the Air Vent

Because the world needs another opinion

Greenthink

Posted by Jeff Id on July 9, 2010

First there is no such thing as renewable energy, it’s kind of fitting that the very word greenies have coined is itself a lie. I say that because there are so many lies and exaggerations in the world of green energy that it makes ‘renewable’ a perfectly fitting term.  The second law of thermodynamics makes sure that the energy we convert is extremely difficult to recover, in a perfectly efficient system you could convert your CO2 back into gasoline but of course it would take as much ‘work’ as you just got out of it.  In reality, the energy you used to drive your car is already turned completely into heat within a two minutes of being turned into velocity (think how long it would take to coast to a stop if you shut off the engine).

Alright, renewable is an intentional misnomer, so what.

Well it makes people think of energy as recyclable creating beautiful symbols like this:

The symbol itself is a lie, the engineer in me cringes at green energy being diagrammed like this.

Green energies such as wind, wave, solar electric, hydroelectric, and solar thermal, biofuel, etc. all have one thing in common.  They are all forms of solar power.  It takes energy from the sun to drive wind, wave and create plant fuels.  Another form of solar power is oil and coal, they are a form of very inefficiently stored solar energy from millions of years ago. Nuclear fission is also a form of solar if you take it back to the stars believed to have created the heavy elements used in the fission process.  However, both fossil fuels and Nuclear used energy from stars which has been stored in relatively convenient packages for release by the right equipment at a moments notice.  I call the other forms of energy stored solar, whereas instant solar, which is now being incorrectly called renewable energy, trickles in at a low density per unit area which requires the construction of massive area consuming collection zones.

The amount of area used with today’s horribly inefficient solar technologies, means that green energy or instant solar’s viability is determined by collection efficiency rather than cost alone.  The reason is that if we were to use ‘corn’ to power our cars in the US, even basic calculations show that we would need more than all the land mass of the North American continent to be a producing viable corn field, and more sophisticated calculations show that we may be net loosing energy by corn ethanol. Basic calculations on algae biofuel produce equally ridiculous results like two land masses the size of Texas to drive all the US cars — only.  Again more sophisticated calculations will produce even worse results.

Super Algae Bio-Diesel Energy

The point is that the land usage is too great to make them viable.  These technologies are environmental disasters waiting to happen.  But they’re renewable Jeff!!

Nope.

They are instant solar, and instant solar doesn’t have the energy to power your car/train/truck.  The energy density is not practical for cars.  This means that energy storage is the key.  Storing the collected solar power as oil, is the key advantage of biofuels, the maximum efficiency of photosynthesis is pegged at something like 9% but most of that powers the plant so your max efficiency of light collection by plant is very very low.  Besides that though, we really don’t have a way to store other forms of solar energy efficiently.  Nature really doesn’t either, so it takes millions of years time and the sun just throws a few gagillion extra joules at the problem.  None of this means that efficient (and safe) storage can’t be achieved, it just means that we haven’t figured it out yet.

I think that within reason that the numbers show, a 20% efficient solar collection makes good sense, this is just based on some rough calculation and some thumbnail guessing.  There are several companies which have achieved this kind of efficiency for solar, but my preferred number is a year round efficiency collected and stored.   Is this achievable in the future, in my opinion it’s guaranteed in the future and probably can barely be done with certain technologies today but biofuel will NEVER make the cut. The god of physics said NO and there is nothing you can do about it unless you re-engineer chlorophyll.  I’m pretty sure we don’t want to create quadrillions of microscopic plants which collect more energy, more easily, than anything on Earth but down the road our command of genetics may make it possible to control such a beast.  If it got out of hand, we could just make it sick or something.

Of course then you come down to the biggest problem of all —- cost.

In order to make instant solar a workable technology, we cannot as a species pay four times more for it than we currently do.  Our societies are barely out of the trees in my opinion, and we give ourselves far too much credit.  Science and energy have transformed our lifestyles to better standards than kings 300 years ago.  One way to ruin that standard is to limit our available and usable energy.  Of all things the greenies want to do, this is the most dangerous and frankly ignorant point.

Consider Obama’s two billion recently spent on solar energy production.

1.45 Billion went to a plant which is claimed will generate 250 megawatts which is again claimed to power 70,000 homes.  A megawatt is a million joules of energy per second or energy per time.  So we have 250 million/70,000 homes = 3571 Watts/household at full production capacity.  When you consider that those watts are available for less than half the day, and follow a roughly sinusoidal distribution of collectible energy, the average power level will drops to about 700 watts per household.  (integrate sine to find pi/8 centroid of the sine and divide by 2 for daylight hours). You can see that it’s not really enough to power 70,000 homes all day long.

But if it were enough, the program claims to create 1500 jobs, green jobs right, anyway if those permanent jobs are used to support the plant, it amounts to about 1500* (60,000USD/Yr labor) /70,000 homes = 1285 USD in labor cost incurred by those homes.  Or $100/month for labor alone – with no profit for the company yet. If they put 1.45 billion/70,000 homes the investment – per home is 20,700USD.  Just the interest on an investment that large will be around $150/month (rough low estimate which depends on unknown terms).   So now for those 700 continuous Watts per month, we have tied up $250 USD in labor and interest.

Kilowatthours are what are billed by energy companies – 1KWH is a thousand watts for an hour of time.  So let’s see,  700watts/1000= 0.7Kw *720 hours/month = 504 kilowatt hours provided to these 70,000 homes.  So for your 504 KWH you have tied up 250USD with no profit for the company and non-union labor.

Congratulations are owed to Obama and the brilliant and esteemed Dr. Chu on your minimum of 0.75USD/KWH non-working solution to ‘green energy’.

Of course my numbers are generous to Obama and Chu.

THIS PATH DOES NOT WORK, IT IS NOT READY.  And anyone with a calculator can figure it out.  Yet so many celebrate this as progress.

Progressive in that it leads to economic destruction—yes, but progress? — not so much.


56 Responses to “Greenthink”

  1. mrpkw said

    But “renewable energy” is free if the government gives it to us !!

    Too many of the greenies don’t understand that without the government subsidies, renewable energy is worthless (as of now)
    Chuckle !!!

    Great post.

  2. mrpkw said

    Oh, and when you mention Dr. Chu, please point out that he is a Nobel prize winner.
    For some reason, Obama needs to always do that.

  3. Tim said

    Ironies abound. The ad I got is offering investment opportunities in green energy that provide 67% returns.

  4. Andrew said

    No one has ever made a solar panel more efficient than a leaf. Yes indeed Jeff, all our energy ultimately originates with the sun, and yet directly harnessing solar power is something that we have no idea how to do as well as nature has been doing for billions of years. You’d think that would be humbling, but not to “green energy” advocates. They think we can best billions of years of evolution to create a solar panel more efficient than a leaf-because if you think about it, that’s what would be necessary to beat fossil fuels, pretty much, since, well, that’s utlimately where they came from.

  5. Andrew said

    4-Clarifying my comment, “as efficient as a leaf” meaning, capable of taking as much energy from light as plants do, and turning it straight into electricity.

    The problem with leaves themselves are that they use they energy they collect to make glucose and to get some of it, you have to burn them.

  6. Steve Fitzpatrick said

    Jeff,

    Of course your analysis is right from an economic/technical POV. But I don’t think Mr. Obama and Dr. Chu care much about that. (Heck, if they did, they would be complaining about the terrible waste of money on corn ethanol, and they are not!) It is all technically stupid, but they are betting it is politically smart… and I certainly hope they are wrong about that.

    There is a case to be made for the need to reduce fossil fuel usage, in part to extend the available supply of fossil reserves (they are very valuable as chemical feed stocks you know) and in part to hedge our bets on the magnitude of future global warming. But there is NO case to be made for alternative energy absent some spectacular breakthrough in low cost electrical energy storage, which seems at best very unlikely.

    Real and immediate solutions to reducing fossil fuel use (if you believe, as I do, that this is needed) have to focus on promoting efficiency and on nuclear power, preferably fast breeders or perhaps thorium, if that technology gets up and running. In any case, substitution of alternatives for a large part of total energy is either a pipe dream, if it is only proposed, or an economic calamity, if it is forced on the public. Or to paraphrase Warren Buffet, alternative energy is a weapon of economic mass destruction.

  7. Andrew said

    The reason why ethanol will always get subsidized in America:

    http://en.wikipedia.org/wiki/Iowa_caucuses

  8. Brian H said

    Already there are graveyards in Australia of wind turbines that became instantly obsolete when the subsidies subsided. Sadly stupid, and stupidly sad, say I!

  9. Steve Fitzpatrick said

    Andrew,

    The most efficient solar cells are substantially more energy efficient than photosynthesis… but plants do some storage (biomass, sugars) in parallel with no investment required! Of course the most efficient solar cells are also the most expensive. But the real problem is not energy efficiency of solar, it is the cost of storage; storage is the Achilles heel of solar power. Thermal solar offers the possibility of storage as heat rather than electrochemical, but even there the cost looks astronomical for the average power delivered.

  10. Andrew said

    I stand corrected then. The problem is that we can’t store the energy as well, and still get it back out. Okay then, so we haven’t come up with a battery better than glucose but possible to extract energy from in a better way than burning it. That about right?

  11. Phillip Bratby said

    As you rightly point out, the two key factors are energy density and energy storage. Low energy density of solar and wind and lack of storage means they will always struggle to compete. Fossil fuels are essentially energy stores and reasonable energy demsity. But nuclear fuels (E=mc^2) are both high energy density and high energy stores, hence the future has to be nuclear fission and hopefully nuclear fusion.

  12. The problem with solar power is that the power goes off when the sun goes down. Which happens every day. Likewise wind power goes off when the wind stops blowing. I need my electricity to stay on all the time. When the juice goes out, my furnace stops working, and up here that means my pipes freeze within hours. Which means the electric company has to build and pay for enough real generators to carry all the load on a windless night.
    My outrageous electric bill goes mostly to pay off the mortgages on the electric company’s generators. The cost of fuel is minor compared to the cost of generators. Adding wind or solar doesn’t reduce the cost of generators, ’cause you have to have enough real generators to keep the customers lights on when wind and solar are not there. In short, pumping a little wind or solar electricity into the grid does nothing to reduce the customers electric bill, in fact it raises costs. You have the pay the wind and solar generators for their un needed juice, and you still have to pay off the real generator’s mortgages.
    If wind or solar really worked, zillions of people would install the equipment, just for the feeling of independence you get from not having to pay an electric bill every month.

  13. Gary said

    Energy density is the key needed to understand the issue, but it’s not true that “anybody with a calculator can figure it out.” By far, most people need simple pictures. Ross Perot was on to something with his charts and graphs.

  14. Frank K. said

    “If wind or solar really worked, zillions of people would install the equipment, just for the feeling of independence you get from not having to pay an electric bill every month.”

    You’ve hit the nail on the head. I’m all for newer, “cleaner” energy technologies, but let the free market sort out the winners and losers.

    BTW – pellet stoves are a *great* source of heat for those, like me, who live in colder climates.

    PS
    I think we should force GISS, NOAA, et al. to run their computer servers on solar and wind power, so as to force their model “results” to be “green”

  15. M. Simon said

    My favorite long shot for energy is Polywell Fusion. It doesn’t cost billions for reseach and a yes/no answer is expected in 2012 or sooner.

  16. timetochooseagain said

    11-Nuclear Power doesn’t even use a tenth of percent of the energy available from matter. If you want E=mc^2, you need a Matter-Anti-matter reactor, and those are science fiction.

  17. WxForecaster said

    Fitting that Doc-Zero has a posting today that parallels Jeff’s line of reasoning…
    http://www.doczero.org/2010/07/green-economics-and-the-void-of-desire/

    Another good past read — Understanding E=mc^2
    http://www.energytribune.com/articles.cfm?aid=2469

  18. “Newspeak”: Dr. Cho and the US Department of Energy

    1. A breeder reactor that uses neutron-capture on U-238 to make the more fissile Pu-239 is the closest thing to renewable energy.

    2. Dr. Cho and the US Department of Energy have carefully ignored nuclear rest mass data that shows neutron repulsion is the greatest known source of nuclear energy [“Attraction and repulsion of nucleons: Sources of stellar energy” Journal of Fusion Energy 19, 93-98 (2001); “Neutron repulsion confirmed as energy source”,
    Journal of Fusion Energy 20, 197-201 (2003)]

    http://www.springerlink.com/content/x1n87370x6685079/

    Neutron repulsion is the primary energy source for the Sun and the cosmos.

    With kind regards,
    Oliver K. Manuel

  19. Climategate exposed deep and systemic flaws that pervade the entire structure of publicly financed science.

    The most pressing issues now are correcting the corrupt system and ending the use of science as a tool of propaganda that threatens our form of government.

    With kind regards,
    Oliver K. Manuel

  20. Tom Fuller said

    Well, if you’re right, we’re in a heap of trouble. Fortunately (from my P.O.V.), I think you’re making some mistakes here.

    First, we are in a heap of trouble because in 50 years or so we’re going to need 3,000 quads a year of direct energy, as opposed to the 500 we used this year worldwide. I don’t think we want to burn that much coal, really.

    Second, renewables is more than just solar and wind, thankfully. 87% of electricity from renewables so far comes from hydroelectricity, which is set to double over the next 20 years. The other workhorse is combined heat and power, which is growing like crazy, especially in China. There’s also waste to energy, which has lots of room to grow.

    I sorta agree with you about biofuels, although I have faint hopes for genetic engineering coming up with something useful.

    I also sorta agree with you about wind, which peaked right about the time natural gas prices did.

    But I’m a big fan of solar power, and I think it’s going to be big. I think we will solve storage quite easily, with molten salt etc. The prices are still coming down, and they’ve identified process improvements for the next generation which brings PV to grid parity in most places.

    So, throw out wind and biofuels, keep pushing on hydro and CHP, invest a bit in waste to energy and bet on solar. And it works–the numbers add up, especially if we use some nuclear power and spend some time and effort on improving energy efficiency.

    We’ll get there…

  21. Jeff Id said

    “First, we are in a heap of trouble because in 50 years or so we’re going to need 3,000 quads a year of direct energy, as opposed to the 500 we used this year worldwide. I don’t think we want to burn that much coal, really.”

    Tom, I very much think production of this by coal could be beneficial. It will increase plant life and biodiversity while allowing time for people to find the next step. Not one single adverse effect of CO2 has been demonstrated to date and I’m someone who believes increased CO2 captures more heat. All of the damage is politically motivated conjecture.

    “combined heat and power”

    Is just an efficiency gain at greater cost. Running your own power plant costs more than running a centralized one and the ability to monitor the scrubbing of real pollution is lost because it’s distributed. Efficiency gain is not important if CO2 remains resident for 1000 years. If the IPCC is right and co2 stays resident for 1000 years, we can only eliminate all CO2 production, efficiency is moot.

    By the way, please don’t imagine that China’s combined heat and power is about efficiency. It’s about being insanely poor and finding that if you park the generator in the living room you get warmer.

    I understand that everyone prefers clean, but we’re pretty good at burning coal and gas cleanly in wealthy countries. It’s the third world which hasn’t worked it out. So again, I’m pretty sure that the only way’s you are going to get 3000 quads is through fossil and nuclear.

    “I sorta agree with you about biofuels”

    You know I like you, but ‘sorta’ agree means ‘sorta’ disagree, which means you don’t have the engineer which tells you the biofuel numbers are ‘complete BS’. It’s not a decision for us mere mortals. the numbers are not even in the ballpark and nowhere near reality, no matter which trick happens to be invented. Please read the numbers, you are too smart to let the BS rule your decisions. Biofuel is a joke far worse than Mann’s hockeystick rubbish. Yup I said it — worse.

    Wind may work when storage is invented so I may share less skepticism of this for the future.

    “I think we will solve storage quite easily”

    Nope, it’s very very difficult, not even slightly easy, not even remotely slightly easy, but it will be done because so many consumer products can be amazing with it. With or without green energy, if the god of physics has a solution, it will be found. The difference between us is that I see that time is the answer, government isn’t. My guess is that probably a hundred thousand scientists work on this every day.

    Hydro, first it’s fantastic by region, but the technology we have cannot even dent our requirement. I don’t even know why it’s discussed except to make people feel good. Geothermal is in a similar state but may have a better future.

    We have only one answer which will please those who feel CO2 is a problem — nuclear.

    Nothing else can come close.

    Unfortunately, we can’t put nuclear power in our cars, planes, trucks and trains. Because we don’t have storage… So we continue to burn fossil fuels at an ever increasing rate, the CO2 will increase in release rate and the only ones not using it will be those who feel they are doing harm.

    It’s not about what we want or think, I’ve studied energy production, thermal cycles, solar power, and efficiency in depth. We don’t get the choice, it is a very black and white decision with the grey potential for what may come.

    We simply do not have any technology to replace what we are doing for energy production today. The only things we can do are improve efficiency, switch to nuclear, or invest in technological development. The rest, like this solar project and investment in electric cars — is crap.

    If I’m making mistakes, it should be provable by numbers and if you follow tAV you know that I will admit my mistake.

  22. jcspe said

    Wind and solar sure sound good, but there are some really huge unresolved issues. What do we do with the excess power we don’t need at the moment it is converted? What do we do about the fact that neither wind nor solar is associated with a reliable and transportable fuel? Why are we so nonchalant about battery storage — why is everyone so convinced that producing massive amounts of lithium, etc. will not involve huge environmental issues and supply problems, too?

    So, actually the storage for excess solar and wind generation I am hoping for will be some sort of transportable fuel.

    I always liked the simplicity of the water-2-hydrogen/hyrodgen-2-water image, and darn that math exercise about the Carnot Cycle for making it fall apart right in front of my eyes. (The worst thing about thermo class was watching all my best self-delusions go straight to hell.)

    But anyway, a fuel such as hydrogen has a lot of the conveniences and practicalities of gasoline, if we can handle the corrosion problems. So, maybe the best way to store excess solar, wind, etc. power is not batteries — maybe the best way to store it is to use it produce some kind of fuel — and maybe that fuel is hydrogen.

    Then, when the wind is calm and the sun is down, the fuel converted with the help of recent excess power can be burned to bridge the gap. And, if we can create enough excess generation often enough, maybe we can produce suitable quantities of a convenient and transportable fuel to fulfill some of our other needs. Let’s face it, airplanes really shouldn’t be connected to the grid, and batteries are a pretty heavy thing to fly around. So, we will always live better if we can figure out a way to produce convenient and safe fuels.

    Although I thought of this myself, many others have too —

    “Economic Analysis of Hydrogen Production from Wind” —
    http://www.nrel.gov/docs/fy05osti/38210.pdf

  23. Jeff Id said

    There are some really cool hydrogen storage technologies coming, there are also good potentials (no pun🙂 with nanotube batteries.

  24. Tom Fuller said

    Hiya Jeff,

    Well, I’ll revise and extend my remarks to remove the ‘sorta’ when referring to current biofuels. They are not a solution to anything.

    As for storage, the famous line is that storage is available and easy to find–it’s just not cheap. But I do think it’s going to be solved in short order, because there’s a good financial incentive for doing so.

    Had we actually done any planning, we would have sited wind stations with an eye to using pumped hydro to balance the load–this is something that may happen going forward. It’ll be interesting to see what happens with CAES–compressed air energy storage. But I think the solar CSP plants are actually going to do it with molten salt first.

    Don’t underestimate hydro–it’s true it’s regional, but there are some pretty big regions where it’s applicable. Retrofitting existing plants can make a huge difference in electricity produced in the developed world, where we probably ain’t going to put up any more dams, but a ton of new dams are going up in the developing world.

    I agree with you about the need for nuclear. But 3,000 quads–that’s a lot of fossil fuels, Jeff.

  25. Kan said

    #22

    Hydrogen – “if we can handle the corrosion problems.”

    and the explosion problems🙂

  26. JT said

    If storage is the problem, are flywheels the solution?

  27. Cement a friend said

    Hi Jeff, as another engineer (chemical) I agree with you about so-called “green energy”. Another, word which makes no sense is “sustainability”.
    50 years ago the Club of Rome predicted the world would run out of all sorts of commodities. Everything depends on technological knowledge and on supply/demand which determines price and return on investment. The “greenies” who are mainly also socialists do not understand market economics. (I also have a MBA degree)
    The oceans have an endless supply of minerals. It has been economical to extract magnesium from seawater (although it is presently cheaper to use chinese magnesite deposits). Deuterium exists in oceans in endless quantities. It was already being extracted by the Germans in world war 11. With a little amount of research such as went into the US “man on the moon effort”, fusion reactors for electricity generation could be operating within thirty years. The money is available if politicians stopped subsiding green energy and sustainability politico-social research, and got rid of government public service hanger-ons.

  28. bob said

    I don’t believe we have an energy crisis. We are energy independent in the production of electric power, and substituting nuclear for coal will take care of any perceived problems with CO2.

    Hydroelectric depends on harnessing water power to turn generators and I have a hard time seeing the whacko-environmentalists allowing more lakes and dams. There are not only physical limits to hydroelectric, but there are political limits, too.

    As far as oil usage goes, the easiest solution is to drive our way out of the problem. Yeah, we will run out of easily available oil some day, but making oil rare and expensive is the key to finding competitive alternative energy to fuel our transportation. Of course we would still need petroleum to make the plastic for our garbage bags.

    Oil is not going away anytime soon, no matter how much money the government throws at research projects. Nothing will take the place of oil until we run out of the stuff.

  29. Russ said

    First there is no such thing as renewable energy.

    Jeff you got that right, it is the same as matter can not be destroyed or created.

  30. Ralph B said

    I guess it depends upon how you define renewable. I also say bio-fuel has its use in different niche’s. I can take the coconuts growing on my property and make bio-diesel cheaper than I can buy diesel. I pay for the methanol and caustic but it still works out cheaper than the pump. I also burn the waste in a boiler to run a uni-flow steam engine for electricity. The payback in dollars for that investment is a few years. The payback in satisfaction was immediate.

    So don’t say bio isn’t a solution to anything. The problem is bio doesn’t scale well.

  31. Ed Lambert, PE said

    Your “back of the envelope” calculations show a cost of roughly $0.50/KWH which is anywhere from 3 to 5 times what most of us pay for electricity now. That pretty much squares with what I have seen in electrical engineering academic studies. And, of course, your calculations do not begin to pay for the capital required.

    One responder talks about doubling hydro over the next years. My current graduate studies tell me that hydro is almost completely tapped out, at least in North America. Maybe he is talking worldwide; I’d be curious about that, if he cares to comment.

  32. j ferguson said

    Ralph B:

    Although i agree that biofuel doesn’t scale based on publicly reported experience, do you make this assertion based on your own experience? Are you really recognizing all your costs in your operations, your time, input value (cost of coconuts) etc?

    Starting with a “loverly bunch of coconuts” whose value isn’t imputed to your fuel costs might explain why biofuel production at larger scale wouldn’t make economic sense.

  33. Tom Fuller said

    Hi Mr. Lambert,

    Yes, the figures are international. There are 22 very large dams either under construction or in an advanced stage of preparation (code for they got the money to build the thing). One is in Russia. The others are in China, India, Brazil, Indonesia, etc.

    In addition, China is the world leader now in small hydro, as they are not staying awake nights worrying how to coax fish to swim up ladders.

    At some point the U.S. may actually wake up and realise that only 3% of our dams are used to generate power. At which point we may actually join the party. However, there is ample room for growth elsewhere.

  34. Tom Fuller said

    There was a guy named Otto bout a hundred years ago that built a car with a diesel engine that ran on peanut oil. Up until the 20s, just about everyone thought that some form of vegetable oil would be the liquid transportation fuel for the future.

  35. Bob said

    Jeff @ 21:

    1000 years residency for CO2? This article http://www.c3headlines.com/2009/12/human-co2-impact-on-temperatures-climate-the-ipcc-is-riding-the-wrong-forcing-horse.html says most peer-reviewed research indicates the hang-time for man-made CO2 is less than 10 years. And isn’t every CO2 molecule the same as every other CO2 molecule?

    Bob @ 28:

    At this point in time, I believe “whacko-environmentalist” is redundant.

  36. bob said

    Tom Fuller @33 said “At some point the U.S. may actually wake up and realise that only 3% of our dams are used to generate power.”

    Those are interesting numbers, Tom. Thanks.

    Does your source make any statement about the size of dam necessary to make electric generation economically feasible?

  37. David JP said

    I’ve asked this before, but this is the best thread to ask again.

    Can anyone comment on the physics of Lonni Johnson’s Thermo Electric Generator ideas?

    Some links (it’s been awhile since I’ve used the XHTML tags, so I hope these come through):

    http://spectrum.ieee.org/semiconductors/devices/super-soaker-inventor-invents-new-thermoelectric-generator

    http://www.rexresearch.com/johnsonjtec/johnson-th.htm

    http://www.popularmechanics.com/science/environment/green-energy/4243793

  38. jcspe said

    36.bob said
    July 10, 2010 at 3:03 pm

    Does your source make any statement about the size of dam necessary to make electric generation economically feasible?

    ++++++++++

    If I remember my fluids equations correctly, the big leverage in power generation using hydro is the head (elevation difference) between the top of the storage water and the tailwater of the turbines.

    In short, dam size isn’t really the question — dam height is the question. High dams take unique geologic and topographic conditions, and a lot of space to back up a pretty big lake.

    Hard to imagine too many opportunities for high dams in the plain states, but there is always a need for low dams for drinking water and irrigation needs.

  39. bob said

    Jpcse @ 38 : I well remember calculating head pressure, but I don’t think that can be the whole story. For example, a greater generating capacity will require a greater volume of water at a given head pressure to maintain the same Psi, but over a larger turbine blade area.

    I am so long out of engineering school I don’t remember all that went into the calculations, but, energy is energy and you don’t get the same energy flowing down a 12 inch pipe from 100 feet up as you would in a 36 inch pipe from the same elevation.

    The question I asked is probably more suited to a manufacturer of turbine generators. Well, Google, here I come.

    Thanks.

  40. bob said

    I am afraid Wikipedia has the story on hydro.

    http://en.wikipedia.org/wiki/Hydroelectricity

  41. Denis said

    We would do well to remember that the U.S. has gone done the bio energy track before. From the founding of the country through the Civil War period bio was the primary source of energy for transportation and industry. Wood powered trains, river boats, industrial powerhouses and home heating. The tiny population at the time was defolliating the land at a rate that, may I say, couldn’t be sustained. Much of westward expansion was driven more by the need for wood than land. Had bio been a sustainable source of energy the coal would have stayed in the ground. I don’t recall that Pres. Garfield earmarked $2 billion for developement of coal in Pennsilvania

  42. stupmy said

    Jeff, you might find it interesting to review the science on the origins of oil. Like *other* fields of sceince there is the concensus view that fossil fuels are organic in origin, but there are also new comers to the field that question the concensus (with compeling evidence). Having read a book on the subject by P. Ehrlich, the evidence for non-biological origin seems stronger. The theory being that fossil fuels are a by-product of tectonic process, which filter to the surface. Extremophiles in the crust feed of the hydrogen component, resulting in a biological signature at the surface. It all makes sense if you read up on it. Anyways, apart from being interesting, the point is that fossil fuels may well be “renewable” as its re-cycled material brought under the crust by tectonic movement constantly working its way back up, not the remains of old forests of limited amount. Worth considering!

  43. kim said

    So called ‘renewables’ all take energy from the natural climate regulating mechanisms of the earth, the sun, the wind, and the water. Because of efficiency losses, the value of the energy taken from those processes is always less than the value of the energy remaining within its climate regulating process. Who would bless such a rape of Gaia?
    =====================

  44. Geoff Sherrington said

    Meanwhile, in Oz, homeowners can get a $6,000 subsidy for putting a solar panel on the roof to make electricity. Yesterday, talk radio noted that many of the installations had not been connected from inverter back to grid, to feed any excess back. A government spokesman was reported as saying that this did not negate the grant.

    Am I right to suggest that solar panels take incoming heat of various wavelengths, then eventually re-radiate some heat back to space; but less than came in. If so, are they acting in parallel with the Greenhouse mechanism? It seems strange that the cure for greenhouse gases is machinery that does much the same demonised thing as GHG.

  45. DeWitt Payne said

    Re: Geoff Sherrington (Jul 11 21:28),

    It’s not exactly the same. Solar panels, by being efficient absorbers of solar radiation at short wavelengths, lower the albedo of the planet. Maybe not very much for a roof top panel on a roof that was already dark, however. Lowering the albedo would be equivalent to increasing TSI. But the albedo of the land surface is already pretty low, something like 0.08, so one would have to cover a substantial fraction of the Earth’s surface in areas of relatively high albedo to make much difference.

    I would prefer that they do not hook the inverters to the grid and force the power companies to buy power at retail, lowering the overall efficiency of fossil fuel use because base load power plants have to be throttled back and consequently raising rates for the rest of the customers. What would make more sense would be to require the purchase of a substantial battery system, like the ~50 kWh lithium ion system used in the Tesla roadster, to store power for use when the sun is down.

  46. […] by AJStrata at 8:18 am under All General Discussions Jeff Id at The Air Vent posted this excellent summary about energy sources and why the fossil and nuclear fuels work and the so-called renewables are too […]

  47. tarpon said

    Liberals have hijacked the language, there is no such thing as renewable energy, as you point out, physics says you cannot renew the burnt tree or renew the once used ethanol, or renew the energy contained in burnt coal.

    In fact all fossil fuels are just energy containers for carbon which then reacts with oxygen, by a process we call ‘burning’ which is really just an exothermic chemical reaction.

    What will people do when they figure out coal, a form of dense carbon, can be ‘refined’ into liquid transport fuels. In fact the UT completed a grant program from Canada after the first of 2010 to figure out what the cost would be … It was under $30 a barrel equivalent for oil. The process is called Fischer-Tropsch, invented in the 1920s, when oil was way too cheap to be economic. It was used extensibility by Germany in WWII, which has lots of coal, but no oil … History is your friend.

    And ethanol was discarded long ago as a substitute for gasoline, when oil was discovered. It’s ironic that Brazil after the discovery of massive oil deposits offshore were discovered. Why???

  48. tarpon said

    Aww crap, got interrupted, the last sentence should have read — It’s ironic that Brazil abandoned ethanol after the discovery of massive oil deposits offshore. Why????

  49. janama said

    Jeff – having lived on solar power for 5 years I found that solar is only giving the equivalent of full power for 6 hours per day, (9am – 3pm)= 1/4 of the day and that’s at latitude 28 – equivalent to Florida – higher latitudes will be even less.

  50. […] Deconstructing the notion of renewable energy, a must-read: Green energies such as wind, wave, solar electric, hydroelectric, and solar thermal, biofuel, etc. all have one thing in common.  They are all forms of solar power.  It takes energy from the sun to drive wind, wave and create plant fuels.  Another form of solar power is oil and coal, they are a form of very inefficiently stored solar energy from millions of years ago. Nuclear fission is also a form of solar if you take it back to the stars believed to have created the heavy elements used in the fission process.  However, both fossil fuels and Nuclear used energy from stars which has been stored in relatively convenient packages for release by the right equipment at a moments notice.  I call the other forms of energy stored solar, whereas instant solar, which is now being incorrectly called renewable energy, trickles in at a low density per unit area which requires the construction of massive area consuming collection zones. […]

  51. Chuckles said

    @47 Tarpon,

    Sasol have been turning coal and natural gas into fuel for more years than I can remember. There is no research required, it is a solved problem.

  52. Stan said

    Tidal power is not from solar power. It runs off of gravitation. We’re using the energy of the moon falling into the earth. Geothermal power is partly from heat stored from gravitation as well, in two guises – collapse of the dust cloud to make the earth directly generating heat, and collapse of the rotating dust cloud together with its rotational energy, which led to the earth spinning and some frictional forces in the interior generating heat as tidal friction slows the different layers differently. But it’s believed to be mostly radiative decay.

  53. Jeff Id said

    #52, I hadn’t even considered tidal power. Nice.

  54. DeWitt Payne said

    Re: tarpon (Jul 12 13:20),

    I see no evidence that Brazil has abandoned ethanol production. See here for example. Brazilian ethanol production is increasing at about 3%/year.

  55. Grunergy said

    Many companies are involved in this because of the profit surrounding the green movement.

  56. Once completed, we will not change our strategy to solar system accommodate a quick win.
    We now have six plants producing corn oil and that’s feed grade corn oil for all of 2012, have made wind farms an attractive form of solar system energy. Up and down the supply chain will receive additional economic benefits. The cost of militarily defending our access to oil alone could balance the budget! There needs to be made by rail.

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