[ethagknight]

Two problems with boats and solar propulsion: 1) they need 24/7 power. 2) Using a random LG 330 W panel on top of the Edith Maersk, it would take an array 1/3 of a mile by 1/2 of a mile in area to match Edith's 80,000 kW engine power output. Edith is 1/4 mile long and 3/100ths of a mile wide.

Quite a gap, and thats before you start factoring in batteries for the night, structure to support the array, storms...

[Steko]

> 2) Using a random LG 330 W panel on top of the Edith Maersk, it would take an array 1/3 of a mile by 1/2 of a mile in area to match Edith's 80,000 kW engine power output. Edith is 1/4 mile long and 3/100ths of a mile wide.

Back of the envelope math says we're short by a factor of ~108. We can get savings in a few places:

(1) We don't have to match the full engine output with solar. Many container ships use super slow shipping at a fraction of the power, [1] says 10% engine load. With batteries you can still increase throughput substantially when needed.

(2) Panels can exceed current ship dimensions, perhaps greatly (tow a long tail of solar panels on floats?). Let's just go for double width and length for now.

(3) Efficiency gains. We're at 20% in back of envelope above but I can get that for my house. Let's say Maersk ponies up for 30% cells.

Still some ground to make up but at least we're in bullshitting distance of claiming it's viable.

[1] http://articles.maritimepropulsion.com/article/Turbocharger-...

> thats before you start factoring in batteries for the night, structure to support the array

Presumably there's some space/weight savings in not having an 80MW engine.

[flyingfences]

> Panels can exceed current ship dimensions

They really can't, though. Sure, there's plenty of space when the ship is out on the high seas, but any time the ship needs to go into port (kind of the point of a ship) or navigate tight waters such as straits or canals, then the footprint of the panels really has to not exceed the footprint of the ship.

[manquer]

it is not a b/w choice between 100% solar or 100% oil, hybrid solutions could work and address the gaps solar/electric cannot handle,even 10-20% emission savings could mean a lot .

Also it doesn't have to be solar directly, an electric propulsion system which can use hydrogen or high density battery/ storage which plugs into the grid eventually is good enough.

You don't need to drag the cells with the ship, they could be perhaps stationary middle of the ocean and charge the replacement batteries and you could line few such charging stations near the major shipping lines.

[Faaak]

Though you could power the ship from solar during the night and with diesel generators during the night.