufacturer was doing a two-fer and using that water to cool the batteries. I like the plan; it just ran afoul of a "thou shalt not" in the USCG regulations. Getting around that takes a bunch of time.

More to the goal of this thread, it's been interesting to see presentations from different manufacturers on how they arrange their batteries. The group above had cells set up like folders in a file cabinet, with cooling going around the perimeter. There are other ones that are a large cell the size of a loaf of bread.
 
More to the goal of this thread, it's been interesting to see presentations from different manufacturers on how they arrange their batteries. The group above had cells set up like folders in a file cabinet, with cooling going around the perimeter. There are other ones that are a large cell the size of a loaf of bread.
I'm not up-to-date on the pros and cons of each configuration and mostly use Tesla as a reference. Their main concern appears to be to get as many cars on the road as quickly as possible. So they chose 4680 cylinders because of ease of manufacture and their bigger size means they don't need as many units, so production is also quicker.

Hopefully, I'll also get to watch presentations on other configurations. I can be called to interact with EV engineers at any time, but also in other techs, so I enjoy using spare time to jump haphazardly from one lily to the next to stay sharp ... -ish. 🐸
 
I'm not up-to-date on the pros and cons of each configuration and mostly use Tesla as a reference. Their main concern appears to be to get as many cars on the road as quickly as possible. So they chose 4680 cylinders because of ease of manufacture and their bigger size means they don't need as many units, so production is also quicker.

Hopefully, I'll also get to watch presentations on other configurations. I can be called to interact with EV engineers at any time, but also in other techs, so I enjoy using spare time to jump haphazardly from one lily to the next to stay sharp ... -ish. 🐸
I'll see your bigger size and raise you 500x900x250mm (rounded) per cell like these guys. :D They're running around 500-600 AH/cell. The maritime world really wants cabinet to container size units where you can reasonably easily replace cells. While we like light weight and high power density, modularity and particularly fire safety are issues you don't have to worry about to the same extent on land. In a car, you can run away from the fire. On a boat, that's a lot harder.
 
I'll see your bigger size and raise you 500x900x250mm (rounded) per cell like these guys. :D They're running around 500-600 AH/cell. The maritime world really wants cabinet to container size units where you can reasonably easily replace cells. While we like light weight and high power density, modularity and particularly fire safety are issues you don't have to worry about to the same extent on land. In a car, you can run away from the fire. On a boat, that's a lot harder.
I bet. I don't think about boats very much. But like aircrafts, if I get a chance to hop in an e-boat of any kind, I'll be wrapped up in a wetsuit and on board in no time, ready to jump off at the slightest whiff of ... let me do quick search here ... aha! ... fluoride gas. 😁 (until they're as standardized and known to to be as safe as cars that is)
 
I bet. I don't think about boats very much. But like aircrafts, if I get a chance to hop in an e-boat of any kind, I'll be wrapped up in a wetsuit and on board in no time, ready to jump off at the slightest whiff of ... let me do quick search here ... aha! ... fluoride gas. 😁 (until they're as standardized and known to to be as safe as cars that is)
It's not quite that bad. But it does tell you why the USCG is conservative (in the engineering sense) about shipboard battery installations. The key is not so much preventing a fire, but making sure that things don't get worse if there is a fire. The regulations more or less assume that a fire will break out in the batteries and then make sure that the disaster gets contained. Of course, they also try to keep a fire from starting, too. As safe as a car? I'm not really sure--it's kind of apples and oranges. Standardized is highly unlikely. A quirk of the US maritime industry is that everybody wants their boat to be a little different from the other guy's boat. So we dust off the plans and make it "exactly the same except". There are a solid half dozen different battery manufacturers (more if you include vaporware), though that herd will likely get thinned a little bit.

There was a pretty spectacular fire in a hybrid tug back in 2012. The crew extinguished the fire and got off the boat OK with a minor case of smoke inhalation (no idea if that included HF or not). That likely set the US maritime industry's adoption of battery technology back by 5-10 years.
 
It's not quite that bad. But it does tell you why the USCG is conservative (in the engineering sense) about shipboard battery installations. The key is not so much preventing a fire, but making sure that things don't get worse if there is a fire. The regulations more or less assume that a fire will break out in the batteries and then make sure that the disaster gets contained. Of course, they also try to keep a fire from starting, too. As safe as a car? I'm not really sure--it's kind of apples and oranges. Standardized is highly unlikely. A quirk of the US maritime industry is that everybody wants their boat to be a little different from the other guy's boat. So we dust off the plans and make it "exactly the same except". There are a solid half dozen different battery manufacturers (more if you include vaporware), though that herd will likely get thinned a little bit.

There was a pretty spectacular fire in a hybrid tug back in 2012. The crew extinguished the fire and got off the boat OK with a minor case of smoke inhalation (no idea if that included HF or not). That likely set the US maritime industry's adoption of battery technology back by 5-10 years.
For a cargo ship, does anyone have to be on board at all? Why not control it remotely from a smaller escort ship that's proven safe and can easily and quickly move away. The cargo ship's captain could sit in a simulated cockpit on the escort ship (the escort ship having its own captain). Just have the crew in a separate, safe, more maneuverable ship.
 
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For a cargo ship, does anyone have to be on board at all? Why not control it remotely from a smaller escort ship that's proven safe and can easily and quickly move away. The cargo ship's captain could sit in a simulated cockpit on the escort ship (the escort ship having its own captain). Just have the crew in a separate, safe, more maneuverable ship.
This is the $10 billion question running in maritime circles right now. There's actually no real need or benefit for the watchstanders to be on a nearby boat--that probably doesn't save time or money. For most of the trip across the ocean, control by satellite would be fine as long as you could get bandwidth to transmit radar data up to a land-based control station. With constellations like Starlink, that's much more possible than in years past. In most cases, the larger ship is safer, even if it is less maneuverable.

For 99.99%+ of transits, everything would be fine. It's handling that other fraction when things go wrong that is the issue. Think of how bad it got when the very small error rate hit the Suez Canal and the Ever Given got stuck. Some other issues:
* Every so often, things go badly wrong. A ship catches fire, steering goes out, engine breaks down, etc. You are far, far more likely to save the ship and cargo if you have a crew on board.
* The crew does a significant amount of maintenance when they're on board. For example, virtually all commercial boats have enough redundancy in their generators to have one down for maintenance. The crew can do nearly any maintenance needed by taking that genset down and just using the others. Multiply that by winches, deck equipment, painting, etc. and there's a lot that happens at sea. It would be hard to shoehorn that into maintenance during a port visit.
* You will need a crew on board when you dock to handle mooring lines and manage machinery, not to mention having a harbor pilot on board. Getting them on and off is difficult and dangerous, particularly if you have to do that offshore.
* There are some things that people do better that machines. There's pattern recognition, and sometimes a gut feeling that something's not quite right. That can be as small as an increase in the roll period indicating flooding in a compartment. While that data can be captured in an automation regime, it's hard to replace the feeling you get for a boat and how it normally behaves.

As you probably saw in the self-driving cars thread, I'm somewhere between a skeptic and a pessimist on the promise of automation to replace people, at least with current technology. There are definitely answers to all of these concerns, but self-driving ships are still in the very small boat demonstrations phase.
 
... There's actually no real need or benefit for the watchstanders to be on a nearby boat
What about security? Just how many pirates are there out there? Would they be more tempted if the ship was autonomous?

* The crew does a significant amount of maintenance when they're on board. For example, virtually all commercial boats have enough redundancy in their generators to have one down for maintenance. The crew can do nearly any maintenance needed by taking that genset down and just using the others. Multiply that by winches, deck equipment, painting, etc. and there's a lot that happens at sea. It would be hard to shoehorn that into maintenance during a port visit.
* You will need a crew on board when you dock to handle mooring lines and manage machinery, not to mention having a harbor pilot on board. Getting them on and off is difficult and dangerous, particularly if you have to do that offshore.
I see.

... I'm somewhere between a skeptic and a pessimist on the promise of automation to replace people ...
I don't see it as a promise, I rather see it as something to aim for. We'll never know how far we can go unless we try, just as any other technological progress. Comp. Sci. professors have to keep busy.
 
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I don't see it as a promise, I rather see it as something to aim for. We'll never know how far we can go unless we try, just as any other technological progress.
Every time I see a human forced to do something machines are good at, I get a little sad. There's so many things only humans can do, stop wasting them!
 
What about security? Just how many pirates are there out there? Would they be more tempted if the ship was autonomous?
Piracy is a very localized business. There's definitely hot spots in the Gulf of Aden (entering/leaving Suez) and the Straits of Malacca (leaving Singapore toward Africa). There's probably places in the Philippines that are also not very nice. That said, several navies patrol those areas fairly aggressively to keep ships safe. In some ways, the task of defending against piracy would be easier with an autonomous ship. Sure, the pirates could get on board, but they wouldn't be able to get in a door to anything critical if there aren't any doors.
I don't see it as a promise, I rather see it as something to aim for. We'll never know how far we can go unless we try, just like any other technological progress. Comp. Sci. professors have to keep busy.
Autonomous control is going ahead by leaps and bounds. It will get there eventually; it's just in its infancy now. The folks who say that all ships will be autonomous in 10 years and the folks that say ships will never be autonomous frustrate me equally. Reality will be in the middle somewhere. There may be a middle ground where the technology is there but it doesn't make financial sense to automate some ships.
 
Every time I see a human forced to do something machines are good at, I get a little sad. There's so many things only humans can do, stop wasting them!
There’s still the question of cost. Batteries and autonomy are still not cheap, but developing competitive robots is an interesting challenge that will provide options for some.
 
There’s still the question of cost. Batteries and autonomy are still not cheap, but developing competitive robots is an interesting challenge that will provide options for some.
I am aware. "The machine is more expensive than you, so get back in there" is the bit that makes me sad.
 
I am aware. "The machine is more expensive than you, so get back in there" is the bit that makes me sad.
It would make me less sad if our economic system allowed the people whose jobs are displaced by automation to do other things and still not starve. But that's a whole 'nother conversation that would last about half an hour before getting locked by mods here, for good reason.
 
I am aware. "The machine is more expensive than you, so get back in there" is the bit that makes me sad.
It depends on the machine, the person and the task or job. Not simple.

I’m starting to worry a politician will drop by and carry us in a ditch. Back to batteries I think.
 
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