Why not use the kinetic energy of the tides for energy

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Calin

Diamond Member
Apr 9, 2001
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Originally posted by: Gibsons
Tidal dams have been around for a while, but they're expensive to build and can disrupt ecosystems. Tidal estuaries can be very productive ecosystems and that's why there's resistance to building more. The energy prduced is otherwise clean, though.

Pretty good article here Text

In a "what if" mode, imagine a tidal dam across the straits of Gibraltar...

That wouldn't be much of a tidal dam - the Mediterran Sea losses more water to evaporation that it gets thru all other ways combined (rain, rivers). The main movement in Gibraltar is water flowing to Mediterran.
(this could be good, but the disruptions in naval traffic would be great).
 

Calin

Diamond Member
Apr 9, 2001
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Originally posted by: inspire
I've thought about AC before... I would posit that each person in America consumes about 2500 cu. ft. (300 sq. ft. x 8 ft. ceilings ~ 2500 / person) of house-space. If everyone in the US were to AC their home - how much heat would just be displaced into the atmosphere? Not even counting the heat generated in the process.

Since ICE (Internal Combustion Engines) don't hit an efficiency above like 35%, electric cars would be nice. We'd need the battery technology to support it. And, ultimately, we'd have to change the power grid, since a lot of Power Plants use ICE-like generators (we'd just be passing the buck if we didn't).

Walking is one idea. Public transit is another. I'm with you on the commuting - I drive 116 miles daily all by myself to work in a Toyota ECHO.

Another idea would be to curb the massive amount of consumerism. People go through things like cars, TV's, toothbrushes, etc. (notice I didn't say computers - those can have high turnover - just recycle them :)) like it's nobody's business. The drive to have the newest stuff just because it's shiny is outrageous. Think of the reduction in energy consumption just from not shipping all this new stuff - then manufacturing....

Public transit is good - but in neighbourhoods of houses, you would have either too many buses (running mostly empty) or too few (and everyone would use their cars instead of waiting 15 minutes for a bus). Also, purchasing food would be great if the bus stops in front of your house. If not, carrying it 100m to your house (sometime during winter, sometime during summer) won't be so attractive compared with the comfort of your heated/cooled car.
There are people that already do that, but I don't see the typical american doing it.
 

Peter

Elite Member
Oct 15, 1999
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The main point in the transport issue is, there are many things inbetween driving a 5000-lbs wannabe tank and taking the bus.

Besides, if you can't walk 100 meters with a couple of shopping bags, then that's part of the symptom, not part of the problem.
 

Pulsar

Diamond Member
Mar 3, 2003
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Peter, can I assume you are european, perhaps more specifically english?

You continue to make some of the same points I see made in other places by europeans who don't quite "get it".

First, many Americans do not drive "big" vehicles just because they feel like it. I own a minivan because I have 3 children and a dog. My next door neighbor owns a large pickup so he can tow his lawn service equipment. My father in law owns a monster SUV because he runs a boatyard and he needs to have the ability to tow boats around. My father owns an SUV because he works at said yard and needs the ability to tow boats and move tools (arc welding equipment, etc). I own a pickup because I do all my own work. When I needed shelves in my garage, I purchased lumber and built them. When I wanted to landscape my house, I purchased the material and brought it home. When my tractor or other equipment breaks, I need a way to get it to the repair shop. That's how I can afford things - by doing them myself. That's somewhat of a theme here in the US (outside of the big cities). Small or family own businesses are huge in the United States too. Huge. Construction, landscaping, etc being probably the biggest in my area.

Now on to to this whole shopping thing. In the US, shopping is not a 20 minute walk-in-walk out thing. Just standing in the lines themselves will take you 15 - 30 minutes. Grocery stores are generally 20-30 minutes away. And shopping for a family of 5? When you start going through a gallon of milk and a loaf of bread a day, two bags of groceries would become an everyday thing for most American families if they shopped in the manner you're talking about. Are you single as well? I can't see anyone with an average size family who would say they could go get two bags of groceries a week and be done with it. It doesn't work that way.

Believe it or not, the majority of Americans still live in Rural locals. Unlike Europe, England, etc, where the majority of people live in cities. Land in the US is still quite abundant and still quite cheap: my friends from Europe were flabbergasted when they saw the house and lot I own on a very small salary.

As such, blanket statements like you're making don't fit. Mass transit has been worked on for decades in a major city (+1 million population) that I live near. However, it just doesn't work because the majority of people don't live in houses jam packed side by side. When you start talking about 2+ hour commutes on buses and exhorbitant charges to maintain the system, it just doesn't work.

I do not ride a bus because there are not buses near where I live. Yet, I live 10 minutes from my job (8 miles).

Many of the basic things that allow high density populations to live in the manner you're suggesting simply are not present in the United States, and probably will not be for another couple hundred years.

That isn't to say that any Americans aren't wasteful - many are disgustingly so. Nor does it mean that all Americans wouldn't benefit from mass transit. In the places where it makes financial sense, it has been done - New York, L.A., San Fran.

Some ideas - like raising the taxes on gasoline, would help drive less consumption. We're already beginning to see a major shift in purchasing of vehicles here in the US. There are already additional taxes on larger vehicles as well.

When people talk about consumption and resources in the US, they have to realize that the only thing that will drive savings is an increase in cost. And our government, and our people, will never support the social engineering required to do so through taxation. Perhaps that is selfish - but you know what they say about people who live in glass houses.
 

bobsmith1492

Diamond Member
Feb 21, 2004
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Originally posted by: LsDPulsar
Peter, can I assume you are european, perhaps more specifically english?

You continue to make some of the same points I see made in other places by europeans who don't quite "get it".

First, many Americans do not drive "big" vehicles just because they feel like it. I own a minivan because I have 3 children and a dog. My next door neighbor owns a large pickup so he can tow his lawn service equipment. My father in law owns a monster SUV because he runs a boatyard and he needs to have the ability to tow boats around. My father owns an SUV because he works at said yard and needs the ability to tow boats and move tools (arc welding equipment, etc). I own a pickup because I do all my own work. When I needed shelves in my garage, I purchased lumber and built them. When I wanted to landscape my house, I purchased the material and brought it home. When my tractor or other equipment breaks, I need a way to get it to the repair shop. That's how I can afford things - by doing them myself. That's somewhat of a theme here in the US (outside of the big cities). Small or family own businesses are huge in the United States too. Huge. Construction, landscaping, etc being probably the biggest in my area.

Now on to to this whole shopping thing. In the US, shopping is not a 20 minute walk-in-walk out thing. Just standing in the lines themselves will take you 15 - 30 minutes. Grocery stores are generally 20-30 minutes away. And shopping for a family of 5? When you start going through a gallon of milk and a loaf of bread a day, two bags of groceries would become an everyday thing for most American families if they shopped in the manner you're talking about. Are you single as well? I can't see anyone with an average size family who would say they could go get two bags of groceries a week and be done with it. It doesn't work that way.

Believe it or not, the majority of Americans still live in Rural locals. Unlike Europe, England, etc, where the majority of people live in cities. Land in the US is still quite abundant and still quite cheap: my friends from Europe were flabbergasted when they saw the house and lot I own on a very small salary.

As such, blanket statements like you're making don't fit. Mass transit has been worked on for decades in a major city (+1 million population) that I live near. However, it just doesn't work because the majority of people don't live in houses jam packed side by side. When you start talking about 2+ hour commutes on buses and exhorbitant charges to maintain the system, it just doesn't work.

I do not ride a bus because there are not buses near where I live. Yet, I live 10 minutes from my job (8 miles).

Many of the basic things that allow high density populations to live in the manner you're suggesting simply are not present in the United States, and probably will not be for another couple hundred years.

That isn't to say that any Americans aren't wasteful - many are disgustingly so. Nor does it mean that all Americans wouldn't benefit from mass transit. In the places where it makes financial sense, it has been done - New York, L.A., San Fran.

Some ideas - like raising the taxes on gasoline, would help drive less consumption. We're already beginning to see a major shift in purchasing of vehicles here in the US. There are already additional taxes on larger vehicles as well.

When people talk about consumption and resources in the US, they have to realize that the only thing that will drive savings is an increase in cost. And our government, and our people, will never support the social engineering required to do so through taxation. Perhaps that is selfish - but you know what they say about people who live in glass houses.

:thumbsup:
 

Peter

Elite Member
Oct 15, 1999
9,640
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I'm German - and I've been to various parts of the US. I've seen dense, rural, and middle-of-nowhere (and I've had to sustain myself in those circumstances) - and I've seen the general attitude.

Yes, things are different (closer together, mostly) in Europe. What's also different is that we've had high energy cost and government regulations that force (force!) private sector energy usage down for quite a while. The US are lagging behind in this. No matter whether your house is on Main Square in the big city or in the middle of nowhere, you can still insulate it properly. For example, we have regulations here that don't even LET you build an energy inefficient house - and if you remodel an existing one, you have to adhere to the same rules. Even if you do nothing, the regulations apply when you sell or rent it out.

When buying a car, look at its consumption. This /is/ starting to work in the US, even though fuel still costs only half as much as over here. When moving to a new place, check whether the infrastructure serves your daily needs. (With the shops nearby, then you can go buy a luggable load of fresh food every day, rather than a truckload of processed and packaged "food" once a week.) Lots of things, each one a baby step towards lower consumption of energy and matter. Yes this requires certain lifestyle changes. We simply can't sustain this one for very much longer.

It starts in the head. Like I said further above, think about what YOU can do, and then do it. For example, did you ever consider riding a bike to work? Eight miles, in an area with (the way you describe it) little traffic.
 

imported_inspire

Senior member
Jun 29, 2006
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Just a few things...

Biking 8 miles to work? That's more than a small step ;)

Buying groceries once or twice a week for a lot of folks is more time-efficient. I mean, if you're going to have to drive to the store (like if you have little kids), it's more eco-friendly and energy efficient to plan your trips and load up when you go to the store or market. Having a refrigerator lets us keep fresh food fresh longer, so there's not a driving need to go to the grocery daily.

I think the problem with the infrastructure arguement is that the infrastructure you're talking about does not exist in the majority of US cities.

Of course, necessity is the mother of invention - if prices get too high over here, we will have to stop complaining about high energy costs and we will do something about it. That's how our capitalistic economy functions. I just don't think we're in the same shape energy-wise as Europe and I think that's why we're 'lagging behind' as you put it, peter.

Outside of the governmental regulations, I agree that there are plenty of personal decisions that can be made to reduce energy consumption in the US, and in our society, that's where it's going to have to start - at the consumer level.
 

Peter

Elite Member
Oct 15, 1999
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Of course it has to start in the individual's mind - that's what I'm saying.

Most of the nonexistant infrastructure is a self-sustaining problem. Just one example: As long as people willingly drive half an hour to the megastore, there's simply no need for a grocery store on the corner, and they'll all close or nobody will even bother open one in a newly built community. Here in Europe, we've gone through this as well, with bakeries, butchers and everything closing shop, and the supermarkets taking over. It's been bouncing back during the past few years, mainly driven by immigrants doing the corner shop thing, but also by a move back to fresh and natural food.

YOU need to change stuff best you can. "But it's inconvenient" is exactly what got us where we are now.
 

MrPickins

Diamond Member
May 24, 2003
9,117
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Talk about a thread hijack. Can't we keep this stuff in P&N?

Originally posted by: RossGr
There are several schemes in place which seem promising to harness wave action for power. Here is one actually producing power in Portugal.

That looks like a neat idea. The waves bending the joints is what generates the power?
 

imported_inspire

Senior member
Jun 29, 2006
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Originally posted by: virtualgames0
Tides are perpetually moving. They could be used to move turbines.
I'm guessing it doesn't work which is why it's not used
Anyone know why?

The OP asked why Tidal Energy has not been implemented. We were discussing how infrastruture, political policies, and culture influence the very phenomenon the OP was inquiring about.
 

Pulsar

Diamond Member
Mar 3, 2003
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In the US, Tidal production has gone the same way as wind farms, solar, nuclear, and water-driven.

It is still less cost efficient than fossil fuels, and as such will not be studied here until it becomes significantly more cost efficient.
 

Peter

Elite Member
Oct 15, 1999
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... and as long as you keep from studying alternatives, oil will conveniently remain interesting. Anyone expected differently from your oil funded government?
 

imported_inspire

Senior member
Jun 29, 2006
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Alternatives are being studied. There's been a 20 year moratorium on drilling in the US. I think now this belongs in P&N.
 

RossGr

Diamond Member
Jan 11, 2000
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Originally posted by: MrPickins
Talk about a thread hijack. Can't we keep this stuff in P&N?

Originally posted by: RossGr
There are several schemes in place which seem promising to harness wave action for power. Here is one actually producing power in Portugal.

That looks like a neat idea. The waves bending the joints is what generates the power?

That's right. The bending joints drive hydrolic pumps which drive a generator. These will be useful in all costal areas.
 

BrownTown

Diamond Member
Dec 1, 2005
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OF course the enviromentalists will hate it since you are sticking a bunch of these giant red turds out in the ocean. Seems to me just looking at it that this method cannot be all that cost effective since your gonna need all that generation hardware in each one, and also likely a step-up transformer to increase transmission efficiency to the shore. If you want something highly technical maybe someone can have fun talking about the rammification of high voltage power transmission lines underwater seeing as the dialectric constant of water is 80 times that of air which would greatly increase the parastic capacitance to ground.
 

bobsmith1492

Diamond Member
Feb 21, 2004
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Not to mention salt water is a decent conductor, so you'd need insulated cables anyway..... you weren't saying just to string bare transmission lines like the overhead ones, were you??
 

Calin

Diamond Member
Apr 9, 2001
3,112
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Originally posted by: Peter
The main point in the transport issue is, there are many things inbetween driving a 5000-lbs wannabe tank and taking the bus.

Besides, if you can't walk 100 meters with a couple of shopping bags, then that's part of the symptom, not part of the problem.

Do you drink bottled water? Try taking two 6-packs of 1.5l or 2l each (half a gallon bottles, let's say) for a walk for more than 100m. Or maybe 10 pounds of potatoes, 2 pounds of tomatoes, two bottles of edible oil, and some other assorted food stuff.
Anyway, I am not talking about walking 100m - from my apartment to a market I go thrice the distance, to a big shop I go even farther. I really prefer to pay more for things like water and buy them from a shop in the next building (but I have this shop nearby)
 

Calin

Diamond Member
Apr 9, 2001
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Originally posted by: MrPickins
Talk about a thread hijack. Can't we keep this stuff in P&N?

I might have contributed to the thread hijack - but I am glad for Peter's answer. Puts a new light on some things
 

BrownTown

Diamond Member
Dec 1, 2005
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I'm talking about underwater power cables, they must have them somewhere to get power out to islands and stuff, i was just wondering what is done to combat the problems invovled, the additional insulation is another annoying problem that will increase costs, and likely decrease efficiency.
 

TheInternal

Senior member
Jul 7, 2006
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Renewable energy isn't nearly as profitable or yielding of short term returns as fossil fuels... hence greed > progress/ preventing our destruction from jacking with the environment
 

imported_inspire

Senior member
Jun 29, 2006
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Well, that's how capitalism works.

Here is something you folks might find interesting. Inconsequentially, it's funded by a NSF grant and the research is being conducted at Ohio University.
 

BrownTown

Diamond Member
Dec 1, 2005
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This whole "off the grid" stuff is just total BS, its alot more efficient and economical to produce things on much larger scales and pipe the power to individual users via transmission lines. Transmission losses are only a few percent, and it makes no sense for every home to have batteries. There is already a way to store energy that is ~75% efficicent which is likely alot mroe than these fuel cell storage solutions can provide, and much safer and cheaper than batteries. Pumped water storage is currentlythe solution for storage of energy produced by varrying power supplies of things like wind and solar. Also, centrallized power production means more efficent large scale solar and power installations can be used. And solutions like nuclear which would make no sense on a smaller scale can be used. Also, getting rid of coal just doesnt seem like all that great idea given that the US is completely loaded with coal which is still a very economical power solution. It might be good to try to intruduce "cleaner" sources of energy right now like nuclear and wind, but we need to be a little more sure about this whole global warmin-CO2 link before we make radical changes.
 

TheInternal

Senior member
Jul 7, 2006
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the link has been confirmed many times over during the last half decade, BrownTown. Discovery channel, NBC, and I believe the BBC as well coproduced a documentary starting Dan Rather talking to doctors in all sorts of fields about how mankind is indeed screwing the ecosystem with CO2 emissions. Al Gore helped produce a movie about the same issue. Discovery channel is also airing other documentaries regarding the topic.
This is NOT a political issue anymore. It's a survival issue.

That being said:

category 6 (yes... I said "6") hurricanes, droughts in sub-tropical regions, and flooding in dessert regions > using fuels that exponetially increase severe weather patterns/global warming

To many folks are using the economy as a reason to stop making the changes that are needed immediately to help prevent/slow cataclismic environmental changes. The stuff I've been seeing/reading from reputable sources (such as that Dan Rather thing I mentioned) are SCARY. America and China in particular need to get their acts together in this regard.
 

Peter

Elite Member
Oct 15, 1999
9,640
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Originally posted by: CalinDo you drink bottled water?

Nope. Thanks to our city having been very restrictive in protecting their water reservoir areas and maintaining the city's water grid, we have excellent, chlorine-free tap water. (Which, perversely, is also being bottled, and can be bought in shops for 1000 times the price.)

Try taking two 6-packs of 1.5l or 2l each (half a gallon bottles, let's say) for a walk for more than 100m. Or maybe 10 pounds of potatoes, 2 pounds of tomatoes, two bottles of edible oil, and some other assorted food stuff.

Two-wheel trolley, sorted. Particularly if it's just ...

Anyway, I am not talking about walking 100m - from my apartment to a market I go thrice the distance, to a big shop I go even farther. I really prefer to pay more for things like water and buy them from a shop in the next building (but I have this shop nearby)

... a few hundred meters to walk. This is not a Mount Everest expedition, it's a short walk.
Besides, aren't any of your children old enough to get their butt off the sofa and help you with the shopping? Four hands carry more than two ;)

Nicely demonstrated: It's all about figuring out the possibilities, not dwelling in the Icants and Idontwannas.
 

imported_inspire

Senior member
Jun 29, 2006
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I wouldn't blanket off the grid solutions as total BS - they're useful in certain situations. For example, many homes in lower St. Bernard Parish are still without power after Hurricane Katrina. The infrastructure for centralized power takes awhile to rebuild. Other folks may enjoy not having to rely on centralized power. The link I gave was just trying to show how the US was engaged in researching alternative power sources; I don't know much about the feasibility (but that is what they're studying...).

I've never heard of pumped water storage - do you mind explaining it or giving a link?

Global Warming is still debated. I won't debate Global Warming here, I'll simply say that scientists still disagree and proof by popular opinion isn't a proof. I personally don't think our lifetime will necessarily yeild a definitive answer on the subject. We do know that Coal and Oil and Natural Gas will one day no longer be more efficient than renewable sources.