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How to design a sailing ship for the 21st century?

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Re: How to design a sailing ship for the 21st century?

#41

Post by TotempaaltJ »

Animats wrote: post #33

A natural gas powered container ship would probably have lower emissions per unit of cargo moved than the proposed "eco" sailing ship, which has low cargo capacity by modern standards. The big problem with cargo ships from a pollution standpoint is that they run on really crappy "bunker oil C", which is about halfway between jet fuel and asphalt. Heavier than seawater. One of the biggest sources of preventable pollut…

Natural gas has its own issues https://www.theverge.com/2021/5/6/22422824/natural-gas-infra...

Re: How to design a sailing ship for the 21st century?

#42

Post by elihu »

krasin wrote: post #5

I hope we get rid of cargo ships that burn matter. But sails are too high maintenance to be scalable. Last year, as an experiment I've launched a tiny solar-powered boat ([1]). Ultimately, it was too small and underpowered only making ~900km ([2]) before dying. I hope to build a bigger drone boat next, hopefully with an ability to move up to 1 tonne of cargo. Apparently, it's possible, but (unfortunately) requires ve…

I wonder if electric ships could be a reasonable option? I don't have enough of the relevant numbers to do the math on whether a modern cargo container ship with some fraction of its mass dedicated to (perhaps) lithium iron phosphate batteries at about 150 watt hours per kilogram would be able to go any reasonable distance.

If we assume for the sake of argument that it's not enough for most reasonable-length routes, maybe if there was charging infrastructure at regular intervals that would help? I'm imagining for example a ship crossing the Pacific from the U.S. to China, but stopping in at Hawaii, the Marshall islands, and the Phillipines to charge. Maybe not even in a port; maybe there'd be power lines that run out to buoys that have the maritime equivalent of a DC fast-charger.

Also, one could imagine overhead lines being installed over the Panama and Suez canals. Ships could reach up with pantographs and charge their batteries as the traverse the canal.

The extreme case would be to have power lines that stretch from one continent to another, and ships cross whole oceans without ever unplugging. I'm not sure how that would work, exactly: floating cables? Cables that run along the sea floor, but the ships run an extension cord that drapes down to meet it? Lots of mechanical problems that would have to be solved.

Even with charging infrastructure only available in some places, if ships were configured with diesel engines that can take over when the batteries are dead, running off of batteries at least part of the time could reduce the fuel consumption by quite a lot.

Re: How to design a sailing ship for the 21st century?

#43

Post by elihu »

nradov wrote: post #22
krasin wrote: post #5

I hope we get rid of cargo ships that burn matter. But sails are too high maintenance to be scalable. Last year, as an experiment I've launched a tiny solar-powered boat ([1]). Ultimately, it was too small and underpowered only making ~900km ([2]) before dying. I hope to build a bigger drone boat next, hopefully with an ability to move up to 1 tonne of cargo. Apparently, it's possible, but (unfortunately) requires ve…

Nuclear may be part of our energy future, but security concerns and operating costs make it impractical to put reactors onboard civilian merchant ships. They can't afford to pay multiple armed security guards and trained reactor operators. Plus some countries don't even allow nuclear vessels into their ports. A more realistic solution would be to use land based reactors to manufacture carbon neutral synthetic liquid…

Rather than have one reactor per ship, perhaps you could have just a few ships with reactors? Regular electrically-powered ships would tether themselves to the reactor ship, and they'd cross the ocean in a large convoy. The tether would supply electrical power.

Re: How to design a sailing ship for the 21st century?

#45

Post by TheSpiceIsLife »

nradov wrote: post #22
krasin wrote: post #5

I hope we get rid of cargo ships that burn matter. But sails are too high maintenance to be scalable. Last year, as an experiment I've launched a tiny solar-powered boat ([1]). Ultimately, it was too small and underpowered only making ~900km ([2]) before dying. I hope to build a bigger drone boat next, hopefully with an ability to move up to 1 tonne of cargo. Apparently, it's possible, but (unfortunately) requires ve…

Nuclear may be part of our energy future, but security concerns and operating costs make it impractical to put reactors onboard civilian merchant ships. They can't afford to pay multiple armed security guards and trained reactor operators. Plus some countries don't even allow nuclear vessels into their ports. A more realistic solution would be to use land based reactors to manufacture carbon neutral synthetic liquid…

I'd be interested to see the numbers on this.

How much diesel-equivalent fuel could a 1GW nuclear power plant create in one year?

Here's my back of the envelope attempt.

1000MW * 0.9 capacity factor = 900

900 * 24 * 365 = 7,884,000MW

7,884,000 * 0.3 = 2,365,200MW electricity to liquid fuel efficiency[1]

2,365,200MW * 1000 = 2,365,200,000kW

2,365,200,000 / 10 energy content of 1L of diesel being ~10kWh

236,520,000L of diesel per year from a 1GW power plant.

Australia alone uses something like 33,000 megalitres of fuel per year (that's not all diesel, a lot of it would be petrol, but close enough).[2]

So Australia alone would need something like 140 x 1GW nuclear-to-diesel plants.

Did I do something wrong here? That seems like a lot.

This[3] says Australia has electricity generating capacity was 66.5 gigawatts (2017 number), so my 140GW estimate to cover Australia's transportation fuel requirements by electricity-to-diesel seems within the correct order of magnitude.

1. Semi-educated guess from https://en.wikipedia.org/wiki/Power-to-gas#Efficiency

2. https://www.abs.gov.au/statistics/industry/tourism-and-trans...

3. https://www.world-nuclear.org/information-library/country-pr...

Re: How to design a sailing ship for the 21st century?

#46

Post by jillesvangurp »

krasin wrote: post #5

I hope we get rid of cargo ships that burn matter. But sails are too high maintenance to be scalable. Last year, as an experiment I've launched a tiny solar-powered boat ([1]). Ultimately, it was too small and underpowered only making ~900km ([2]) before dying. I hope to build a bigger drone boat next, hopefully with an ability to move up to 1 tonne of cargo. Apparently, it's possible, but (unfortunately) requires ve…

I have a few reservations about nuclear on ships:

1) Nuclear reactors produce waste that needs long term storage. There are lots of hypothetical / partial solutions for this and a lot of nuclear waste sitting there in temporary storage patiently awaiting the day that this problem is actually solved. Adding more waste to that pile is not a great idea.

2) Ships go to sea. The sea is treacherous. Meaning that waste might end up at the bottom of the sea when ships sink.

3) Seas have pirates. E.g. the coast of Somalia is a security risk. Pirates and nuclear reactors are not a great combination. Pirates with Muslim extremist backgrounds even less so. Basically, nuclear powered boats are dirty bombs waiting to get hijacked.

Burning fossil fuels is the problem that needs solving. However, burning synthetic fuels is perfectly fine and engines don't really care how the fuel is created. Synthetic fuels can be produced using clean energy and then pumped in large storage tanks on ships; very much like is the practice today with normal fuel. It's the obvious future. Hydrogen is an obvious candidate for this and there are multiple companies working on this and a few prototypes already sailing. Add some solar and wind to the mix and you get some efficiency gains. Other synthetic fuels are feasible as well. Even diesel could be synthesized eventually. The main challenge is building the infrastructure that is going to generate enough fuel at reasonable cost.

There are a few drone ship operators out there. They are not used for cargo and quite small but it works. These guys (https://www.saildrone.com/) use solar and wind powered autonomous drone ships for months long operations.

Re: How to design a sailing ship for the 21st century?

#47

Post by algo_trader »

krasin wrote: post #24
patrickyeon wrote: post #17

Earlier quoted context omitted.

That's really cool! It looks like you're in the SFBA (or at least launched your boat from nearby), so are you familiar with Sofar and Saildrone? Do you have a way for people to follow what you're doing, or pitch in? I'd be interested in this (contact info in my profile).

Thanks for the kind words! Yes, I am in SFBA; I know about Saildrone; Sailbuoy, Liquid Robotics and a few other similar companies pursuing small data-collection drone boats. I didn't hear about Sofar yet - thanks for the link. As a full disclosure, the boat I launched was made under collaboration with Blue Trail Engineering ([1]) known for SeaCharger ([2]). All cool parts on the photo are from them; my parts were cam…

Do one these things last in Ocean waters? Sharks? Hurricanes? Random accidents ? Petty vandalism and piracy?

Can you hit 10 year life time if you use commercial grade components?

Re: How to design a sailing ship for the 21st century?

#48

Post by kisamoto »

Okay it's not cargo, but I've seen some innovative "eco" developments in the personal yacht space.

Take Daedalus yachts[0] for example, a USA built, lightweight (carbon fibre) sailing yacht with the aim of being zero emissions. They use a combination of solar, wind and hydrogen re/generation to get power for both the cabin and the drive system.

Perhaps a similar combination of technologies could be used to scale up commercial/cargo sailing ships?

[0] https://www.daedalusyachts.com/

Re: How to design a sailing ship for the 21st century?

#49

Post by frankbreetz »

krasin wrote: post #5

I hope we get rid of cargo ships that burn matter. But sails are too high maintenance to be scalable. Last year, as an experiment I've launched a tiny solar-powered boat ([1]). Ultimately, it was too small and underpowered only making ~900km ([2]) before dying. I hope to build a bigger drone boat next, hopefully with an ability to move up to 1 tonne of cargo. Apparently, it's possible, but (unfortunately) requires ve…

>I hope we get rid of cargo ships that burn matter.

What would be wrong with a hydrogen fuel ship or a biomass fueled ship?

Re: How to design a sailing ship for the 21st century?

#50

Post by throw0101a »

gabereiser wrote: post #6
krasin wrote: post #5

I hope we get rid of cargo ships that burn matter. But sails are too high maintenance to be scalable. Last year, as an experiment I've launched a tiny solar-powered boat ([1]). Ultimately, it was too small and underpowered only making ~900km ([2]) before dying. I hope to build a bigger drone boat next, hopefully with an ability to move up to 1 tonne of cargo. Apparently, it's possible, but (unfortunately) requires ve…

Larger sailing vessels (10m+) are actually moving towards solar + hydroelectric with lithium batteries (48v) to power electric engines and generators. Sailing with wind power uses the hydroelectric generators and solar. Motor sailing uses solar and you regen a little bit from hydro or a wind turbine. https://www.sailinguma.com/

Dan and Kika of Sailing Uma themselves recognize that this setup is not for everyone. Here's an interview with them on Sailing Ruby Rose on the subject:

* https://www.youtube.com/watch?v=xOAXi5huV1U

A better solution, for the time being, may be what Rebuilding Tally Ho is doing and use a hybrid engine:

* https://www.youtube.com/watch?v=xohxmwPfctg

He specifically chose a Beta Marine (marinized Kubota) diesel that has an electric motor/alternator connected to a 48V battery bank. If either the mechanics or electrics go, he can use the other. For short jaunts, like in and out of harbours, he can use the electric system to preserve fuel. The system has re-gen capabilities under sail.

More pricey though.

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