Energy for the pumps should be a very small percentage of the energy gains. There is essentially no "head" pressure, just pipe friction losses.
Yes, a very cool concept, and it's nice to know that there are actual pilot plants operating. I enjoy watching Joe's channel.
Distance isn't the only limiting factor... so is voltage. For example to move 200,000 watts 13,000,000 feet (2500 miles) at 2M volts (I think the max voltage used now is a third of that, so not all that far off) only needs 14 gauge wire:...Obviously geography would be the main limiting factor here. I'm 2,500 miles from the ocean. What size wire would I need?
I see fouling here even above the low-tide waterline, so I'm dubious about that.... Recent advancements in UV treatment could potentially solve the biofouling issue?
You might like Tidal Power & the Magnus Effect.... I've been thinking about how to harness the power of the tides coming in/out lately as well.
I think what Schlagger is getting at is that in addition to accounting for the wall-friction Fred mentioned, the density of seawater changes with temperature. Since the colder water is heavier, that requires additional work to "lift".
Salinity changes with depth too. As I recall Joe said it was more effective in the tropics, in which case the salinty is decreasing with depth and would tend to counteract some portion of the density increase from the cold. At least in summer according to the chart.... |
. . . For example to move 200,000 watts 13,000,000 feet (2500 miles) at 2M volts (I think the max voltage used now is a third of that, so not all that far off) only needs 14 gauge wire:
You might like Tidal Power & the Magnus Effect.
The navy report was interesting reading, particularly the rudder applications. Really would like to know how they would do in replacing a keel on a sailboat (obvious drawback is they consume power, but could it be the next America's Cup advantage?).Yes that [magnus effect] was very interesting.
The Alcyone ... daughter of the wind ...
Cousteau was reality TV when I was growing up. Although I don't recall seeing the Alcyone in the TV series much if at all... probably came along after it was canceled or I stopped watching. The sails weren't magnus rotors though [ref]: |
The idea of using a hollow, rotating metal cylinder for propulsion had been tried and discarded decades before Cousteau and a team of engineers decided to revive and improve on it. Cousteau and his associates, Professor Lucien Malavard and Dr. Bertrand Charrier, used a fixed cylinder that looked like a smokestack and functioned like an airplane wing. A movable shutter and system of fan-drawn aspiration improved the efficiency of this new sail. Small-scale models tested in a wind tunnel functioned perfectly, and the Turbosail was born.
But I'm dubious... only the Cousteau society has data on the performance and if it really was so great I feel they would have shared it. Another down side, like the Magnus rotor, you have to burn energy to make it work on some angles of attack.When compared to the thrust coefficient of the best sails ever built (Marconi or square types, i.e. ships of the American Cup or the Japanese wind propulsion system) that of the Turbosail is 3.5 to 4 times superior and gives the system a unique advantage for the economical propulsion of ships.
The invention was first tried on a catamaran christened Moulin à Vent (Windmill). Cousteau and his colleagues validated the system by sailing from Tangier to New York. The crossing was nearly complete when, not far from the American shore, they ran into winds of more than 50 knots. The soldering that held the Turbosail in place gave way and the prototype fell into the sea.
Yes, I wondered the same thing after my last post. So the Alcyone cylinders were not quite as good as a Magnus type. Cool information, nice to see the ship again.Also doesn't have the benefit the magnus effect imparts where it can become transparent to wind
How'd that go?...I remember listing "Oceanography" as my career choice to my guidance counselor!
...I wonder if failure-to-adopt for new ships mostly has to do with cylinders being "ugly" compared to sails. I would take safety and efficiency over aesthetics, but most people find aesthetics pretty important.
Sailing is easy! Only takes a few minutes to learn the basics (a lot longer to master them). If interested and in the U.S. take an ASA or U.S. Sailing intro course. ASA is a little more tailored to those interested in competition. Probably 1/2 day and less than $100/person.I suppose if sailing became "easy", it wouldn't be as much fun!
Ha, 2nd choice was engr, and practicality and low finances won out.How'd that go?
Maybe in the future we can have cylinders, but holograms of conventional sails projected over them, ha.You're very right about that! A lot of the majesty and romance of it stem from aesthetics, so for a lot of people it has to look right.
Same thing with the Cyber truck, a lot of folks will hate it as the looks don't conform. But, there will also be those that love it because it breaks the rules, or just nerds like me that don't care either way but like the numbers.
Cool.Sailing is easy! Only takes a few minutes to learn the basics (a lot longer to master them). If interested and in the U.S. take an ASA or U.S. Sailing intro course. ASA is a little more tailored to those interested in competition. Probably 1/2 day and less than $100/person.