Launch HN: OutSail (YC W23) – Wingsails to reduce cargo ship fuel consumption

[jmoorebeek]

Hi HN! I’m Joseph, and along with Arpan and Bailey we are the founders of OutSail Shipping (https://outsailshipping.com/). We’re building a sail the size of a 747 that rolls up into a shipping container. When deployed, it will generate thrust from the wind to reduce the fuel consumption of a cargo ship. An array of these devices will reduce fuel consumption on ships by up to 20%. These sails are easily stowed and removed to cause no interference with cargo operations. Here’s a short video showing our prototype: https://www.youtube.com/watch?v=VUpVqzpym54.

Sails powered ships for millennia; but then the convenience of energy-dense fuels displaced sails. As ship speeds eventually exceeded wind speeds, the consensus became that sails had no place in shipping and were relegated to hobbyists and sport. Fast forward a century and a half, and maritime shipping, like all other industries, is facing a reckoning to mitigate the greenhouse gasses produced by their activities.

The International Maritime Organization (IMO) has introduced new regulations which use a vessel’s Carbon Intensity Indicator (CII) to grade ships. This grading scale becomes more aggressive over time, and any ship with a poor grade must take corrective action. The corrective actions can be as non-invasive as reducing speed (aka: slow steaming) or as extreme as a retrofit to use a different, cleaner fuel source. This costs millions and takes a ship out of commission for months, and it’s difficult to ensure your (now more expensive) fuel is available at every port of call. Ship owners are hedging their bets that slow steaming will dominate their future, with ship order books full to reflect the increased capacity needed when containers take 20% longer to cross the ocean.

Or option three. There is sufficient wind on the ocean to power the entire shipping industry, if you’re willing to grab it. Wind Assisted Ship Propulsion (WASP) devices can be used as a corrective action to improve a vessel’s CII rating, without reducing ship speed or changing the route. In other words, a return of sails.

We are hardware engineers with over two decades of experience between us, working at Tesla, SpaceX, JPL, Relativity, and some startups. The idea for OutSail came from Arpan and Joseph getting coffee after work one day. When we asked each other “What would you do if you weren’t building satellites?” maritime cargo came up from both sides; Arpan from having studied the industry for opportunities to reduce emissions, and Joseph from a love of hydrodynamics and maybe too many sea-shanties. Bailey and Arpan, meanwhile, had been looking at working on bicycling infrastructure. What brought the three of us together was actually a Dungeons & Dragons game where we realized we made a good team! We settled on OutSail as a good fit for our hardware hacking mentality, trading in our druids staffs for spanners.

Aerodynamically, sails are simply vertical wings. Wind blowing across the vessel causes the sail to generate lift and drag, and the resultant vector has some forward component to pull the ship through the water. However, if the wind comes from an angle too close to the direction of travel, there is no thrust. As an added complication, the sail only sees the relative wind. If the ship travels faster, the wind will appear to come from closer and closer to the direction of travel, even if the true wind is coming from perpendicular to your course! Despite this, standard sails can still produce forward thrust as long as the wind is at least 20 degrees off from directly in front of the vessel. This is how our sails can still save power, even on a fast moving vessel.

There are many sail technologies out there. A common question we get asked is “Are you going to use flettner rotors/suction airfoils?”. Both of these technologies use power supplied by the ship to increase the lift produced by a surface; rotor-sails spin, and suction airfoils…suck? Each of these have a place, especially at low vessel speeds. But our customers ask us for a solution that works for container ships cruising at the relatively high speed of 22kt. At these speeds, the relative wind is almost always ahead of you, so lift/drag becomes more important. Powered sails suffer from poor lift/drag, both from the high induced drag from very high lift coefficients, and system losses from drawing on ship’s power. So no we are not going with flettner rotors/suction airfoils. While they are the new exciting technology on the block, if you factor in their power usage and high drag ratio, they are just not as practical as a simple sail.

So now that we’ve given a general summary of sailing, it’s time to explain how a 747 wing will ever fit inside a 9ft tall cargo container. It’s simple really: imagine a tape measure. In a tape measure a thin, flexible strip of metal is wound into a spiral. Then, when the metal is uncoiled, it naturally returns to its original shape. That’s exactly how we plan to make our sails. The skin of our sail or the inner spars (we haven’t finalized our design) will be made of tape measure like material (2mm thick steel) and the wing will be able to extend out of the cargo container. The video in the first paragraph explains this in a bit more detail.

By fitting our sail into a cargo container we allow for our device to be installed on any cargo ship right at port. Remember how we mentioned that some shippers are ordering a lot more ships and some ships are getting retrofitted with new fuel? Well, shipyards are backed up for the next 5 years. By making a device that requires no shipyard to install, not only will we drastically outcompete other retrofit WASP companies in terms of deployment cost, but we will be the only company with a product shippers can put on their ship without a multiple year wait time.

Do you have any interesting stories around sailing or wind tech? We would love to hear your ideas, experiences, and feedback on any and all of the above!

[wpietri]

As the maintainer of a cargo ship tracker [1] and as somebody whose sailing career started and ended with sinking [2] a J/22 sailboat [3], I can only salute you. This is clever, bold, and ambitious. How do we keep track of your progress? I looked for a blog or mailing list, but I didn't see one.

[1] now at https://sfba.social/@sfships; formerly at https://twitter.com/sfships

[2] They said it was unsinkable, but as a software developer clearly I'm more talented than the norm.

[3] https://en.wikipedia.org/wiki/J/22

[ArpanRau]

Follow our linkedin! I'll post there when I can :)

https://www.linkedin.com/company/OutSail-Shipping/

[trillic]

What happened? Long knock down and a hatch glass failure? Or a failure to secure the hatch glass entirely?

[trillic]

Awesome to see this on Hacker News, I love whenever we get sailors on here. I have tons of questions.

Why steel? Durability I assume? Have you modeled using a textile?

Do you have load sensors throughout the wing? Anemometors?

How active is the trimming? Is it just a single axis of rotation or do you have the ability to adjust the leech and luff shape? If so do you have the ability to adjust both the leeward and windward skins? Or just the windward? 2mm steel seems like it has a decent amount of play at that scale? Have you built any bigger scale models with steel? Feels to me like iteration time would take a significant hit playing with steel instead of cloth?

As consistent as these ships are with their speed under motor, the apparent wind will be all over the place. Could see apparent from 50+ on the nose to 5 knots from dead astern. Do you intend to have a fixed set of optimal wind velocities and trim settings? Or want to make something that is usable and automatic in anything but the most violent of breezes?

How much of the bill-of-materials is custom and how much is off-the-shelf type components and structural bits? Any custom composite parts or fairly off the shelf steel tubing, bar, and such?

Also are you hiring?

[jmoorebeek]

We're looking at steel partly for durability, but also if we're going to be rolling up the sails a lot then fatigue limits become a lot more important. Cost is key too - I'd love to make this from CF, but price goes way up.

For load sensors, we're thinking strain gauges and pressure sensors to measure wing surface pressure and use that for live feedback. Anemometers might be mounted on the top of the wing, but more likely we'll use a master anemometer at the bridge to send info to the entire array.

For the wing shape, we're currently looking at a symmetric airfoil with fixed ribs inside for strength, so not able to actively change the camber, but we are looking at the ability to do wing warping to change the overall shape of the wing. We are still working to get our first data from on the water, so no good answers on the trim other than we want to make this as automatic and turnkey for the ship master as possible. We're quite early in the design still, though, so don't yet know where the limits of the technology are. Likewise, no answers on BOM and sourcing for you. However, we do plan to start hiring after our seed raise, so feel free to contact us through our website!

[roter]

I know zero about how containers are tied down but the gust forces on the sails that I saw in the video are going to be enormous. Have there been some simple checks on the righting moments on the container and how it transmitted to the containers below and finally to the deck? One benefit of the design is that you can "reef" in bad conditions (hopefully really, really quickly) and perhaps still get some benefit.

Have you done any weather routing calcs to see what the angle of attack for the big ship lanes? Perhaps an integrated trip cost-benefit?

Also, you might not want to use the WASP acronym and stick with just "wind-assisted propulsion". The wind industry will immediately think of the WAsP software [0].

[0] https://www.wasp.dk/

[ArpanRau]

Appreciate the acronym check! That's a great point.

Our design evolved out of a routing/performance analysis software that we run on historical weather data. Angle of attack and trip cost-benefit varies per lane. In general transpacific and transatlantic have amazing winds, with other routes performing well but not at well.

We've done the excel-level analyses on container loads and wing buckling forces. It all checks out. There is a combined-load case at 15deg of roll with heavy containers and heavy winds that's zero-margin, but as you said we can reef when required. Reefing will likely be single-digit minutes, but we can also feather (0 angle of attack) much more quickly.

[jmoorebeek]

I agree, the roll moments are a huge design challenge! We're looking at multiple avenues to bring those loads down to the deck: - The double wide container already has a longer lever arm to provide righting moment - We plan to incorporate load spreaders (similar to a crane) which can further extend the footprint to the adjacent container stacks - We are designing in tethers which automatically drop down to the deck level and get lashed down by a deckhand during installation, which provide additional tension support.

Bailey has written a routing software which we use to send virtual ships on crossings (for instance Trans Pacific), incorporating historical weather data. Even with no change in route or vessel speed, we can see benefits.

[jakubmazanec]

AFAIK this is what is most associated with WASP acronym: https://en.wikipedia.org/wiki/White_Anglo-Saxon_Protestants

[polar8]

If you go with WAP you can hire Cardi B as your celebrity spokesperson!

[Gwypaas]

I would be cautious about the twisting loads on containers. The side forces will be huge, especially in a swell. Then add mechanical parts that must work in an incredibly hostile environment, and lastly, add on the north Atlantic in the winter, and you are in for a bad time. Ships losing containers due to stacks collapsing happens very frequently, without any extra forces.

https://alsum.co/wp-content/uploads/2021/04/Perdida-de-conte...

Look at a purpose-built sailship from the age of sail in a north Atlantic storm. It is a rough ride.

https://www.youtube.com/watch?v=Y7RABaByP_8

Another attempt in a similar fashion is the Oceanbird concept by Wallenius Wilhelmsen, but that means building the vessel from the ground to handle the forces and that over-head loading and unloading is not possible, thus the aim at RO-RO ships.

https://www.theoceanbird.com/

With one vessel already ordered:

https://www.walleniuswilhelmsen.com/news-and-insights/highli...

Personally, as a commercial sailor and software engineer, this container approach screams of VCs throwing money at commercial shipping without understanding the industry. Profit margins are non-existent and are already hugely optimized with possibilities for specialized solutions. This wing sail will have to compete with synthetic fuels without increasing the cost due to crewing requirements.

[ArpanRau]

Yep, supporting the moment from the wing via containers is the biggest structural concern. The containers are strong enough in most sea states, with reefing/feathering required in heavier winds and seas. We will stow the sail long before it encounters conditions like the ones shown in your video.

Oceanbird is awesome! The trouble is that overhauling the entire industry with new-built ships would take too long to make a meaningful climate impact, and be extremely expensive (not to mention that their approach only works for ro-ros).

Synthetic fuels will compete with aviation for the green hydrogen supply (needed to make methanol/ammonia/green hydrocarbons) and are expected to cost 2-3x what current fuels cost. This net makes our fuel cost savings case even stronger.

Industry insiders generally already know that there's really no good cost-saving decarbonization solution, and that decarbonizing fast is a hair-on-fire problem for owner/operators. The barriers standing in the way of most wind-assist devices are: poor ROI, shipyard availability for retrofits, risk to shipwoner (capital upfront), and that they don't package on containerships. We solve all these problems by using a large, efficient wing and depending on the container load path. There are technical problems to solve, but the fundamental physics works.

[RhodesianHunter]

This is clearly intended to supplement, not replace, the ship's existing power source.

You would fold these down rather than trying to ride out a swell with them up. They go out of they way to clarify how easily these can be furled and unfurled.

[carabiner]

Everyone's forgetting that this is just like a jetliner wing. Huge forces, harsh environments, long lifespan... this is how commercial airplanes are designed, and one of the founders is a professional aerospace engineer who worked at Tesla.

[roflyear]

Well, you don't have to run it in those conditions.

[sourcecodeplz]

It's never gonna work for a multitude of reasons like you said. Usually I'm not pessimistic but this really seems like: we have an idea, make a video, post it on a site, ask questions later.

[jpm_sd]

Agreed on all counts. "Mirage" is the perfect name for this product.

[chrisweekly]

I love literally everything about this idea and origin story. I care about climate change, I've lived on sailboats, I'm a software engineer, I've worked for and with startups for over 20 years... and somehow this line:

"What brought the three of us together was actually a Dungeons & Dragons game"

is the best part.

Feel free to hit me up (contact info in my profile) if you need a pep talk or intros to different circle of potential investors or friendly advice about web performance. Otherwise I'll be following your story and cheering you on from the sidelines.

[theflyingpigeon]

Shipping is responsible for 3% of global emissions. Let’s say this solution worked (which it probably won’t), it would be used in a small percentage of vessels, and only used in an even smaller number of voyages/parts of each voyage. The difference for the climate is basically zero.

[joshuabaker2]

This looks amazing! Wind power is totally underutilized in the shipping industry, I've been waiting for something like this for ages.

I used to be part of a team back in university making autonomous sailboats [1] and one of the things that I was surprised by when working on this was that there are a TON of hurricanes out in the middle of the ocean (we were working to build it to cross the Atlantic). We built a system to take in weather prediction data to try to avoid hurricanes, but we were building a relatively tiny boat—do large shipping vessels do this as well? I'd assume they can sail through pretty bad weather. If so, do you have ways to lower the sails easily to protect them?

Additionally, do you have any software to help inform the vessel operators how to best sail into the wind or are the net savings not worth it considering most of the propulsion is still coming from fuel-based sources?

Overall, this is super exciting and best of luck!

[1] Now at (https://www.ubcsailbot.org/)

[jmoorebeek]

Lowering the sails will be critical to safe operation in bad weather. The deployment process will be easily reversible, so that within a few minutes you can go from full sail to fully stowed (or any place in between), likely with emergency settings to bring the sail down faster. We don't want to limit the weather a ship would sail in without diversion, but instead just make use of reasonable winds when they are present. We certainly will want to make future software for route planning assistance, but our first step will not require the ship to change course or speed to see benefits of the sails. It's certainly worth it over all to follow the wind, but for ease of adoption that can come later.

[schimmy_changa]

Large cargo vessels do try to avoid bad weather, even though they can sail through most of it. It's a crew happiness, risk, and loss avoidance concern (knowing these companies, probably mostly the latter two!).

I was on a cargo ship in the pacific which diverted into the Bering Sea to avoid some weather instead of skirting just south of the Aleutian Islands as planned. The captain gots orders via satellite from a land crew that's crunching the numbers of risk vs extra fuel costs at all times for the fleet. The first mate was frustrated by how this all works. He said (English not being his first language): "This is terrible! We never get to decide anything for ourselves. We are like Muppets!". I think he meant "puppets"...

[carlosjobim]

> Wind power is totally underutilized in the shipping industry

The shipping industry was 100% wind powered, with very mature technology developed and tried during centuries, and thousands upon thousands of experts in the area. Why do you think the whole industry switched to engines?

[keizo]

Did you work with Greg Wong?! I worked with him after he graduated and heard quite a bit from him. Awesome project. :)

[ilrwbwrkhv]

This is amazing and a great panacea for the pain caused by the ai copycat products I have been seeing flooding YC.

New breakthroughs in transportation is the need of the hour.

One of the reasons the world is teetering on a recession right now is there has been not a lot of physical changes to the world around us to create new worlds which software can then eat again.

Projects like this then, give me a lot of hope.

[fourseventy]

With the relative wind angle mostly being dead ahead because of the engines, this means that the vessel will effectively be sailing a close hauled course. When sails are trimmed for this heading, most of the force generated by the sail is perpendicular to the direction of the vessel. In normal sailing vessels this perpendicular force is converted into forward velocity with a keel. Without a keel your sailing ship will just drift sideways when attempting to sail a close hauled course. I'm assuming that giant shipping container ships don't have a keel, so how will these sails generate effective forward velocity for the ship and not just drag the ship horizontally off course?

[jmoorebeek]

While a container ship doesn't have a keel per-se, it does have about 200m of flat plate length sticking into the water. At small angles, that flat plate can actually have a decent lift to drag ratio. Historic sailing vessels also made do without a modern wing-keel, so our current plan is that the container ship can crab into the wind by less than a degree to produce all of the side force required to maintain a steady course.

[swyx]

F** yeah, YC startups doing things in the real world. loving this trend, i know nothing about your field but you inspire me. lets go green and make green.

[polar8]

russ hanneman is that you?

[UberFly]

I picture you dancing on stage with Ballmer.

[barbegal]

I would love to see a simulation of the forces involved here because I just can't see it adding up. A 60m tall sail introduces some really significant torque which may well be handled by the double container but how does that force get transferred from the sail to the container?

The design requires a lot of moving parts and the reliability of the system appears to be safety critical. If the sail can't be reefed in high winds then it risks serious damage to the ship. And if it can't be reefed when entering port then you can't dock the ship. Until the technology has been proven to be extremely reliable I can't see any operator risking installing it.

[andrewfong]

I have no sailing or nautical or any relevant experience, so apologies if this is obvious, but what keeps the sail from getting blown off the ship?

My understanding is that the container is lifted and placed on top of a typical container vessel. And containers do fall off ships from time to time. Adding a very large sail to the container makes it easier to blow off. Is whatever the standard mechanism is for securing containers to ships sufficient here?

[bkor]

> Is whatever the standard mechanism is for securing containers to ships sufficient here?

Not in the slightest. Containers are secured by lashing them. But that's just the one level, mostly. Then after that it is twist locks. There are enough pictures of containers being ripped apart by the sea. Or stacks entirely damaged. Containers are made from steel, loads of people tend to assume they're indestructible. Or that they can hold way more weight than they can (scrapped metal people).

[jillesvangurp]

I love ideas like this. I used to sail a bit in school vacations when I was young and feeling the raw power of the wind in your hands really drives home how practical it is to use wind. For thousands of years this is how people traveled the world. Most of the modern world was mapped and discovered long before steam power was invented. Using sail boats almost exclusively.

Of course steam power and later combustion engines replaced wind in the last 150 years or so. However a few things have changed since then that makes concepts like this viable again and worth exploring.

1) Material science has progressed, a lot. A modern wind foil compared to a canvas sail from a few centuries ago is not a fair comparison. Modern sail boats vastly out perform anything that was common before steam boats showed up. Lighter, faster, cheaper, etc.

2) Sail boats used to require a lot of people to operate them. Modern sail boats can be operated by a lot less people and solutions like this could feasibly be used on autonomous ships even. Automation and fine control assisted by lots of sensors and actuators are a game changer.

3) Before steam boats, navigation was primitive and we had no reliable way to predict weather. Ships would just drift out on the open ocean for weeks and journeys could take months. These days we have satellites. We know weather patterns and navigation is a solved problem. Also we've mapped ocean currents. This makes sailing a lot more predictable than it used to be.

[mabbo]

I wonder how navigation changes if your ship has a set of these.

You've got one movement source - sails - whose power is based on the relative wind speed and direction and has near-zero variable cost. You have a second movement source - your engine - with fewer limitations but a higher variable cost (fuel cost + CO2 emission costs). You have a whole ocean with at least a week of predicted wind speeds and directions.

You've got a schedule to keep, but maybe not one that requires you to be there as quick as possible- after all, ships are slow-steaming now, right?

All together, a straight line often won't be the most economical route anymore. Tacking a little bit to get better wind could make the investment in these sails pay off faster.

[jmoorebeek]

I totally agree that route optimization takes on a whole different dimension now! For our early models and numbers, we're just benchmarking no change in route of speed, to really highlight the baseline benefits of sails. However, there are tremendous knock-on effects that would give you an advantage to follow the wind. We can make use of not only improved forecasting, but better satellite weather data and connectivity to ships to provide updates in real time. Altogether, there will be a lot of performance on the table that ships can take advantage of in the future.

[usrusr]

My favorite green energy miracle fantasy these days it's wind-powered autonomous ships, cruising cross-wind wherever the weather is best suited, going nowhere as far as they can. With an appropriately sized underwater fan driving a generator which drives a hydrolyzer, and when the hydrogen storage that fills the bulk of its hull is approaching maximum capacity it sets home to the homeport (or wherever prices are favorable for selling the harvest and buying maintenance?). That would solve both mooring and transmission for true offshore wind harvesting, and if someone found a way to build that thing cheap enough for making a profit from the hydrogen, that miracle of market economy which so often causes tragic outcomes would cause more to be built until whatever demand for hydrogen we might create is saturated.

(Buy I'd expect the winning designs to be kite-based, and according to jmoorebeek's dismissals of kites for transport they should do well for this use case of mostly stationary criss-crossing. Hulls could be of the semi-submersible type, for stability, where only a narrow tower for sensors/comms/sails protrudes to the surface, because no cranes would be involved in operation)

[julosflb]

Did you check https://farwind-energy.com/fr/ ? That's exactly what they are trying to do !

I would really like to see numbers; as elegant as it appears, I don't really think it can be very efficient.

[jandrese]

This is super cool. I hope it pans out this time. I've seen a number of attempts to add sails to cargo ships in the past, and generally they have not been a success because it involves adding a skilled person to the crew to manage the sails and cargo companies are allergic to paying extra salaries, even if they manage to make more than their salary back in fuel costs.

[jmoorebeek]

This is definitely a place where we think we can leverage modern automation processes. No need to add additional crew to manage the rigging, and the system should be able to manage itself safely.

[tdy721]

This is neat, but I wonder about applying thrust through the container?

I also was kind of expecting a kite TBH. I wonder if the extra work of a kite is a good trade off, I feel like the tying off the thrust issue is easier with a kite than a mast.

Edit: I see wingsail in the title and I think it’s slightly ambiguous. I want to say this is “mast” based? Not a tech issue but

[jmoorebeek]

From our first analysis, applying the thrust through the container seems doable; the containers are secured to each-other and the ship via mechanical "twistlocks", which are designed to handle not just ship loads, but also trucking loads (such as a 2g hard braking from a semi). The roll loads are actually the more difficult design challenge.

Regarding kites, we looked at those quite a bit. The challenge with those is that kites tend to be best for when the wind is coming from behind you or crosswind. For a container ship traveling at high speed, the kites would act more as a parachute and slow you down (even if you were extracting energy from them).

[usrusr]

Yeah, I'd say that kites would be far more practical considering that automatic piloting should be easily solved (trivial compared to e.g. driving cars or landing rockets) and structural changes to the ship would be so much smaller.

But https://skysails.com have completely given up on ships (full focus on stationary electricity generation), and they had already been at the point of operating an installation on a real life freighter. But at least it's not clear that their goodbye to ships was due to technological challenges: it might be because of unrelated business events, e.g. the shipping company they partnered with was already on the course to failure (chances are from their perspective the kite project has been a desperate hail mary from the start), and are some point the not-electricity part had mostly pivoted to shopping management software and that part was eventually completely separated from anything kite related.

[bufferoverflow]

Kite systems for cargo ships already exist

https://www.airseas.com/seawing

And they seem to make more sense than sails.

[yesbabyyes]

Neat! I love seeing this type of technology, offloading/optimizing using a fairly simple idea; though I doubt it's realization was easy!

Nitpick: you seem to have a typo under "Safe": it says "safely and secularly" which I'm fairly sure should be "securely".

Godspeed!

[bksdacosta]

Hahaha, thank you - just fixed! Our website was drafted up quickly to show off our marketing video - can you tell?!

[Maakuth]

Norsepower (https://www.norsepower.com/) is a Finnish competitor that already has run some pilots and there are ships being built with their technology. I hope the competition helps both thrive!

[heleninboodler]

Lots of questions about whether the container tie-downs can withstand that type of load, and apparently they can, but I'm curious what you'll do about the fact that you're relying on 3rd party containers underneath you being in spec. Do you have a mitigation plan for damaged container connections below you in the stack? This seems like a variable that could be outside your control.

[ArpanRau]

Containers being out of ISO 668 and weak was a risk that worried me for some time, but it turns out this is a risk for existing owner-operators too! Containers are inspected pretty regularly to make sure they're OK, or so our customers keep assuring me.

With that said, I'd really like to have some sort of load path-sensing autonomy onboard, like strain gauges in the corner posts of our sail which detect an incorrectly fastened or out-of-spec container before the other corners fail. Should be pretty detectably nonlinear if one twistlock isn't installed right and one corner post isn't transmitting any load.

[sugarkjube]

I seem to remember this was being tried already a while ago.

https://www.wired.com/2008/01/kite-powered-fr/

I don't know about the outcome of that particular experiment, maybe you do ?

What competetion do you have at the moment and where do you differ ?

Anyways, I hope this takes off and we hear more from it.

[atlasunshrugged]

Questions for the maritime folks in the group: What would it take to re-start the shipbuilding industry in the U.S.? In a world of potentially more contested waters, is there a need for smaller more nimble cargo ships or will the unit economics of large ones always outcompete them? Any innovations you're surprised don't exist in the industry yet?

Yes, I am fishing for ideas!

[ianburrell]

My feeling is that would need to get rid of the Jones Act. The protection of shipbuilding and shipping industry have captured both of them and turned them into shadows. Without protection, they would have to compete. They might be destroyed or might survive, but better than limbo.

For example, there is market for shipping containers along the West Coast. Most of the inter-US shipping goes by rail but sea would make sense for some of it. Small container ships would be perfect and locally built would make sense.

[bfrink]

A large Great Lakes cargo vessel was recently completed by Fincantieri Bay Shipbuilding (https://en.wikipedia.org/wiki/MV_Mark_W._Barker). Great Lakes vessels need to be built in the US due to the Jones Act, but they also tend to last a very long time in the fresh water in which they operate, so this is the first lake freighter built in many decades.

Ships for the US Navy (including the Military Sealift Command) are also built in the US. So, shipbuilding hasn't stopped, but the US's comparative advantage is not really in shipbuilding.

[josh_carterPDX]

The ship building industry is alive and well here in the PNW. I think the biggest threat is the work force. Many people are retiring and we're not doing enough to back fill what we're losing. Add that the Jones Act keeps international companies from being part of the process and we're going to run into a wall very soon.

Innovation is coming, but the labor unions are apprehensive. We have literally heard them say that they don't fear automation and innovation, but "put a steering wheel on it." That's such a short sided perspective and if it doesn't change soon, we're going to see a very crippled industry being outsourced by international companies.

[tablatom]

Probably not the idea you were fishing for but

https://www.realclearscience.com/quick_and_clear_science/201...

[macmac]

A practical collapsible container still has not been made. If you could stack 3 collapsed containers in one slot, that could be a game changer for repositioning.

[blitzo]

I like wingsail. I learnt a lot about it when i do some digging about catamaran few years back. There's some of them equipped with combination of wingsail and solar-battery which is neat. Really hope it becomes big in shipping industry. Have smooth journey you guys!

[ck2]

This is awesome because everyone needs to read about how cargo and cruise ships burn disgusting, super nasty "bunker fuel" and make the world even more toxic.

https://en.wikipedia.org/wiki/Fuel_oil#Health_impacts

https://www.cruiselawnews.com/2010/05/articles/pollution/rea...

[Gwypaas]

New rules more stringent rules have been in effect since 2020. Now the limit is 0.5% sulfur globally, with harder restrictions in many places around North America and Europe.

https://www.imo.org/en/MediaCentre/PressBriefings/pages/03-1...

[engineer_22]

The promo video claims a 60m Mirage sail can provide 400kW of power.

Accounting for weather, berthing, and efficiency, let's assume the sail can provide that power for 4 hours of every 24 hour period - that's 1,460 hours/year .

Each Mirage sail might therefore provide 584,000 kWh per year of useable power.

A gallon of bunker fuel is worth 11.0 kWh/kg [1]

So, a Mirage sail can compensate 53,090 kg of bunker fuel per year.

Bunker fuel is priced around $600 USD / metric ton. [2]

Therefore - the expected value of each Mirage sail may approach $31,850 per year. Assume a 10 year service life. Each Mirage must have an installed cost of $318,500.

If you triple the assumption of 4 hrs/day to 12 hrs/day efficiency, the value scales linearly to $955,500.

[1] http://www.cmar.hk/contoil_flow_rate.pdf [2] https://shipandbunker.com/prices

-------

Edit: Outsail's website lists the fuel offest to be 2,000 metric tons per year. Let's assume fuel is converted at 50% efficiency, we can say that they're looking for the sail to return 11,000,000 kWh per year. That's 27,500 hours of sailing per year. There are only 8,760 hours per year... oops.

-------

Perhaps, let's look at it another way.

24 hours x 400 kW x 365 = 3,504,000 kWh

2,000 ton x 1,000 kg/t = 2,000,000 kg

3,504,000 kWh / 2,000,000 kg = 1.752 kWh/kg assumed fuel value

Oops again...

[bksdacosta]

We couldn't fully explain that 400kW number in the video, but our video says "average power" and it was based on a standard transpacific route. The 400kW already takes into account the times the Mirage is not being used, both for bad weather and time at port. Depending on the wind speed and direction we can provide a lot more than 400kW. Using 24 hrs/day we get an maximum install cost of 1.9 million!

[rjmunro]

The idea of having 2 tape measures extend and somehow zip together to form a strong structure reminded me of this thing: https://www.youtube.com/watch?v=AukVObyIF90

Something like it might make a good centre core to reinforce your sails.

[josh_carterPDX]

As someone who runs an accelerator focused on the maritime industry (maritimeblue.org) this is awesome! I've seen some of this technology being tried in the nordic countries and it's nice to see it being built here in the US.

If I can be of help, please let me know. My email is [e-mail].

[brianbreslin]

This is neat, have lots of questions about how sturdy the connections are between TEUs. Also How difficult is it for the captains and crew to pilot a ship like this? How much cargo capacity has to be forsaken for these to be installed? 20 TEUs?

This feels like something that the govt should be subsidizing through grants.

[mkehrt]

This seems extremely cool. Howeever, I'm not sure I believe the attachment to the container beneath the sail is structurally sound enough to hold the wing, especially with wind blowing. Do you know that this will work? (I'm just curious; I know very little about shipping containers.)

[King-Aaron]

> imagine a tape measure. In a tape measure a thin, flexible strip of metal is wound into a spiral

What kind of failure modes are you factoring for when a giant high tensile spring might fail/ lose containment? There is an enormous amount of energy being stored in this concept?

[musesum]

My old boss invested in Kiteship. The Oracle Americas Cup team deployed one for a day -- but, not during competition. I suspect it messed with the competition's head for a brief moment. He did mention container ships. Feel free to reach out and I'll introduce.

[candyman]

I have been learning more about this industry and the need for efficiency since I had to do research for an article on Heidmar (https://www.spacvest.com/heidmar-shipping) since a part of what they do is help shippers understand and optimize their projected energy consumptions. I guess it will also spur an upgrade of the fleet to more efficient units. Installing units like these could be one of the value added services they might get into. I'd like to see more figures and backup on the website about the cost and potential savings. It's hard to get people to do something new unless the economics are very compelling.

[changoplatanero]

did you put your prototype on a small boat and test it out in the water?

[jmoorebeek]

Not yet. Our first prototype is a bench model without the necessary structure to handle full loads. We're working on the detailed design to get on the water now.

[girthbrooks]

Really interesting concept, will follow your success on LI, very excited to see this grow.

I think innovative solutions like these for pre-existing industries are fantastic. Really stoked someone is focused on this topic, even though 5 minutes ago I was uninformed.

[nickff]

There have been, and continue to be many companies focused on harnessing wind power for reducing cargo ship emissions. OutSail's (proposed) innovation is putting the sail into a standard inter-modal container form-factor.

[wisaacj]

This is an awesome idea! Whilst I know nothing about containers, I find myself wondering if the connections between containers would be able to support the massive moments of force from these sails. Also, would you have to ensure that all the wings are based at the same height on deck for stability or can that be effectively managed through extending and contracting individual wings? Finally, suppose you need the sail containers to be as close to the deck as possible (anticipating one response to my previous thoughts), how much shipping volume would be sacrificed by being unable to place any containers directly above?

[gkanai]

Please get a mic for any/all future videos. The mic on the camera is way too far away from your mouth for us to hear what you are saying clearly. Audio is more important than video content in a promotional video.

[hooverd]

How are the Mirage containers powered and controlled? You have a very interesting product and I wish y'all the best of luck!

Also, there's something about the animations in your demo video that reminds me of a Dahir Insaat video.

[bksdacosta]

The Mirage will be controlled autonomously and the Captain will have an override panel in the bridge. It will be powered with batteries, which will be recharged with solar panels or a wind turbine.

Also, hahaha, just looked up Dahir Insaat, thank you I guess?!

[theflyingpigeon]

Not sure if anyone asked this question here but how do you plan to transfer the load of the wings/sails to the structure of the vessel?

A medium containership that weighs 150 tons moving at 20 kts has a lot of energy. If the wing is providing 10% of the propelling force, it’s like pushing/pulling 15 tons.

You need to transfer that to the structure of the ship, which may not be built to support that kind of stress.

Edit: I’m a software engineer at a maang company but my background is in maritime - I went to maritime college.

[jrpt]

If the relative wind is mostly coming at you from the direction you're traveling, then the component of the relative wind in the direction of the ship is negative. So I'm having trouble figuring out how this actually works to convert that into a force going in the ship's direction. Do you have a quick primer for how the physics of it works? Like a small explainer of this claim: "standard sails can still produce forward thrust as long as the wind is at least 20 degrees off from directly in front of the vessel"

[Schroedingersat]

It's the same way racing yachts can move significantly faster than the wind.

Think of it from the boats point of view. If the wind has a mass of 1 unit and is moving at 1unit/s 20 degrees from headwind in the boat's frame, then it has an x component of 0.34 units/s and a y component of 0.93 units/s. Redirecting it purely in the y direction moves it at 1 unit/s giving a momentum to the boat of 0.07 units. The 0.34 units in the x direction gets resisted by the water.

The theoretical perfect boat with perfect sails and no slip and no drag will always accelerate in its own frame as long as there is some cross wind (at an ever decreasing rate) as it is always accelerating air backwards by removing the x component and keeping energy constant.

[MagicMoonlight]

Or you could just build a nuclear powered cargo ship. No refuelling, no pollution, constant power.

The one form of transport where a nuclear engine is both viable and already proven. Why are you messing about with sails?

[nradov]

Nuclear powered cargo ships are generally not viable outside of a few niche roles. Trained operators are too expensive and in limited supply. Many nations won't allow such vessels into port due to concerns over security and accidents. There is an obvious risk of terrorist attacks to steal nuclear material or just cause a radiological incident. And several large merchant ships sink every year; no one wants a sunken reactor contaminating their coastal waters.

Even navies make very little use of nuclear power. It is mostly only for aircraft carriers and submarines. Experiments with nuclear powered surface combatants were mostly failures.

A more viable approach would be to locate the nuclear reactors on land where they can be operated more safely and economically. Then use the generated heat and power to manufacture carbon neutral synthetic fuels to power ships.

[pstuart]

I'm guessing the economics of nuclear are not as good as wind.

[felixg3]

https://en.wikipedia.org/wiki/Otto_Hahn_(ship)

[swyx]

i mean what are you going to do with the 55,000 existing cargo ships out there? throw them all out to build your 500 nuclear ones? this is a legacy business

[ramesh31]

This seems like a really good idea on the face of it, yet sails have obviously been around since the first cargo ships were built. What are the drawbacks and why is this not more common already?

[titannet]

Most sail concepts don't work with today's open deck cargo ships, that problem is solved by the OutSail concept.. but it still faces many more problems: - Is the connection enough to transmit the sail forces? - How will a ship with no sailing keel behave? - How will it affect balance and righting moment? - How will it behave after years of poor maintenance? - What happens if the wind picks up and the sails are not retracted early enough? ( The wind forces acting on a sail will at some point prevent you from hauling it in, but with traditional sails an axe can solve the problem )

[BWStearns]

This seems really awesome. Just out of curiosity, why not take advantage of the stacking nature of containers to make the wing sheath 1xN? It seems like having a deeper sheath you could get more flexibility in wing construction just by virtue of more room. Also, to echo @roter: how does the stack below the sail container handle the extra force from the sail? Are there extra stays from the bottom of the sail container to the deck/gunwales to keep it from toppling the stack?

[jmoorebeek]

I like the deeper sheath idea, but we moved away from that early on for a few reasons. A major one is cargo-handling, because you rapidly hit limits on how high the cranes can lift containers away from the deck. They can't start moving sideways until the entire container is free and clear, and if your container is too tall you may not even clear the stack before the crane reaches its upper limit. From a load management perspective, if you have the choice to go taller or wider, it's generally better to go wider. This also plays into the idea of using tape-spring rollers to store the sail material - it lends itself to being wider, rather than narrower. You can look in a few of our other comments below for more of a description, but yes, we plan to have load spreaders to reduce the compression load on any one stack, and tethers deployed to the main deck to provide additional tension restraints.

[keizo]

Really cool to see this.

Has anyone done any quick models/math on foil assisted container ships? I have no opinions, someone mentioned it and it got me wondering how the math fairs.

[octo123]

Few things, Maybe get some actual riggers or yacht builders as consultants.

Who do you plan to sell to ? Foreign flagged vessels ? Foreign ports? This will have a big impact on the crew running the ship.

Who is going to run maintenance on your sail/ device ? Do you expect the ships engineers to be trained on your systems and run routine maintenance?

Finally, I think you need to learn a tremendous amount about stevedores and expectations on your container being placed in the correct place everytime.

[alfor]

How the two parts of sheet metal are joined together? How are the reinforced inside?

Make me think of a design like a zipper, but I don’t know at that scale what would work, magnets?

Maybe there is a way to transfer the loads to more than two container without making it too complicated. Anyway you can always start to operate in the best wind conditions and scale up from there.

Love the idea, the simplicity and integration with the current system is genius! Wish you great success.

[Nifty3929]

Relevant Context: Shipping contributes about 3% of anthropogenic carbon emissions:

https://www.imo.org/en/OurWork/Environment/Pages/Fourth-IMO-...

"The share of shipping emissions in global anthropogenic emissions has increased from 2.76% in 2012 to 2.89% in 2018."

[DMell]

Does this have any impact on the stability of the ship in rolling seas? Is this an issue that is countered with ballasts or would there need to be thought into a more traditional sailing keel?

Also, what is the maintenance like on these? When I was in the Navy we had huge crews to conduct routine maintenance but on cargo ships, there tend to be small numbers.

Love this - what a cool idea!

[jmoorebeek]

From our early investigations, many cargo ships already maintain sufficient moveable ballast (ie: water tanks) in order to handle dock operations, that they can also handle the roll moment from the sails. Maintenance is on our mind too. The possibility with a containerized solution is as easy as "ship it back to the manufacturer by putting a shipping label on it" for maintenance, and we can make sure to have spares dockside for our customers while their main device is being serviced.

[seu]

There are projects out there to build or retrofit cargo ships with sails, have you looked at them, and what makes you different?

e.g.https://www.dykstra-na.nl/designs/wasp-ecoliner/

[Daniel_92]

Where does this go onboard? Is the thought that this could be the last loaded container, or would these be mounted directly onboard somewhere? Seems like measuring wind at the device instead of at the helm would be better. Interested in where this goes, congrats on the launch.

[jack_riminton]

Awesome idea. Would the potential savings in fuel not warrant this as part of a more permanent fixture onboard rather than from shipping containers?

(Assuming a fuel price of $550 per metric ton, the cost of fuel for a trip from China to USA would be around $1,485,000 (2,700 metric tons * $550))

[jmoorebeek]

We agree that a permanent installation would be awesome, but we came across some difficulties with that idea in customer conversations. First is the number of containers you permanently displace might mean you never recover your investment. Having a removable solution allows you to access the containers under the sail without any difficulty at the port. A permanent solution also requires time in a shipyard to install the foundations and mechanisms. There are thousands of ships out there which will need retrofits, and shipyards are already struggling with capacity, so a solution which you can build inland, then ship to and rapidly install at a dock makes sense to us.

[stall84]

As a pilot, I would like to recommend to ANYone interested in anything involving air as a fluid, the absolutely amazingly written (the man has absolutely beautiful analogies at every paragraph of the book) 'Stick and Rudder' by Wolfgang Langewiesche

just my 3.5 (inflated) cents

[dokem]

I have a better idea. Bring some manufacturing back to the US. Container ships are already 2x as efficient as trains. You're going to get a lot of green-blinded yes-men in here so I'll chime in to say I don't believe in this. Really, something with the footprint of a container is going to move a container ship? This is a joke. Are we supposed to be dazzled that you worked on satellites? I worked on satellites - that doesn't mean you automatically know about everything especially after 10 years of experience. The maritime industry isn't filled with a bunch of idiots that don't care about efficiency and haven't heard of a sail boat before. If it was practical they would have sails already. We have sail boats. It's already a thing. They're not on 1000+ ton vessles for a reason. You are wasting your time and money. I'm only trying to help.

[julosflb]

Although I don't necessarily share your tone, I share some of your ideas.

https://www.lowtechmagazine.com/2021/05/how-to-design-a-sail... is worth reading. Basically container ships are incredibly energy efficient. If we want to go back to sailing ships for cargo, then we need to massively scale down global exchanges.

Now on a positive note, if we find some devices, easy to operate, low cost and that can save few percent of fuel (being fossile or green), then that could still be useful.

[cjlars]

Why is a retracting mast preferable to a freestanding rig with, e.g. a roller furling main or a nonsuch style wishbone boom? Is there a physics reason or is this a pragmatic trade-off to fit under bridges and stay out of the way during loading?

[wongarsu]

Typically attempts to fit sails on moderns ships (like the rotor sails that have been installed on some ships in recent years) are targeted at ferries or tankers, exactly because of the loading/unloading topic. Putting large structures on a container ship will interfere with the cranes. And the SC Connector launched in 2021 can tilt the rotor to fit under bridges, with sails half as high as what OutSail tries to do [1]

1: https://www.rivieramm.com/news-content-hub/sea-cargo-ro-ro-w...

[ArpanRau]

Retraction is pragmatic: Air draft and loading/unloading concerns. Wings because they perform much better than traditional sails when installed on ships that are already powering forward at speed.

[Cthulhu_]

While the idea of a sail module in a container sounds really smart, won't the sail need more anchoring than the underlying containers can provide? That is, shouldn't it be bolted down to the ship itself?

[sails]

Definitely very excited by this, sails, boats, trade winds, hardware. Cool project!

[latchkey]

https://www.fastcompany.com/90850262/why-cargo-ships-are-bri...

[logicallee]

since the oceans are mostly empty and in international waters, i.e. lots of available area, why don't ships pull enormous solar arrays behind them for energy?

[cedricd]

Only a guess, but drag would probably be a concern and could very likely undo the effects of the solar arrays.

[WalterBright]

> The idea for OutSail came from

Proposals for adding sails to cargo ships goes back decades. While I wish you guys success, it's going to be tough sailing.

[dpflan]

Do you have a full-size working prototype? Have you tried this on a real shipping container ship? And can't Maersk just copy this concept?

[jmoorebeek]

Our current prototype is a 1/50 bench model using off-the-shelf tape measures. We're working on rapidly scaling that up to test on our Lido-14. I'm sure others will try to copy the concept, but as the comments have shown there will be quite a few engineering difficulties getting this from a bench prototype to production. As a startup rather than a legacy company, we are well situated to take on that difficult engineering task, whereas a larger company may shy away from it. We'd of course be happy to work with them to get this on a ship and de-risk the rest of the operations!

[gautamcgoel]

I have a simple question: how did you make the video on your webpage? Did you contract with an outside firm? Also, who made the music?

[supermatt]

A traditional mast isn't just standing on the deck. Won't this style of mounting just rip the container from the ship?

[twic]

Can existing cranes lift double-width containers?

[bksdacosta]

Cranes can lift double wides, the bigger limitation is the maximum weight a crane can carry. Luckily, a Panama sized crane can lift 40 – 50 tons and our current weight estimate is fairly below that.

[skanga]

Great idea! The world needs this - if it works.

Just like some strong pressure will bend a tape measure - will a strong wind gust damage your sails?

[jmoorebeek]

Of course, there will be limits on the wind speed the structure can handle. Flexing of the structure will be designed in, similar to how a 787 wing flexes by design under load. For stronger gusts, aside from design margin, we are also looking at technologies that can help us see gusts coming, for instance LIDAR systems which are already used on ships which can detect windspeeds for kilometers around the vessel. We can then reef or feather the sails when we see a gust coming and remain within structural limits.

[spiritplumber]

Hi, we made an autonomous sailboat in 2008 and have been making autonomous boats ever since. Want to collab?

[jmoorebeek]

Feel free to contact us via our website, we'd certainly be interested to chat!

[quirkot]

questions:

1) what size container ship are you targeting?

2) how many container sails are needed in an array to achieve 20% fuel cost reduction?

3) what scale of retrofitting is required to install this onto existing fleets?

4) what sort of training is required for existing staff to properly trim the sails / will this impact headcount requirements per ship?

[bksdacosta]

1.We are talking to ship owners with Panamax vessels (3000 – 4500 TEU). Therefore, many of our estimates are based on a vessel of that size. Nevertheless, our product will work with any sized container ship.

2.We will need 15 sails to save 20% fuel on a 4000 TEU vessel travelling transpacific or transatlantic.

3.We will install an override panel on the bridge of the ship, a lidar system to sense wind gusts and some extra lashings will be tied from the sail’s container to the containers below it – that’s it! None of those additions will require permanent changes to the ship.

4.No extra staff will be needed, our sails will be controlled autonomously. However, the captain will be given controls in the bridge if they ever want to force the sails to retract.

[1970-01-01]

You should be advertising on your wings. That's too much space to leave blank. Good luck!

[carabiner]

Yeah for a sec I wasn't sure those were the actual product. I thought those were support pylons that would connect the sails, turns out those are the sails. I'm guessing they're just like high aspect ratio wings, long and skinny to minimize drags.

[davewood]

why do we need to plaster every available surface with ads when their purpose is mostly to increase consum even more?

[davidw]

You probably need to commission a sea shanty to sell this product.

Joking aside, it looks interesting and cool.

[swyx]

OP, unironically, please do this, as someone who works in marketing this will be a hit

[oriettaxx]

Do you guys have yourself any sail experience? winds strength is amazing (and scary)

[KyeRussell]

This looks cool! One thing I don’t get though. How are you using GPT-3?

[andy_ppp]

Cool demo, but I think containers are not bolted down and they regularly fall off the side of the boat. Obviously these will have quite a lot of force going through them to be able to move a ship to any degree, so what is the plan to be able to bolt them down? How will they cope in weather like this? https://youtu.be/diOdeVaAfDU Of course you'll say the crew will remember to pull the sail down in time every time they come into bad weather but I think you'd be surprised how quickly things can change at sea (generally satellite info is not granular enough to predict/catch everything). Maybe some automatic weather detection is needed.

I think the idea might be more difficult to implement in reality but would love to be proven wrong. I wish you more than luck.

[theoa]

So what's the timeline for launching the Kickstarter campaign?

;-)

[revscat]

How are they powered?

[Rorando]

I would assume the same way reefer containers are, hooked up to the ships onboard power distribution. Electrically rigged sail of this magnitude does not impose any significant loads on the grid onboard

[anonymous344]

how is this better than the computer guided kite?

[bksdacosta]

Kites are incredible for sailing downwind; however, they don’t produce sufficient thrust when sailing upwind. The vast majority of container ships travel faster than 15 knots causing most of the wind they experience to be upwind.

[WalterBright]

> use a vessel’s Carbon Intensity Indicator (CII) to grade ships

Oh criminy. We have fuel economy regulations, carbon offsets, carbon footprint mandates, ICE regulations, natural gas bans, all sorts of daft proposals to avoid doing the simple, obvious, easy, efficient, and effective obvious:

Tax the carbon atoms in the fuels.

[go_elmo]

A general shift in mentality and therefore law has started and needs to be pushed through in the next years:

Price externalized costs.

The world was treates like an infinite resource that it isnt. Emit carbon? It has its price to emit that that someone needs to pay. Same should go with noise etc. Reving that Car at midnight waking up hundrets of people? That does an economic health damage of thousands of dollars too.

[somewhereoutth]

Taxation may help in reducing the attractiveness of carbon fuels, but essentially we need to stop carbon atoms getting into the atmosphere (as CO2). It doesn't matter how much tax is collected, there is not (currently) much that can be done about the CO2 released.

Simplest solution is to leave it in the ground. Just reduce the amount of oil/coal/gas dug up and burnt - we (or the corporations) know exactly how much is being dug up, so stop the digging.

[Stevvo]

Masts have rigging for a reason. You can't just fold one up in a box; the physics doesn't work, mast will be torn off by the first big gust.

[wffurr]

There are many designs of unstayed masts throughout history including modern designs with aluminum and carbon fiber: https://www.google.com/?q=unstayed+mast&tbm=isch

America’s Cup AC55 yachts come to mind with an unstayed carbon fiber wing. As do friendship sloop two masters.

[Rorando]

Sails can be deployed without conventional rigging. I have experience of these so called free standing rigs myself. Dynaspar rigs is one real life example.

[acyou]

What technology do we have access to now, that wasn't available at the close of the Age of Sail and the dawn of the Age of Steam, that will make us succeed where others have failed?

Obviously, slapping a sail on a diesel powered ship straight up doesn't work. We would have done it. We need something more.

WE have microprocessors, textiles, steels, servo motors, FEA. We are up against the tyranny of 200 years of incremental efficiency gains, fluid mechanics, and essentially thermodynamics.

Not that excited about the shipping container or even the sail. That is an arbitrary gut feel design constraint that may have gotten you into YC, but we can feel free to toss all of it by the wayside now that we are getting serious, no?

Engineers need a good gut feel for torque, impact, and dynamics, and the big picture. We have to think about more than just static forces and how to make our pet square peg ideas fit into real world corkscrew holes.

We should try to make a servo operated kite that pulls straight upwards and sometimes forwards or a little sideways, (much more than it pulls backwards), that we put on a very slow ship, in very windy conditions.

Why do all of this work? We should just develop some sort of golf ball coating or fairing and coat or cover the tops and sides of some containers and do some wind tunnel studies, patent it and sell it for $$$, and call it a day. It might even be an actual efficiency improvement.

[stevage]

>Obviously, slapping a sail on a diesel powered ship straight up doesn't work. They would have done it. You need something more.

Who is they? The early days of steamships indeed had both sails and engines on the same ship.

Mostly shipmakers haven't put sails on oil-powered cargo ships because there hasn't been a strong need for it. Fuel isn't expensive enough to warrant the extra effort. But the desire to reduce CO2 emissions starts to tip the scales.

[tired_and_awake]

Its about the market, not just technology. There is appetite to reduce emissions now that didn't exist even 10 years ago.

If they can reduce fuel consumption 20%, maybe it's not a unicorn but it'll (hopefully) make some money. Also it gets creative people with novel motivations some real experience in the space, maybe they learn something and maybe they iterate.