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https://youtu.be/o8nezU0M7mI
Air and Ocean Currents
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https://youtu.be/5tRiZG-yR24
Ocean Currents 1994 -2002
Rising sea levels will not affect our ability to harvest energy from Ocean Currents.
So, if we harvest a lot of our energy from the oceans, at least we won't be making things worse as the earth heats up. I always say that when you are in hole, it is prudent to stop digging. The ocean currents are available near most of the populated areas 24/7. We have the technology to tap that energy. This is not hard.
Here is some info on the physics of Ocean Currents. They leave out the rotation of the earth, which is behind MOST of the physics of ocean currents. But we would all be dead without rotation for many other reasons so I can understand why it such a given that it is not mentioned (i. e. assumed).
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https://youtu.be/o8nezU0M7mI
Air and Ocean Currents
https://youtu.be/5tRiZG-yR24
Ocean Currents 1994 -2002
Ocean Tides to Power More Than 150,000 Homes
Amanda Froelich, True Activist | October 18, 2015 12:09 pm
While the power plant below looks more like a gorgeous get-away than a solution to man’s energy needs, its benefits extend far beyond its beauty. As Reconstruct reports, the Swansea Bay Tidal Lagoon will use the rise and fall of ocean tides to generate enough renewable electricity to power 155,000 homes for 120 years.
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The Swansea Bay Tidal Lagoon will use the rise and fall of ocean tides to generate enough renewable electricity to power 155,000 homes for 120 years. Photo credit: Preconstruct
Though not completed at present, when the structure is finished, it will produce enough electricity to displace more than a quarter million barrels of oil each year—while leaving virtually no carbon footprint.
Power plants have been generating electricity from the oceans’ tides since 1966, but the Swansea Lagoon is the first to employ a radically new method.
How Does It Work? ???
It’s nearly six-mile-long barrier wall will enclose a huge amount of water in an artificial “tidal lagoon.” This lagoon captures and holds seawater at high tide. As the tide goes out, water in the 4.5 square mile lagoon will be as much as 27 feet higher than the water outside its walls. This immense pressure will be routed through 26 turbines, flooding out to sea until the water level equalizes on both sides of the lagoon.
The flow is reversed at high tide, keeping the sea out of the lagoon until it reaches maximum height. Then water is let go, so it may rush through the turbines until it again fills up the lagoon.
To put it into perspective, the amount of water rushing through the turbines would fill 100,000 Olympic swimming pools each day.
The Swansea Bay Tidal Lagoon will crank out clean energy as well as be used as a sports arena, aquaculture farm and seaside sculpture garden, reports GoodNewsNetwork. Its aquaculture farm will grow oysters, kelp and other local sea crops.
In addition, the lagoon can be used as a giant arena for sailing and cycling sports.
The designers of the fabulous structure plan to implement sculptures that appear to disappear into the water or rise out of it as the tides roll in and out.
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Photo credit: Preconstruct
Its location at Swansea, Wales was chosen because it has some of the highest tide differences in the U.K. This will maximize the amount of water that can be used to turn turbines and generate the 420-gigawatt hours per year.
Plans for the structure were approved by the UK Energy Ministry in June, and construction is expected to begin sometime in 2017.
The builders are presently bargaining to exchange the $1.5 billion price tag (subsidized by the government for 35 years) for approval on two more tidal lagoon plants at Cardiff and Newport.
http://ecowatch.com/2015/10/18/ocean-tidal-lagoon/
I like that. While such extreme tides are pretty rare, there are some other places this could work out. Such an elegant design, the very antithesis of a nuke plant, don't you think?
The mean tidal range in Prince William Sound is 3m. You might get a decent amount of electricity out of that.
However, how would all the Salmon get to their spawning grounds if you put one of those across the sound?
RE
RE,
Eddie is right and you are wrong. I know you will not accept that, but your premise that large tidal differentials are required for a "decent" amount of electricity is incorrect. A TINY difference, on a daily basis, is FAR more cost effective for electrical generation, and a LOT of it, than generating the SAME amount of power from fossil fuels. It hasn't been done BECAUSE the fossil fuel industry DID NOT WANT IT to be done. Thermodynamic efficiency and total required output had NOTHING to do with it.
But you can keep believing Gail Tverberg's BALONEY until the cows come home if you wish. You aren't known for altering your position on anything. You retreat into large fonts and repetition. You are a nice guy, RE. but you are as stubborn as they come. (https://renewablerevolution.createaforum.com/proxy.php?request=http%3A%2F%2Fwww.createaforum.com%2Fgallery%2Frenewablerevolution%2F3-200714183312.bmp&hash=02dafef2fe739676600fdc9bd56271f0f5ab3723)
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Yes, I'm stubborn too. ;D But I was a cornucopian three years ago, according to you. Now I'm too pessimistic, according to you. So tell me, old chum, who has failed to alter their position with new data, you or me? ;)
There is only one thing to be said about the whole "fossil fuels are the best thing since toasted bread" BALONEY:
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Dream on, fossil fuelers. The writing is on the wall for your CRAP. and it ain't gonna take 50 years for humanity to read it so you can keep trashing the planet and stuffing your empathy deficit disordered pockets. Have a nice day.
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Here are the thermodynamic FACTS about Fossil Fuels versus PV Renewable energy (for those who can read them objectively):
Renewables have higher ERoEI than fossil fuels (https://renewablerevolution.createaforum.com/proxy.php?request=http%3A%2F%2Fwww.smile-day.net%2Fwp-content%2Fuploads%2F2011%2F12%2FSmiley-Thumbs-Up2.jpg&hash=4c6cf4d5dab0f54b88dfa0c9247ae699eff03821)
One the central claims of the peak oil/energy decline movement, is that renewable sources of power have extremely low ERoEI. Therefore, it is claimed, renewables are no substitute for fossil fuels, because they cannot provide enough “net energy” to power civilization. In support of this claim, energy decline adherents often post graphs like this one, showing that renewables (especially solar PV) have low ERoEI compared to fossil fuels. More recently, Hall and Prieto have published a book, Spain's photovoltaic revolution, in which they claim that the ERoEI of solar PV in Spain is only 2.45, which is far lower than the ERoEI of fossil fuels.
In fact, those claims are entirely wrong. Renewables have ERoEI ratios which are generally comparable to, or higher than, fossil fuels. Although peak oilers reach a different conclusion, that is because they are carrying out the calculation incorrectly. They are ignoring or not including massive waste heat losses (generally 60% or more) from combustion engines which drastically reduces the ERoEI of fossil fuels. Those waste heat losses provide no energy services to society, and should be counted as losses, but are wrongly counted as "energy returns" by peak oilers. Furthermore, peak oilers are ignoring or not counting other large energy losses of fossil fuels. Those omissions exaggerate the ERoEI of fossil fuels relative to renewables. When the calculation is carried out correctly, renewables have higher ERoEI ratios than fossil fuels.
In other words, the notion that renewables have ERoEI ratios which are lower than fossil fuels, is simply mistaken. It arises from performing invalid, apples-to-oranges comparisons, or from not counting energy losses of fossil fuels.
Fossil fuels have very low ERoEI ratios
Take this graph as an example. It compares the ERoEI of solar PV for electrical power, against the ERoEI of coal and gas for heat. That comparison is invalid, because it’s an apples-to-oranges comparison. Thermal power plants (like coal-burning plants) waste approximately 2/3ds of their energy as waste heat. Waste heat is radiated out into the atmosphere from the power plant, and provides no energy services to society. This massive energy loss from fossil fuels is not counted in that graph of ERoEI, thereby artificially inflating the ERoEI of fossil fuels. If we subtract the energy losses from conversion of thermal energy to electricity, then the ERoEI of fossil fuels declines by approximately 2/3rds relative to solar PV. Conversely, we could also increase the ERoEI of solar PV by approximately 3x, thereby providing an energy quality correction. As a result, the ERoEI for thermal power plants which generate electricity is approximately 2/3rds lower than the graph indicates, or (conversely) the ERoEI of solar PV is approximately 3x higher.
It’s simply meaningless to compare the ERoEI of electricity generation from renewables, against the ERoEI of heat from fossil fuels, because heat is an extremely low-quality kind of energy which is far less capable of performing work. This is an elementary principle of thermodynamics. In order to convert heat to work, we must lose the vast majority of that heat as waste. For example, the vast majority of energy from fossil fuels is simply rejected as waste heat from power plants or internal combustion engines, and so shouldn’t be counted as an “energy return” in ERoEI calculations.
In general, the ERoEI of fossil fuels is extremely low. Natural gas may have an ERoEI of 10, but that falls to 5 when considering the massive waste heat losses emitted from natural gas turbines (generally less than half of the energy in gas is converted to electricity). Coal may have an ERoEI of 30, but that declines to 10 when considering that coal power plants lose approximately 2/3rds of the energy of the coal as waste heat.
The ERoEI of oil is particularly low because it's used in inefficient internal combustion engines inside of vehicles. Most car engines lose about 80% or more of the energy from gasoline, as waste heat, when you include both engine and transmission losses. As a result, the ERoEI of energy which actually turns the wheels of the car (rather than heating the outside atmosphere) is not 14.5 for oil, as commonly claimed, but only 2.9.
Renewable sources of energy do not suffer from those tremendous losses. Although renewables sources of energy do suffer from power grid losses, those losses are minor (usually less than 5%).
As a result, the ERoEI ratios of renewable sources of power are often much higher than their fossil fuel counterparts. Wind turbines have an ERoEI of 18, compared to 10 for coal or 5 for natural gas. Solar PV panels powering battery-electric cars have an ERoEI of about 7 (deducting grid losses and recharging heat losses), compared to 2.9 for oil in gasoline-powered cars.
Incidentally, the extremely low ERoEI of oil for driving cars and trucks (2.9), refutes the notion that an ERoEI less than 8 would lead to the collapse of industrial civilization. That claim is extremely common in energy decline circles, but it was pulled out of thin air and was wrong to begin with for several other reasons. In fact, modern industrial civilization has been growing for decades (especially China and Korea) with ERoEIs far lower than 8.
Hall and Prieto’s criticism
More recently, a book by Hall and Prieto, has become all the rage in energy decline circles. That book claims that the ERoEI of solar PV is grossly exaggerated. Hall and Prieto adjust the ERoEI of solar PV downwards, by adding all kinds of incidental energy costs. They add every incidental energy cost they can think of, like the energy costs of building fences around the solar farm, and so on. They even add energy costs for things like corporate management, security, taxes, fairs, exhibitions, notary public fees, accountants, and and so on (monetary costs are converted into energy by means of a formula). Sometimes, their estimates of those costs are absurdly high. According to Hall and Prieto, the ERoEI of solar PV is only 2.45 when all those things are added.
Once again, the calculation is incorrect, and the comparison is invalid. Hall and Prieto are adding every incidental energy cost to solar that they can think of. However, such energy costs are not included in the ERoEI calculations of fossil fuels. For example, the ERoEI of oil does not include the costs of security in the middle east, or the costs of pipelines, tankers, tanker trucks, road wear from tanker trucks, construction of gas stations, energy costs of driving to the gas station to refuel, the highway patrol, and countless other things. If those costs were counted, then ERoEI of oil (which is already low, at 2.9, when including waste heat losses) would only decline further.
It's necessary to perform an apples-to-apples comparison here. If we're going to add up every incidental energy cost of solar PV, then we must perform the same procedure for oil. Only then would we have a valid comparison.
If you carry out a detailed accounting procedure for both solar and oil, then the ERoEI of oil will be even lower in comparison, than it already was. The incidental costs of oil are almost certainly higher than those for PV. Whereas oil is a scarce substance which requires massive extraction and transportation costs, silicon is the most abundant mineral in the Earth’s crust (sand, rocks) and does not require expensive or elaborate techniques of extraction or transportation. Whereas oil comes from unstable regions and requires massive security and military costs, silicon requires only a few security cameras. Whereas oil is subject to ongoing transportation costs, silicon needs to be transported only once during the lifetime of the solar cells. In general, the incidental costs of oil are far higher than those for solar PV. As a result, if we include those incidental costs in both cases, the adjusted ERoEI of oil will be even lower in comparison than it already was.
Again, when you perform valid, apples-to-apples comparisons, the ERoEI of solar PV is higher than that of oil or natural gas. Oil for transportation in cars has an ERoEI of only 2.9 (because of waste heat losses), but that is before we include incidental costs such as security, infrastructure, and so on, so oil’s total ERoEI would only decline, and would likely be lower than 2.
Hall and Prieto’s analysis is mistaken in other ways. Their estimate of 2.45 for PV is certainly far too low. They include things like taxes and land leases, which are not energy costs, but redistributions of money. Taxes provide services for society, so they should be counted as energy returns, not energy costs. If taxes in Europe on gasoline were counted as an energy cost, then the ERoEI of oil there would certainly fall to below 1. Also, Hall and Prieto include massive energy costs for premature retirement of solar cells because of rapidly advancing technology, but those cells won't be prematurely retired because they are paid for in advance and almost free to operate at that point, regardless of their efficiency compared to newer panels (newer panels would simply be added for future projects). Also, Prieto and Hall include things like administrative expenses, employees’ salaries, and so on, using a formula for converting dollars to energy which is far too high and is just wrong. You would obtain a far lower figure by converting salaries to energy using a more reasonable formula, of dividing the entire energy expenditure of a country by its entire GDP in order to obtain a conversion factor.
A correct calculation of the the ERoEI of solar PV including everything, would be more like 6, not 2.45. You can derive this figure by removing everything from Hall and Prieto’s analysis which is not an energy cost (such as taxes or land leases), and by using a more reasonable formula to convert monetary costs to energy.
Conclusions
In short. Renewables generally have higher ERoEI ratios than their fossil fuel counterparts. When you carry out a valid, apples-to-apples comparison, the ERoEI of renewables is generally better. This is because the ERoEI of fossil fuels is actually very poor--generally less than 5--when you correctly subtract the massive waste heat losses of combustion engines, and also subtract the massive incidental costs (such as security costs) of fossil fuels.
The only circumstance where fossil fuels have a higher ERoEI for renewables is when generating heat for smelting of ores or making cement or glass. That’s because such applications do not take place inside inefficient combustion engines, and so don't require subtracting the enormous waste heat losses of such engines. As a result, such applications still favor fossil fuels. Coal has a much higher ERoEI for this purpose than solar thermal plants, and (more importantly) is much cheaper. However, those uses are only a small fraction of total energy usage. Those uses will probably be the last energy uses which are converted from fossil fuels to other sources of energy, possibly more than 100 years from now.
Not that ERoEI matters much anyway. The whole idea is a mistake. What matters is the cost (in money) of net energy, for an energy source. If the cost of net energy is low, then the ERoEI is just totally unimportant. For example, if it were possible to build a 1 GW fusion power plant very easily out of duct tape for only $10, then it wouldn’t matter at all if it had an ERoEI of less than 2. We could just build more of them, and thereby produce the same amount of net energy as a higher-ERoEI (but more expensive) energy source. As long as an energy source has an ERoEI higher than 1, the ERoEI ceases to matter, and what matters is the total cost of net energy. This is discussed further here.
http://bountifulenergy.blogspot.com/2014/07/renewables-have-higher-eroei-than.html (http://bountifulenergy.blogspot.com/2014/07/renewables-have-higher-eroei-than.html)
No, I'm not going to bother with the BALONEY from those challenging this post here. At the link above I launched into a lengthy back and forth with a fossil fueler that, to his credit, managed to be polite even when he retreated into snark from lack of an argument. The fossil fuelers here have ZERO objectivity on this issue. I no longer feed the trolls here. You know who you are. Hang on to your wallets. (https://renewablerevolution.createaforum.com/proxy.php?request=http%3A%2F%2Fwww.createaforum.com%2Fgallery%2Frenewablerevolution%2F3-200714191456.bmp&hash=a239c2fd76d20d142f1c54b961e22ebd0d2a4808)