If it is in the water, it could interact with the ecology and require a maintenance schedule for cleaning, grilles to keep large objects and animals out, and a way to keep plants from clogging it, but what do I know, I guess they have considered all of these needs. Fine with me, good use of 'free'power
Another tidal unit running on air and using wave action was built into a concrete bunker, and as the vaves rose and fell, the hydraulic pressure forced the air through an axial fan, one way then in reverse, generating power. It seemed very noisy, but this annoyance could be solved by locating as many of them as possible adjacent to the sparsely-opulated wealthy people's properties, thereby reducing the number of citizens annoyed in more densely populated sections of coast. (yes it is humor)
Discussion on:
Top
Rated
Rated
I recall reading an article 20+ years ago...
Edited by JohnMcGrew@...
Updated - 28th Sep
Just
In
In
really interesting
Posted by aflemo
5th Oct
Show:
+1
Vote
This one goes in the water.
Posted by opcom
28th Sep
+1
Vote
I recall reading an article 20+ years ago...
...where the effects of an experimental tidal installation somewhere in Europe were able to be measured by minute changes in the Earth's rotation/wobble. It makes sense; after all, there is no free lunch. The real question is if the unintended consequences of tidal power is comparable to the known and suspected consequences of carbon-based power. As with "cold fusion", I fully expect there to be those who object to this for some real or imagined ecological impact.
One big advantage is that unlike with wind and solar, tides are completely predictable, and the energy collected from these installations is more easily integrated into the grid.
The other big question is simple economics: Does the cost of building and maintaining these installations make them competitive? How much maintenance will they require? How long will they last? As anyone who has lived near the sea or has owned a boat will tell you, the ocean is the most hostile environment to modern engineering. Mechanical components that can be expected to last for decades on shore only survive for years or months in chemically and biologically active salt water.
I will be very interested to see how effective & efficient these installations really are, when all costs are considered. The ocean represents a phenomenal amount of potential energy.
One big advantage is that unlike with wind and solar, tides are completely predictable, and the energy collected from these installations is more easily integrated into the grid.
The other big question is simple economics: Does the cost of building and maintaining these installations make them competitive? How much maintenance will they require? How long will they last? As anyone who has lived near the sea or has owned a boat will tell you, the ocean is the most hostile environment to modern engineering. Mechanical components that can be expected to last for decades on shore only survive for years or months in chemically and biologically active salt water.
I will be very interested to see how effective & efficient these installations really are, when all costs are considered. The ocean represents a phenomenal amount of potential energy.
Posted by JohnMcGrew@...
Updated - 28th Sep
0
Votes
Rance
At least some of your questions are answered by the continued operation of the Rance Tidal power station (as mentioned in the article). It operates today, 46 years after construction. Wiki says it cost E94.5 million and took almost 20 years to pay for itself. This style of tidal generator (ie. barrage) is essentially the same as a dam and they can operate for very long times--some say for 120 years; Hoover dam has been generating power for 76 years so far.
It may be different for the tidal flow type turbines as described here but they can access vastly more potential sites with much less environmental concerns.
It may be different for the tidal flow type turbines as described here but they can access vastly more potential sites with much less environmental concerns.
Posted by rhodez
Updated - 29th Sep
+1
Vote
We've studied tidal energy harvesting for decades,
--but are no closer to economical systems than we were in the mid-20th century. The answer to J. McGrew's doubts are "It's tougher than you can imagine." Both initial cost and maintenance are far in excess of energy returns. But the biggest roadblock is scarcity of locations that have enough potential tidal energy to be worth it if we COULD economically boost output. San Francisco Bay is a possible source of strong, sustainable tidal flow and is close to users and the distribution network; but I think that's all there is in the USA. The best in this Hemisphere probably is the Bay of Fundy; but nature has provided little else. Efforts to capture energy in these "best" spots have so far defeated development efforts. But the point is, such locations with reachable locations and adequate energy potential, even with some great tech breakthrough, are too rare worldwide to ever add significant shares of world power.
Posted by TerraSmith
29th Sep
0
Votes
sites
I think you'll find current developments are aimed at much lower tidal flow sites than the super-sites you mention. And I think your overall conjecture is wrong. There is no reason why these kind of turbines should cost too much more than wind turbines, in fact quite feasibly less. The big point is that in a moving liquid a turbine is vastly more efficient than air so the turbines can be much smaller. The other point of course is that tidal flow is totally reliable and predictable so this is a big factor in driving research to harvest the lower flows that are universal on all coastlines. Just like there is massive energy potential in winds, the trick will be to get the capital cost, and efficient lower-energy capture right. Don't discount it.
Posted by rhodez
29th Sep
0
Votes
Japan
Incidentally this is the "glass half full" story from the Fukushima accident. That is, with nuclear gaining political untouchability the big industrial powers like Germany, France and now Japan can focus their industrial might on alternatives. With their huge coastline it is a no brainer that Japan should also look at tidal/ocean power. There is a lot of discussion about them going towards offshore wind power (because it is a huge resource for them) but I wonder if they should not go straight to tidal because offshore wind turbines are very expensive and still require the same kind of infrastructure as tidal (eg. getting the power back to shore; tethering huge structures in deep water).
Posted by rhodez
29th Sep
0
Votes
Alaska
the Anchorage strait is almost as good as the bay of Fundy. Both are much better than San Francisco Bay.
Posted by YetAnotherBob
2nd Oct
+1
Vote
Been economical for decades
The first installations were "tidal barrage" projects - basically, putting a dam across an estuary to trap the water at high tide, run it though turbines when the tide goes out. A few stations of this type have been running economically for years. Locations where you can do this are very rare, though.
The "in stream" turbines such as pictured above are another matter. More places they could be used, but not yet a proven technology.
The "in stream" turbines such as pictured above are another matter. More places they could be used, but not yet a proven technology.
Posted by Greenknight_z
29th Sep
0
Votes
really interesting
This is really interesting. Alternative energy or "green" energy is a good choice for all countries to save resources and reduce the cost. ryska kvinnor
Posted by aflemo
5th Oct