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GENERATION OF UNLIMITED ELECTRICAL POWER WITHOUT USING HYDRO-CARBONS OR NUCLEAR ENERGY 2

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dwbarlow

Civil/Environmental
Jun 2, 2015
14

GENERATION OF UNLIMITED ELECTRICAL POWER WITHOUT USING HYDRO-CARBONS OR NUCLEAR ENERGY

Sounds almost to good to be true, doesn't it? So how could it be done?

I grew up in what is called the Coulée Region of Wisconsin where the Mississippi river flows south. Along the shores of Wisconsin, Iowa, and Minnesota where there are 800 to 1200 foot bluffs, separated by some truly long valleys. What if, a series of 600 foot dams were put at the mouth of a number of these valleys which are not of any significant use. If you utilized wind energy to power water pumps and fill these reservoirs with water borrowed from the Mississippi, It wouldn't take long to store away trillions of gallons of water. When, the right point is reached, start a controlled return of the water through hydro-electric generators back into the Mississippi.

One of the current problems of utilizing wind generated electricity is that the wind is not dependable, and there is no current potential energy storage system in place to store trillions of watts of potential energy. Well, there is now, with this simple idea of using coulées that are filled with water by wind generated electricity.

OK, simple idea. Technology has been available for 30 years to make this a reality. Why are we still relying of coal and nuclear generation plants for electricity.?

It does get better. Any of you ever seen the Columbia River George between Washington and Oregon? Here, the cliff faces climb to over 2000 feet. Some of the valleys stretch 10s of miles. A few reservoirs here could potentially store an astronomical amount of water borrowed from the Columbia River. Winds sometimes blast through the George at speeds greater then 50 miles per hour. Are you getting the idea of what this simple approach could do?

I have looked this over. I do not see any major reputation damaging statements. It appears to be technically feasible. What do you think?
 
The Mississippi River slope is relatively flat in the Coulée Region and the River also freezes over in the winter. You would be limited in capacity by the flow of the River. Barge traffic would also not be able to pass.

If the Corp has not deemed it worthwhile to install turbines on the existing dams, why would you think this project is necessary?
 
Dams are being removed in the states. How is this going to fly considering fisheries and the ecology of the area. The fight an political resistance would be unsurmountable.

Try another venue...

Mike McCann, PE, SE (WA)


 
The existing dams on the Mississippi are for flood control and barge traffic. This idea does not even attempt to mess with that. What I suggest is create new dams at the mouths of existing 600 foot valleys that line the banks of the Mississippi river. Creating a network of reservoirs near the river, but separate from the river itself. I have never seen more than 2 foot of ice on the lakes in central Wisconsin, maybe up by the Great Lakes it is common.

So if a typical reservoir was 400 ft deep and 5 miles long and up to a mile wide that would be a significant storage cell of potential energy. Water intake lines from the river can be marked and be below the ice level. Water return lines could be constructed in the same way. Weather should not be an issue for such a system.

I am not a civil engineer, but I have a degree in Math and 30+ years of experience writing software for deeply embedded aerospace and defense applications.
 
The high bluffs do not have enough water since the historic drainage by the streams and other rivers drains the high areas and it is not possible to economically collect enough water. The huge number of smaller rivers and streams drain the bluff areas very efficiently. - The floods occur where there is a wide plain on either side AND a high volume of flow that people associate with the Mississippi.

There have been some plans to try to use the high bluffs along the river in MN for electrical "peak-shaving" power production using nuclear plants that are best run 24/7/365 flat out to pump the water up to storage lakes and then flowing down later through a turbine when needed to generate additional power. - It was not feasible economically, socially or practically from and an engineering or operational standpoint.

The lower Mississippi does not have enough fall in elevation for power generation, while the upper Mississippi does have more fall, but the flow is not enough. Geographically, the MSP area is the change and everything is relatively well drained by the natural erosion/geographic change through the decades.

The floods that dramatize the flow or the river are short term, so the potential tends to be exaggerated.


Engineer and international traveler interested in construction techniques, problems and proper design.
 
Your proposal is variation on "Pumped Storage" which has been discussed in reason years. In its traditional form pumped storage uses reversible hydraulic turbines operated as electric motors to pump water from the discharge back into the reservoir. The electric power to do this comes from base-loaded generating stations during off-peak hours when to maintain efficient operation coal & nuclear stations have excess electrical output available. Here is a map of many existing large commercial pumped storage stations:

Existing_Pumped_Storage_nniifj.gif


dwbarlow said:
Why are we still relying of coal and nuclear generation plants for electricity?

In three words... cost, availability, reliability. In operation, coal and nuclear can efficiently provide large, continuous amounts of electric power, 24/7, for months on end. They are typically the first choice for an electric utility's base-loaded stations. Hydro can provide some base-load power using the mandatory minimum discharge of water required to keep streams & rivers from drying up. However, the majority of hydro power is far to valuable to "waste" for base-load. A hydro station can make a "cold start" in a very few minutes and is best used for peaking-power, typically a few hours per day, often during extreme weather. In comparison, it can take the better part of day to make a cold-start of a coal or nuclear plant.

Most renewable energy, such as wind and solar, are ideal for load-following. Use these sources to directly feed power to the electrical grid when their "fuel" is available, regardless of the time of day.

The amount of electrical power used in a country such as the USA is staggering. There are nowhere near enough undeveloped hydroelectric sites to make even a dent in the power demands. When you couple this with the environmental & social impact of creating a new hydroelectric reservoir there is really little reason to actively pursue large scale hydro power. Money spent on this effort could be spent much more cost effectively on research, development, and deployment of wind, solar, geothermal, natural gas, etc. power generation. Over many decades, it may be possible to phase out coal as a major electrical power source, but it will not happen soon.

[idea]
[r2d2]
 
In almost all areas, the bottom of the theoretical 400' deep lakes or reservoirs(if they could be constructed) would be below the current level of the Mississippi, so the usable storage capacity is over-estimated.

The network of your suggested is already in place and was existed for decades as it was developed on a local basis for local practical needs.

The flow of the Mississippi is just fine, but the old, small network of upstream tributaries is very efficient. - I did catch 2 walleyes and 3 Smallmouth bass yesterday while wading in the big ditch (Mississippi) while the one of first tug barge rafts of the year passed by. Not bad water for a river running trough a metro area of about 2.5 million.

The old Mississippi River or the historic River Warren (very much older) did a good job of creating a good drainage pattern when and since the glaciers melted. Man, time and farming developed the current contributory drainage from the land on the bluffs overlooking the river.

Dick

Engineer and international traveler interested in construction techniques, problems and proper design.
 
If I did my math right, a 1 mile diameter storage tank, a mile high would have a volume of 462,431,198,085.12 cubic feet. A mile is not a significant measurement when talking about the total sq miles along major river systems in the USA. The figure, SlideRuleEra, provided shows many dams blocking water flow of river systems. I am grateful to hear of significant pump storage systems as well. But I question if that idea has been taken as far as it is practical to take it.

How many small valley storage facilities would it take before you would effectively have several of the " 1 mile diameter storage tank, a mile high" capacities? What I see when I drive from La Crosse, WI to Dubuque, Iowa on the Wisconsin side of the Mississippi river suggest enough capacity for maybe 75 such storage tanks without impeding the flow of smaller waterways like creeks or springs. Without causing any significant wildlife impact. That's a lot of reserve of potential energy.

Is technology available to build a half mile long dam, 500 ft high available? Wind along the bluff tops is consistently strong (10-20 mph) If 75 such containers were filled over a five year period, would that impact the capacity of flow of the upper Mississippi? How many wind generators would be needed to power the pumps to fill the 75 storage tanks? To me, these are questions I can't answer, at the moment. Nor is it the only idea I have. I just want to pass it along, for now and have a sense that it is being looked at, by those qualified to look at it.
 
I do enjoy the comments and misunderstandings. They help to clarify, in my minds eye, that which I am trying to describe so that others might see it as well, from a practical stand point. Let me summarize where I think we are:
1) Dam small environmentally insignificant valleys above the river level, between river bluffs.
2) Use wind generated energy to borrow water from the Mississippi to fill these reservoirs.
3) Aim for a storage capacity in a networked system in excess of 34,682,339,856,384 cubic feet
a) 75, 1 mile diameter tanks a mile high
4) Determine how much energy can then be drawn from and replaced in a average day.
5) Determine the potential cost to potential revenue
I) One Time Costs
a) 75 dams, a half mile long, and 500 ft high
b) Land use costs
c) wind turbine generator costs
d) inflow and outflow systems cost
e) water turbine costs
f) reservoir networking feasibility
II) Re-occurring costs
III) Revenue potential

6) Determine how much, if any new energy, could offset the reduced use of hydro-carbon fueled electricity generation.
7) Is it worth it?
 
Your math is suspect.

The maximum amount of power that you will generate is the energy of the flow of the River. It doesn't matter if you have a lake the size of Lake Michigan behind the dam.

The River elevation at Minneapolis is 799 and it drops to 617 in Dubuque, Iowa . A distance of 252 miles. Don't know where you are coming up with a 600 feet drop.

Between evaporation and seepage into the ground, you would lose a vast amount of water.

Hydroelectric power is wasted at night when there are few users.

The River flow diminishes in the dry season.

A dam of that size will change the weather.

The dam would cause enormous earthquakes.

The dam would be an ecological disaster.

Read about all of the problems at the Three Gorges Dam and forget the idea.


 
There is enough problems with dams in the US already.

The U.S. could be set for a catastrophic flood in the near future after 4,400 of the country's dams were declared susceptible to failure.


Pumped storage is not without problems either:


 
bimr,
The structural issues with dams should be distinguished from the concept of pumped storage.

The pumped storage generating scheme in Bath County, Virginia seems to work quite well. Like a giant storage battery, recharged by mostly nuclear power.

 
dwbarlow - I did the math for you to theoretically fill one (1) of your hypothetical reservoirs that is a cylinder 1 mile in diameter and one mile deep. To do this will require an average of 653 megawatts of power, continuously, for five years. That assumes no losses for any reasons. Of course pumps are not 100% efficient. Evaporation is an issue, but is offset somewhat by precipitation (in the subtropical climate of the southeast US, it common for electric utilities to assume that annual rainfall = evaporation). The wild card of losses will be reservoir leakage; the water pressure at the bottom of a one mile deep reservoir is 2290 psi. That will guarantee a LOT of leakage.

So we have 653 megawatts, theoretical. The typical "capacity factor" for a commercial wind farm is 25%. Therefore to average 653 megawatts will require a wind farm with 4 x 653 megawatts, or 2612 megawatts of installed capacity. Let's say you need 3 x 2612 megawatts to make up for the losses outlined above. So, IMHO, an installed capacity of 7836 megawatts is needed to fill one reservoir. At typical commercial wind turbine is rated 2 megawatts. That would be 3918 wind turbines.

For reference, at the end of 2013 the states of Minnesota, Iowa, and Wisconsin had at total installed wind turbine capacity of 9371 megawatts. The combined power of ALL wind farms, in ALL three states should be able to fill one reservoir, one time in five years. Not a very efficient use on that power resource, to say the least.

[idea]
[r2d2]
 
Hokie66,

The Taum Sauk pumped storage system was quite successful too until the operator overfilled it, then it was realized there was no overfill spillway and the dam was incorrectly constructed.

One would think nuclear units and pumped storage are relics of cheap power never to occur again. 90% nuclear efficiency * 60% pumping efficiency * 90% hydroelectric efficiency is not an efficient use of natural resources.





 
"If I did my math right, a 1 mile diameter storage tank, a mile high would have a volume of 462,431,198,085.12 cubic feet."

Actually, it is (3.14 * 5280 * 5280 /4) * 5280 = 115,550,000,000 cubic feet.
 
Yes, that was my point about dams. You can't blame the pumped storage concept for poor dam construction.

I can't agree with your "relics" argument. Things vary with time, and eventually nuclear of some type will come to the fore, combined with pumped storage in some places and not in others.
 
bimr said:
90% nuclear efficiency * 60% pumping efficiency * 90% hydroelectric efficiency is not an efficient use of natural resources.

So the overall efficiency for pumped storage is approximately 49%.

The efficiency of fossil fuel commercial electric generating stations is measured using the unit named "Heat Rate" (Thermal Power Consumed / Electrical Power Delivered). A well operated and efficient commercial sized coal fired station will have a heat rate of about 10,500 BTU / KWH (Electric). That is an efficiency of a little over 32%.

Comparing those numbers, pumped storage looks really good.

[idea]
[r2d2]
 
Nuclear power has the same problem as building a tall skyscraper. The cost of interest during construction alone is enough to kill the project. Unlike a tall building, one can not start occupying the bottom floors prior to project completion.

The reason for the relic comment is that more nuclear plants are being shut down than being constructed. The factors giving rise to uncertainty are high costs with low power prices, regulatory issues, and local concerns with safety and reliability.Pumped storage projects have less than 2% of the generation power in the US.

Among the many changes in the power business over the last 40 years, the model of central power stations is being re-thought and smaller distributed power grids are taking the place of the large units.

SlideRuleEra: Perhaps. However, the reason that many coal generating plants are being closed, is because coal is not currently an economical fuel. If you add on the societal costs of air emissions and the 7% waste solids to coal, coal is an even less attractive fuel. And that is just the cost of fuel, which does not include all of the other costs such as capital costs, water, etc.

 
75 dams, each 500 feet tall x 1/2 mile long.

The Hoover Dam alone required 5 years of pre-planning and infrastructure construction (in the pre-OSHA, pre-EPA, pre-NIOSH, pre-union, pre-federal procurement desperate-worker Depression days of 1930-1935 to build ONE 550 foot tall dam. (Grand Coulee was slightly lower, much longer. Compare against the Chinese began Three Gorges and the Russians started Aswan. Today, only a few dozen others are larger worldwide.

But 75x of them?

[pre]
Coulee
Crest Elevation ............................. 1311.08 ft
Top of Parapet Elevation .................... 1314.58 ft
Structural Height ............................... 550 ft
Hydraulic Height ................................ 380 ft
Crest Length .................................. 5,223 ft
Crest Width ...................................... 30 ft
Base Width ...................................... 500 ft
Volume of Concrete ........ 11,975,520 cu yd

Boulder Dam

Crest Elevation .......................... 1232.0 ft
Top of Parapet Elevation ............. 1236.0 ft
Structural Height ........................ 726.4 ft
Hydraulic Height ............................ 576 ft
Crest Length .............................. 1,244 ft
Crest Width .................................. 45 ft
Base Width ..... ............................ 660 ft
Volume of Concrete .......... 4,400,000 cu yd
[/pre]

Now, you want to attempt 75 of these. In today's environmental and regulatory atmosphere?
 
If coal is not an economical fuel, what is? It is still by far the most used fuel for power generation, and there must be economic reasons for that.
 
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