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A new design ship in the Philippines is partly powered by wave energy

bbc.com

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Re: A new design ship in the Philippines is partly powered by wave energy

#91

Post by wenc »

just-ok wrote: post #11
genocidicbunny wrote: post #9

Earlier quoted context omitted.

I can't imagine there would be that many. Sails just don't provide all that much motive force, and they're far too unreliable (wind dies down, it doesn't matter how much sail you have.) Maybe the GP was thinking more along the lines of general 'green' tech -- wind turbines, solar panels, etc? It would certainly be cool to see more of those to supplement existing propulsion systems on ships, and that would help reduce…

Combining technologies would absolutely be a great way to pivot, as the article shows. Maybe it’s a dumb question, but why don’t we have sails on modern ships as a supplement? I just lament that we basically completely abandoned such a great mechanism (sails) so haphazardly just because coal was cheap & reliable; now the environment pays the price.

We do. They just don't look like sails. This is a Maersk ship.

https://en.wikipedia.org/wiki/Rotor_ship#/media/File:Norsepo...

Re: A new design ship in the Philippines is partly powered by wave energy

#92

Post by MaxBarraclough »

reportgunner wrote: post #50
messo wrote: post #22

> The emissions from travel it took to report this story were 0kg CO2. The digital emissions from this story are an estimated 1.2g to 3.6g CO2 per page view. Maybe this is what finally could push companies towards making lighter and more efficient websites? At least an estimate of a webpages watt usage (server and client side).

I was also disappointed with the amount of text compared to the amount of information in the article. It seemed like every paragraph started with for sure you have been in the waves so you know they are waves

Agreed, far too much waffle. The first three paragraphs don't even mention the new ship design.

Re: A new design ship in the Philippines is partly powered by wave energy

#93

Post by sephamorr »

maelito wrote: post #55
sephamorr wrote: post #53

Earlier quoted context omitted.

I'd probably use closer to 10W as the device power level (a standard laptop, what I'm using right now), so the number for me would get close to 0.2g, but your point stands; the article is answering a different question than I was assuming, but regardless it seems that the majority of the energy is clearly the local device.

Isn't a modern laptop mostly idle after loading the page ( There would be a peak for the first seconds, then less than 10W for the rest of the reading time ?

Definitely the peak would be higher. My laptop has a ~60Wh battery and gets ~6hours of battery life, so I was just assuming 10W average for web browsing.

Re: A new design ship in the Philippines is partly powered by wave energy

#94

Post by 0xffff2 »

chriswarbo wrote: post #69
proto-n wrote: post #66

Earlier quoted context omitted.

Also why not add sustinance cost for the human looking at the device then? Food, water, heating/cooling, clothes, glasses, etc... Proportionally for 2 minutes of course.

Those costs would be the same if the article was read from a newspaper or magazine, so they can be factored out.

My desktop is on whether I'm reading the article or not so those costs can be factored out too.

Re: A new design ship in the Philippines is partly powered by wave energy

#95

Post by michael1999 »

Xylakant wrote: post #33
bigbluedots wrote: post #29

Aren't all ships partly powered by wave energy if they're facing the right way?

No, generally speaking, waves pass underneath a floating object in practically all circumstances. You may feel like there’s a forward surge when a wave comes in from behind, but all forward momentum gained while sliding down the wave is lost once the wave peak has overtaken you and you’re climbing back up the wave. Basically, waves will induce a circular motion on a floating object. There’s ways to trick and gain for…

Nice explanation.

A boat can start surfing once the waterline fits on one face of a wave, so https://www.passagemaker.com/lifestyle/freaks-of-nature-rogu...

The wave-glider is much more practical.

https://www.liquid-robotics.com/wave-glider/how-it-works/

Re: A new design ship in the Philippines is partly powered by wave energy

#96

Post by rstuart4133 »

sosborn wrote: post #6
just-ok wrote: post #5

It’s honestly a shame that we didn’t keep pursuing sail technology. It’s great that we’re finally getting somewhere environmentally-friendly with ship tech nowadays as in the OP, but if we’d put the same amount of effort to innovate and advance sails like we did steam, I imagine we’d have pretty amazing (and completely green) methods of transport for all but the heaviest cargo loads (and even then, just split the loa…

I’m genuinely curious, what innovations could there possibly be for sails beyond increasing surface area or either the sails or the keel?

As someone who was a racing dingy sailor in his youth, the answer is a gob smacklying lot of improvements have occurred in my lifetime, mostly this century.

Have a look at the America's cup races. Eg: https://www.youtube.com/watch?v=Y325JWyRslE

The first thing that hits you is the hull isn't in the water. The next thing is the sail boats in a modest breeze are giving the powered boats a run for their money speed wise. One thing that is not so obvious is the sails are now more aerofoils.

Back in the day, boats that had no hulls were a mad mans dream. Now we call them kite surfers. Some exotic ones have keel hanging from a bit of rope.

Re: A new design ship in the Philippines is partly powered by wave energy

#97

Post by maelito »

sephamorr wrote: post #93
maelito wrote: post #55

Earlier quoted context omitted.

Isn't a modern laptop mostly idle after loading the page ( There would be a peak for the first seconds, then less than 10W for the rest of the reading time ?

Definitely the peak would be higher. My laptop has a ~60Wh battery and gets ~6hours of battery life, so I was just assuming 10W average for web browsing.

Thanks for the figures. I've bought an ARM PC in part for lowering its footprint.

Re: A new design ship in the Philippines is partly powered by wave energy

#98

Post by wenc »

just-ok wrote: post #11
genocidicbunny wrote: post #9

Earlier quoted context omitted.

I can't imagine there would be that many. Sails just don't provide all that much motive force, and they're far too unreliable (wind dies down, it doesn't matter how much sail you have.) Maybe the GP was thinking more along the lines of general 'green' tech -- wind turbines, solar panels, etc? It would certainly be cool to see more of those to supplement existing propulsion systems on ships, and that would help reduce…

Combining technologies would absolutely be a great way to pivot, as the article shows. Maybe it’s a dumb question, but why don’t we have sails on modern ships as a supplement? I just lament that we basically completely abandoned such a great mechanism (sails) so haphazardly just because coal was cheap & reliable; now the environment pays the price.

I just looked into the economics of rotor sails.

On average, they save $400/day ($146,000/year) in fuel costs (2017) or about ~10% of fuel consumption. In real terms, it's not much.

They cost about €1-2 mil ($1.1-2.3). Under the most ideal circumstances, that is a ~8 year payback, which is fairly long.

In order for the economics to work out, oil prices need to be higher and externalities (CO2 emissions) need to be included in the price.

Re: A new design ship in the Philippines is partly powered by wave energy

#99

Post by handol »

lippel82 wrote: post #78
bildung wrote: post #74

Earlier quoted context omitted.

Found another article with more numbers: "The ship’s “independent multi-engine technology at minimum 3000hp drive shaft sea class” is combined with a wave energy device that’s capable of generating up to 300kw/h of energy, Salvador explains." https://news.mongabay.com/2020/04/a-wave-powered-ferry-aims-...

300kw/h is a nonsensical unit in this case. kw*h would be energy, but kw alone would be the proper unit to compare to the 3000hp drive shaft.

300 kilowatt-hours per hour
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