A Modest Proposal

[Harold Squared]

Those of you who have been kind enough to take an interest in my posts may have noticed that I am acutely aware of the limitations of renewable energy projects.

 

In the past, however, I was quite a champion of these and in some ways maybe I still am. For example, wind energy would be better harnessed by the blade hub driving a crankshaft connected to an air compressor rather than a generator, particularly in an offshore application, where wave energy could be stored by the same means in submerged air tanks.

 

This source of compressed air could be tapped at will to drive a turbine and render the power stored as dispatchable as hydroelectricity, helping the grid meet periods of peak demand.

 

Unfortunately such an installation would be vulnerable to storms except perhaps for the submerged tanks but at the moment that is the principal drawback as far as I can see and applies to wind energy generally.

 

Your thoughts and comments are most welcome as usual and I thank you in advance for the feedback.

Edited July 30, 2015 by Harold Squared

[Strange]

 

or example, wind energy would be better harnessed by the blade hub driving a crankshaft connected to an air compressor rather than a generator,

 

Do you have some calculations, or a reference, to show this is true?

[Klaynos]

I'd be interested in seeing efficiency comparisons to other energy storage mechanisms, e.g. water storage, hydrogen from electrolysis, etc...

[OptimisticCynic]

Tanks are generally expensive to construct. There are some examples of compressed air storage in caverns.

http://energystorage.org/compressed-air-energy-storage-caes

 

On a small scale, wind directly pumping water to a high tank for later use in a micro hydroelectric turbine generator system seems more economically feasible to me.

 

This would be easier for sections of cities that are built on hilly ground. What is problematic is that developers prefer to build on flatter areas.

 

What does this have to do with Earth Science?

[Harold Squared]

I was just musing and admit the connection to earth science is tenuous. The notion is that it is necessary to generate electricity by not burning stuff, ergo, wind power, which does not provide said power on demand.

 

A good number of such installations are located offshore where hills and caverns are conspicuously absent. By running current through wire mesh armatures, minerals can be induced to precipitate out of seawater rather economically.

 

I propose storing mechanical energy as compressed air since it is the most direct way of doing so vs converting it first to electricity, electrolysis of water to hydrogen, and then conversion to electricity from hydrogen, for example.

[Strange]

I propose storing mechanical energy as compressed air since it is the most direct way of doing so vs converting it first to electricity, electrolysis of water to hydrogen, and then conversion to electricity from hydrogen, for example.

 

How does the cost and efficiency of this of this compare to alternatives such as producing hydrogen, pumped hydroelectric, batteries, etc.

[Klaynos]

I was just musing and admit the connection to earth science is tenuous. The notion is that it is necessary to generate electricity by not burning stuff, ergo, wind power, which does not provide said power on demand.

 

A good number of such installations are located offshore where hills and caverns are conspicuously absent. By running current through wire mesh armatures, minerals can be induced to precipitate out of seawater rather economically.

 

I propose storing mechanical energy as compressed air since it is the most direct way of doing so vs converting it first to electricity, electrolysis of water to hydrogen, and then conversion to electricity from hydrogen, for example.

Do you have any numbers to back up your assertions?

[DrP]

This looks promising, no? I much prefer solar power to wind power - makes a lot more sense to me long term. www.scienceforums.net/topic/90185-large-scale-solar-plant-in-gobi-desert/

[CaptainPanic]

This looks promising, no? I much prefer solar power to wind power - makes a lot more sense to me long term. www.scienceforums.net/topic/90185-large-scale-solar-plant-in-gobi-desert/

 

Funny that you choose a Chinese investment: The Chinese are by far the largest investors in sustainable energy. And that always makes me wonder: If sustainable energy was such a bad idea, then you wouldn't expect that they would invest so much, as the Chinese government obviously doesn't have to please the tree-huggers in the next elections.

 

Source for the claim that the Chinese are the biggest investors: Bloomberg report (see page 10 for most comprehensive chart of 2014 investments) Note: .pdf warning

[Harold Squared]

Do you have any numbers to back up your assertions?

There are potential losses whenever such conversions occur so it makes sense to minimize them. The major advantage of the plan described is essentially storing wind energy for use at periods of peak load, similar to hydroelectricity. Need more power, turn a valve. And being entirely pneumatic up to that point, fewer problems with electricity in the marine environment can be anticipated.

 

Also, the tanks need not have bottoms, being inverted reservoirs like giant diving bells.

Edited August 11, 2015 by Harold Squared

[Strange]

That's a no, then. (As usual.)

[DrP]

So, 'no' then...

Ha - syncro posting.....

[Harold Squared]

That's a no, then. (As usual.)

Yes. And since I have your attention, sir, awhile back I made some comments regarding your personal safety which might have seemed flippant. I regret them and would like to make amends here. I am pleased that up until now you have not been victimized by crime.

 

I can assure you from personal experience that it has little to recommend it.

 

Off topic but I tried and failed to say as much by other means.

[DrP]

Personal safety? wot you on about?

[Strange]

I assume he made some sort of veiled threat/insult (1). But because most of his posts are almost totally content free, I completely missed it.

 

(1)

Slartibartfast: Come. Come now or you will be late.
Arthur: Late? What for?
Slartibartfast: What is your name, human?
Arthur: Dent. Arthur Dent.
Slartibartfast: Late as in the late Dentarthurdent. It's a sort of threat, you see. I've never been terribly good at them myself but I'm told they can be terribly effective.

[Harold Squared]

So, 'no' then...

 

Ha - syncro posting.....

Hi, Doc. Deserts are of course obvious locations for solar installations, insolation is high and land prices are low. Even so, there are generally seasonal fluctuations, e.g., the so called "monsoon" season of Arizona.

[Strange]

Hi, Doc. Deserts are of course obvious locations for solar installations, insolation is high and land prices are low. Even so, there are generally seasonal fluctuations, e.g., the so called "monsoon" season of Arizona.

 

Of course, you have looked into the costs of getting the energy from there to where it is needed?

 

Or not ...

[Harold Squared]

I assume he made some sort of veiled threat/insult (1). But because most of his posts are almost totally content free, I completely missed it.

 

(1)

Slartibartfast: Come. Come now or you will be late.

Arthur: Late? What for?

Slartibartfast: What is your name, human?

Arthur: Dent. Arthur Dent.

Slartibartfast: Late as in the late Dentarthurdent. It's a sort of threat, you see. I've never been terribly good at them myself but I'm told they can be terribly effective.

I did imply that you might have nothing worth stealing, in as many words. One's peace of mind is beyond any monetary valuation.

 

Regrettably, there are those who would do harm for nothing more than their amusement.

 

Returning to the topic, wave energy could be harvested by such means by connecting pipes with check valves to floats. The entire assembly could function as a breakwater for a harbor or other area requiring erosion abatement.

 

Of course, you have looked into the costs of getting the energy from there to where it is needed?

 

Or not ...

That is one of the persistent problems of renewable energy. I daresay more power consumers live near the ocean than the desert but there are notable counterexamples of course.

 

Nuclear power is completely site independent, of course.

[Klaynos]

So no numbers to back up your claims. Why should we bother pursuing this without even a cursory feasibility analysis of efficiency compared to other methods?

[Strange]

Returning to the topic, wave energy could be harvested by such means by connecting pipes with check valves to floats.

 

Can it? With what efficiency? And what costs?

 

Why not just set up a giant treadmill powered by unicorns?

[Harold Squared]

 

Can it? With what efficiency? And what costs?

 

Why not just set up a giant treadmill powered by unicorns?

Unicorns are based upon traveler's tales about what we now know as the rhinoceros, a vile tempered beast resistant to domestication. You are welcome to try your luck with this approach but it is off topic.

So no numbers to back up your claims. Why should we bother pursuing this without even a cursory feasibility analysis of efficiency compared to other methods?

Because it addresses a primary deficiency of wind power, it is not dispatchable. Incorporating wave power should give us some sort of minimum baseline, too. And when someone develops the idea to that point, the engineering section of the board might be a more appropriate venue.

[Strange]

Because it addresses a primary deficiency of wind power, it is not dispatchable. Incorporating wave power should give us some sort of minimum baseline, too.

 

How do you (or we) know that, as you have provided no numbers to back up your claim?

[Harold Squared]

 

How do you (or we) know that, as you have provided no numbers to back up your claim?

Waves are pretty much constant but wind is extremely variable. By harvesting the energy of such sources on an "as available" basis and storing it as compressed air we can later release that energy on demand, as hydroelectricity does. It is sort of an inverted version of hydropower, only driven by pressure rather than gravity. Edited August 11, 2015 by Harold Squared

[Strange]

Waves are pretty much constant but wind is extremely variable. By harvesting the energy of such sources on an "as available" basis and storing it as compressed air we can later release that energy on demand, as hydroelectricity does. It is sort of an inverted version of hydropower, only driven by pressure rather than gravity.

 

Can you provide any data to support these guesses?

[Klaynos]

To take this idea seriously I'd need to see numerical (and the calculations used) answers to at least these questions:

 

1. What is the efficiency of this storage medium compared to others?

 

2. What volume of storage is required for say 20% of a wind turbines daily output compared to other methods?

 

3. What is the rough cost of development and certification?

 

4. What are the maintenance costs compared to other methods? (I'd suggest comparing other similar technologies for this one)

 

5. What's the wrist case scenario when things go wrong?

 

6. How easily can the storage capacity be changed?

 

I don't want now assertions and handwaving.

 

Can you provide any data to support these guesses?

It's just wrong. Waves are wind driven. Any surfer will tell you waves are anything but consistent.