Worlds Largest Electric Ship Launched by Tasmanian Boatbuilder
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The launch of the world's largest electric ship has sparked a lively debate about the practicality of installing solar panels on its flat roof. While some commenters, like NooneAtAll3, enthusiastically suggested covering the roof in solar, others, such as victorbjorklund and scraptor, countered that it's more efficient to keep the panels, inverters, and other equipment on land, where installation and maintenance costs are lower. The discussion revealed a consensus that adding solar panels to the ship would introduce unnecessary weight, complexity, and expenses, much like the reasoning behind why electric vehicles rarely come equipped with solar panels. As the conversation unfolded, it became clear that the ship's design is just one aspect of a broader discussion about the most effective ways to harness renewable energy.
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Although at the scale of a one off boat i would think it's cheaper to use the more widespread systems for bigger grid connected panel installations; so you are back to inverters.
And recall that this bridge - https://en.wikipedia.org/wiki/Francis_Scott_Key_Bridge_(Balt... - will need a multi-billion dollar replacement, because the tiny engineering staff of a huge freighter could not diagnose and correct a surprise electrical failure. Within the maybe 3 1/2 minutes between the initial fault, and when the collision became physically inevitable.
I used to work on ships and almost everything constantly breaks down without constant maintenance. I bet it would be much cheaper to put the solar panels on land and charge the ship when it's in port.
The ship battery is 40,000 kwh and uses at least 10,000 kwh per crossing, with 10 minutes to recharge. A handful of kwh are negligible because this isn't a sailboat.
The electricity sector in Uruguay has 98% renewable power
I don’t think you’re listening. This entire argument would lead to there being an expensive solar option for Teslas. There isn’t. It’s a terrible idea because the yield is bad. Solar panels are big flat panels that point at the sun. Cars are made of curved shapes.
I see many Hyundai Ioniq 5s on the roads in London UK. Exactly 0 of them have a solar roof - it's not even offered as an option here. It's a gimmick and there's no demand for it.
Additional weight and complexity on a one off boat would be more expensive than a seperate much more standard solar and battery system on land. And you might be able to get additional value out of selling electricity from an oversized storage.
It's not sensible to draw your system boundaries around the boat by itself; there is significant terminal infrastructure; and even grid electrical infrastructure to consider.
> It's made out of aluminum instead of steel. The resulting weight savings make it a bit more efficient. That's something this shipping yard specializes in.
According to that person, weight does indeed matter.
If you were optimising for mass rather than ease of maintenance you'd probably put them on (despite the relative lack of surface area meaning you still needed to recharge at each end)
This is kinda like saying everyone should wear solar hats to offset their home electric bill.
"In 2020, Buquebus originally commissioned Incat to deliver a new ship to use dual-fuel propulsion, capable of operating on liquefied natural gas and diesel, with around 400 tonne of main engines, 100 tonne gearboxes, 100 tonne cryogenic fuel tanks and 100 tonne fuel."
https://en.wikipedia.org/wiki/China_Zorrilla_(ship)
Same ship, originally specced to carry tens of thousands of liters of oil. No overall displacement number, oddly.
- It's made out of aluminum instead of steel. The resulting weight savings make it a bit more efficient. That's something this shipping yard specializes in.
- Because it is going to run in shallow water on the river Plate, it doesn't actually have propellers but a water jet propulsion system.
Fully charged did a video on the construction of this ship early last year: https://fullycharged.show/episodes/electric-ferry-the-larges...
The project of getting this ship from Tasmania to South America is also going to be interesting as well. It can't do it under its own power; it's designed for a ~50km crossing, not a trans Pacific/Atlantic journey. At the time, they were thinking tug boats.
Apples to orages.
Or to structure it a the earlier comment: for comparison, it takes me about 0.000065 MWh to cycle 1 nautical mile.
That's a couple of apples.
https://en.wikipedia.org/wiki/Maglev
The other is: when will they charge? Does this ship not run at night?
Each trip consumes approximately 1,175 kWh, which is nearly the same amount a residential home consumes in a month. In each port is a tower with a robot arm that connects the charging cable automatically every time the ship comes to the dock. The system charges 10.5 kV, 600Amp and 10.5MW. The batteries have a total capacity of 4,160 kWh, which means that we always have a surplus of electricity if for some reason we cannot load during a stop or if the transit takes more time than usual.
In Helsingör the ferries charge for approx. 6 minutes and in Helsingborg the ferries charge for approx. 9 minutes. This is enough to suffice for the journey across the strait.[1]
Side note: you can also charge your car on board from the boat’s batteries.
[1] https://www.oresundslinjen.com/about-us/sustainability
So ”only” 42 car sized chargers for a massive boat, there are probably some massive Tesla superchargers sites that approach that.
Big difference, since I imagine the turnaround time on a similar ICE ferry would be less than 40 minutes but more than 10.
Another point with battery powered ships is that the rate at which they discharge is speed dependent and that's a non linear relationship because the drag increases quadratic with speed. So, if you are at 30%, you can still make it across. Just not at the full speed. This is less about range anxiety than it is about just being able to stick to schedules. If the ship did not charge enough it would have to go slower. But it would still get there. This ship is designed to go quite fast which means it would have a lot of wiggle room. So they might make it across at full speed even at maybe a 60% charge. The risk is that they'd run low and might have to slow down a bit. It would get there but with a delay if that happens. And then it would have to sit there a bit longer recharging leading to more delays.
The trick is optimizing the amount of batteries to minimize turnover and delays; not around being able to charge them from 0 to 100%. The sweet spot is probably around the 20-80% mark, meaning you'd want to be able do a crossing at full speed using about 50-60% of the battery capacity. The rest is just there as safety margin to avoid delays. If you burn into that, you need to charge a bit more. With 40-50 minutes turnover, there's plenty of time to do that typically.
It's a ship with a very low deck line that partially submerges itself, with the center of the deck underwater deep enough so the other vessel can 'float on' over the deck. They they pump the water back out, raising the deck above water and the boat on top it just rests flat.
They do this for some oil rigs as well.
https://en.wikipedia.org/wiki/Heavy-lift_ship#Semi-submersib...
I assume it’s too hard to be worthwhile, and probably still wouldn’t get the range.
Skips expensive DC charging infrastructure, but does require to buy two batteries which can get expensive. Over time vpp / market arbitrage can pay for battery itself tho.
Also sacrifices some of the cargo capacity. I.e. for wellington - picton that’s about 4 rail cars or 6 semi trailers.
New Zealand should we well suited to electrifying everything, with a lot of good energy sources.
I can’t see the current government supporting anything EV, particularly across the Cook Strait, given the ferry fiasco to date.
New Zealand should we well suited to electric ferries, with a lot of good energy sources.
I can’t see the current government supporting anything EV, particularly across the Cook Strait, given the ferry fiasco to date.
>It's made out of aluminum instead of steel.
<alarm bells going off>
>it is going to run in shallow water on the river Plate
Oh, phew.
The main issue I saw here with the electric ferry was that 90% of the installed generation in the islands uses HFO so we would be charging the ferry with a fuel that pollutes more than the diesel used to run it.
https://www.yachtworld.com/boats-for-sale/length-25/keyword-...
My local ferry system has an electrification project[1]; the current active project is three 160-car hybrid-electric ferries for a total cost of $714.5 million. A NZ shipbuilder is probably more competitive than a US shipbuilder, and details matter....
This article says $200M [2] which is a lot lower than I expected, given it's a one-off and larger (I think) than the WSDOT 160-car ferries.
[1] https://wsdot.wa.gov/construction-planning/major-projects/fe...
[2] https://www.ro.com.uy/2025/10/16/nuevo-barco-china-zorrilla-...
Note that Tasmania is part of Australia. NZ isn't part of Australia yet.
https://www.news.com.au/travel/travel-updates/travel-stories...
If we say it's 7500kWh a month that's something like 250 kWh of production per day, which is a tiny drop in the bucket compared to the amount of energy needed to charge the ferry.
https://www.abc.net.au/news/2025-05-02/incat-launches-worlds...
> ... the batteries will power eight axial-flow water jets driven by permanent magnet electric motors. These will be able to keep the ship going for 90 minutes before needing to be recharged.
> The ship’s permanent home will be the Rio de la Plata estuary, where it will travel between the ports of Buenos Aires, Argentina, and Colonia del Sacramento, Uruguay. The two cities are 60 kilometers apart, a distance Hull 096 is expected to travel in 90 minutes. Direct-current charging stations will be installed at each port and will draw energy from the two countries’ grids. A full charge is expected to take just 40 minutes.
https://spectrum.ieee.org/electric-boat-battery-ship-ferry