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It doesn't carry even a 10th of the cargo of the big windjammers of the 19th century (5000-8000 tons!). Of course, setting aside the value of zero emissions wh
by Quarrel 3y ago
It doesn't carry even a 10th of the cargo of the big windjammers of the 19th century (5000-8000 tons!).
Of course, setting aside the value of zero emissions which is their obvious selling point, it would otherwise be competing against big container ships (up to 200,000 tons!).
I assume that until they scale it for a few more generations that it'll be more a gimmick for low tonnage luxury items that just want the zero emission marketing claim. Even after scaling, I assume it couldn't be competitive for most bulk things.
- Gare 3y agoUse wind power to produce methane, then use methane to power huge container ships. Sailing by proxy.
- hagbard_c 3y agoYou'll be emitting nitrous oxides when burning that methane. Use wind to produce hydrogen, use that in fuel cells. Electric propulsion units are already in use, what remains to be solved is the megawatt-sized fuel cells needed for this application at a price which makes the whole scheme feasible.
- azernik 3y agoHow are you emitting nitrous oxides from a synthetically produced (ie very pure) fuel that contains no nitrogen?
- durundal 3y agoYou’re burning it in air which has lots of nitrogen.
- Gare 3y agoLong term, I agree. But we already have methane and methanol powered huge container ships. Much better than burning bunker fuel.
- hagbard_c 3y agoIt may be the easier option for electrically propelled ships, several of which are already in service. Mind I'm not talking about battery-electric ships but diesel-electric (hybrid, [1]) which have the range and load capacity needed for 'serious' applications. If - and that is a big if - the requisite fuel cells can be developed they could directly drive the existing electric propulsion units in those ships, replacing the diesel generators currently in use. [1] https://www.wartsila.com/marine/products/ship-electrification-solutions https://www.wartsila.com/marine/products/ship-electrificatio...
- toast0 3y agoNOx is addressable through diesel exhaust fluid (urea) and catalysts; maybe not elimination, but at least significant reduction. Methane is easier to store and transport than hydrogen, and there's potential for refitting existing engines to run from cng/lng (although I think purpose built cng powered devices usually start from a gasoline engine design and freight vehicles usually have a diesel engine).
- crote 3y agoHow are you going to store all that hydrogen? You need extremely large and heavy high-pressure tanks, capable of holding 350–700 bar. Methane can be liquefied and stored at only 10 bar. Hydrogen just doesn't have the density required here. Even if you want to use hydrogen-powered fuel cells, it might make more sense to convert it to ammonia for transport and storage.
- fragmede 3y agohow much hydrogen do you need to store though? it doesn't make sense in cars to me, but water-based vehicles seem like they wouldn't need to store problematic amounts given that they have access to h2o
- hagbard_c 3y agoThat would imply the ship has the requisite power generation on board to produce hydrogen from water, in which case it would be more efficient to use that power to propel the ship. So, yes, the ship would have to take all the hydrogen it needs with it.
- fragmede 3y agooh. I thought we were talking about sails to make electricity to run electrolysis to make hydrogen to run engines. storing enough hydrogen for an entire voyage seems prohibitive to me, but I've not done the math
- hagbard_c 3y agoThere's many ways to store hydrogen ranging from 'cryogenic' to 'dissolved in ... (acetone is a good candidate)' to 'converted to ... (ammonia et al)' to 'compressed'. Ships (can) have a lot of space so that is not much of a problem. Cryogenic is probably not feasible, compressed is probably also out but in between there are many options.