A couple of weeks ago, I was contacted by a website called The Reef Tank about doing an interview with them on Energy and The Marine World. At first I said that this was a bit outside my expertise, but they said that was OK; I could just try to answer the questions to the best of my ability. We discussed my background and my interest in energy, this blog, climate change, and energy from the oceans.
They have asked me if I would mind linking to the interview so they might reach a scientifically-minded audience that is of a somewhat different cross-section than what they might normally reach. The interview is available at the link above. Below are excerpts:
Tell me about your interest in the potential of wave and tidal power.
I became interested in the topic several years ago. I was watching a story on the Panama Canal, and watched the level of a ship fall as the water in one of the locks was pumped down. I started thinking about the energy that could be extracted as that massive ship moved to a lower level. That led me to investigate wave power, which is similar in principle to the water rising and falling in a lock. Little did I know when I started investigating that a large body of work had already taken place in this area. Looking into waves naturally caused me to happen upon tidal power as well, and the enormous potential of the flow of the Gulf Stream. [RR: See this story that I did in early 2008: Infinite Underwater Energy.]
Tell me about your interest in ocean thermal energy conversion. How does it work?
I didn’t know too much about ocean thermal energy conversion (OTEC) until I was contacted last year by Bob Cohen, who is a friend of a friend and an advocate of OTEC. [RR: See Bob’s guest post here on OTEC: Ocean Thermal Energy Conversion.] The principle is pretty straightforward. Anywhere you have temperature differentials – such as a warm ocean surface and much colder layers deep down – you can use those differentials to extract work via a heat engine. You are essentially capturing some of the heat flow from the higher temperature reservoir to the lower.
I am sitting in Amsterdam’s Schiphol Airport right now, about to fly back to the U.S. When I get home, I am going to take my first real vacation with the family in a long time. I don’t expect to post anything or answer e-mails for the next week. Please keep the discussions civil, and if trolls show up just ignore them and I will deal with them when I can. Let me also take this opportunity to thank the readers and regular posters who make this effort worthwhile.
Aloha. 🙂
From the interview: “I accept the scientific consensus on global warming as a serious threat.”
Leaving aside the unfortunate fact that there is no such scientific concensus (How do you know there is a scientific concensus? Have you read every paper published?), it is hard to see how someone could drink the cool-aid on Anthropogenic Global Warming and then not be appalled by the idea of extracting energy from ocean thermal gradients.
Let’s get serious — if we extract a trivial amount of thermal energy from the oceans, then it is trivial and doesn’t matter. If we plan on extracting the energy equivalent of cubic miles of oil each year (which is what humanity needs), then we would be screwing big time with the oceans.
We would be heating the deep ocean and cooling surface waters — with currently unknown effects. We do know that ocean currents are driven by those temperature differences, and changes in ocean currents give us El Nino and maybe even ice ages. To say nothing of what it would do to the plankton that sit at the bottom of the marine food chain.
I am honestly astonished, Robert. OTEC is obejctively so much more dangerous than alleged Anthropogenic Global Warming that all serious people need to raise the warning flag at every opportunity. Lots of environmental research required before it can ever be considered.
Kin, I don’t think you understand what the term scientific consensus really means. You probably accept the scientific consensus on the theory of gravity even though you have never read all the papers and some scientists might disagree with it.
In a previous post Vinod Khosla said:
VK: “I have a paper on my website that postulates about a technology race between biofuels and batteries. Whichever one makes the most rapid progress will get the larger percentage of the total passenger miles driven in the world.”
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Recently, Andy Grove, co-founder of Intel suggested that Intel should go into the Lithium battery business. Apparently Andy Grove is betting on batteries amd not biofuels.
John
Bioelectricity Yields More Miles per Acre than Ethanol
It has been suggested before that it just might be more efficient to turn crops into electricity than biofuel, and here’s a study that proves that to be the case.
According to the study co-sponsored by the Carnegie Institution for Science, “Bioelectricity was the clear winner in the transportation-miles-per-acre comparison, regardless of whether the energy was produced from corn or from switchgrass, a cellulose-based energy crop. “
“The internal combustion engine just isn’t very efficient, especially when compared to electric vehicles,” says Elliott Campbell, lead author and professor at UC Merced. “Even the best ethanol-producing technologies with hybrid vehicles aren’t enough to overcome this.”
“Some approaches to bioenergy can make climate change worse, but other limited approaches can help fight climate change,” says Campbell. “For these beneficial approaches, we could do more to fight climate change by making electricity than making ethanol.”
The same amount of land required to make enough ethanol to propel a ethanol powered vehicle 8,000 miles will power an electric vehicle 15,000 miles. This is nearly twice as far if the biomass is burned to generate electricity rather than be used as a feedstock in an ethanol plant…..
John
http://electricaid.ning.com/profiles/blogs/report-shows-bioelectricity
I recently completed a Panama Canal cruise and have a clarification. The water is not PUMPED out of the locks. It is gravity drained down to the ocean, in some cases being passed through hydroelectric turbines to provide electricity for lock operations.
How can climate change be viewed as a serious threat?
Isn’t there scientific consensus that if not for climate change, large parts of Minnesota, Iowa, Wisconsin, Michigan, Indiana, Ohio, Ontario, New York State, and New England would still be under a mile-thick ice sheet.
I think most reasonable people would say that climate change over the last 12,000 years has actually been beneficial, or else none of us would be able to live north of what is now Kentucky, Arkansas, and Virginia.
John-
I have long said if we wanted biofuels, we should plant rapidly growing crops, then burn the crops to turn steam generators. I guess if somehow captured CO2 after burning (sequestration) then this would actually be CO2 negative.
Another added benefit would be cleaner urban air, as drivers used batteries and not ICEs.
I have to agree with Kinu that there is some disagreement, from serious people, about global warming. Unfortunately, the issue has become politicized. If you are a liberal, then you think GW is a problem, if you are conservative, you sneer at GW. That is about as far as most people get in their thinking.
However, paleoclimatologists will tell you we are in the era of Ice Ages, and only between Ice Ages now. Some speculate that the growing Himalayas are the reason for this Ice Age era. The high mountains capture rainwater and CO2, which is absorbed and locked into carbonate rocks. The increasingly lower global CO2 levels cause Ice Ages, by this theory. Of course, other factors play a role, such as the tilt of the earth and solar output.
I can say this: I do not want to live in an Ice Age, and neither do you.
It is certain the earth was warmer in the past than now, even the recent past such as 5000 years ago, and then 1000 years ago.
I would like to know if rising CO2 levels can avert another Ice Age. If so, we should praise rising CO2 levels. One more thing. When man first came to North America, the sea level was 60 meters lower (180 feet) than today. Man crossed the Bering Strait then, about 15,000 years ago.
Now Gore gets a wedgie over oceans rising two feet, and that’s a maybe. Surely, two feet will be disaster for seaside communities, but then a variation of two feet is nothing compared to what has happened in the past, even the relatively recent past.
Crud, for once I am going to have to agree with Kinu, except for his doubts about AGW.
What is needed is a system that would transfer the waste heat into outer space, so that you are countering AGW while generating power. Of course, easier said than done. But that should be the direction.
Yes, Virginia, AGW is basically a heat transfer problem.
Transferring heat from the surface of the ocean into the cold bottom (on a meaningful scale) is bound to unleash a multitude of unintended consequences.
CO2 was about six, or seven times as high as today at the end of the Carbonacious Period. So, what happened. We went into an Ice Age.
The Pacific is higher than the Atlantic. The Panama canal is filled with water from Gatun Lake.
Imagine a series of Huge Holes, containing massive, hollowed-out, steel plungers, raised with water piped in from the Pacific, and drained into the Atlantic.
Need more electricity? Dig another hole, and run another pipe. You could power the Western Hemisphere.
“Now Gore gets a wedgie over oceans rising two feet, and that’s a maybe. …but then a variation of two feet is nothing compared to what has happened in the past…”Anywhere you find sedimentary rocks (which is almost everywhere)is an an area that was once under water.
Most of Wyoming, Utah, and Montana was once submerged.
Had Al Gore been around 700 million years ago would he have been sounding the trumpet trying to stop the soon-to-be inundation of Wyoming?
I don’t think Al Gore has ever tried thinking of the problem on a geologic or astronomical time scale.
Benjamin said:
“I have to agree with Kinu that there is some disagreement, from serious people, about global warming.”
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I also agree with KINU.
To be honest with you, I wish Campbell had left all the carbon business out of his study and simply done an efficiency study.
Global Warming has become fashionable cause in academic circles and Campbell will no doubt get “brownie” points for including it in his study.
The Campbell study appears in the May 8 issue of “Science”
There is a fairly lengthy article about Campbell’s paper on the Green Car Congress website.
http://www.greencarcongress.com/
Yes, sea levels were lower in Paleo-Indian times long before any body ever heard of anthropogenic induced climate change.
John
“You probably accept the scientific consensus on the theory of gravity even though you have never read all the papers and some scientists might disagree with it.”
What scientific consensus on the theory of gravity? Really?
We are all reminded every day of observational evidence that unsupported things fall to earth.
Why that happens remains a subject of debate even today. Newton quantified the phenomenon, but did not explain why it happens. Einstein suggested that gravity was an effect of the curvature of space & time. Others think that again was a description of what happens rather than a explanation for why. Debate continues, informed by experimentation.
And everybody in the scientific community understands that any theory on gravitation will be discarded tomorrow if new observational data does not match the theory's predictions.
In contrast, no scientific mechanism for anthropogenic climate change has ever been presented — only CO2-mediated Anthropogenic Global Warming. The name was changed from global warming to climate change when the proponents (political activists, not scientists) decided to hedge their bets in the face of observational data that the planet is cooling. That is truly the reverse of real science.
But back to the Reef Tank — OTEC on a large scale clearly has the potential to have huge environmental impacts. What about wave power?
Interfaces are very important in biology. Waves crashing on beaches create important effects for the sea creatures, birds & mammals that evolved over millions of years to exploit the surf zone. Put in wave power generators, stop the crashing surf, and we threaten the environment.
Again, if it is done on a small scale, then the planet will be unaffected — and humans will get negligible amounts of energy. Do it on a large scale, and we are heading off into uncharted & potentially lethal territory. There would first need to be a major amount of research to prove that the damage caused by using wave power was within acceptable limits.
It is truly amazing how little the "green" energy crowd seem to care about the environment.
You don’t have to have oceans, and waves.
Think of Lake Mead. Imagine the U.S.S. Iowa sitting in the lake. Think about how much it weighs. Imagine that it was engineered so that when the water level drops a couple of feet the battleship presses down on a contraption to convert the kinetic energy into electricity.
How much electricity could you generate from the settling of a Battleship?
Anywhere you have a natural source of water flowing downhill you can have massive amounts of power generation.
No Dams needed.
This has been an interesting week
U.S. Sent $18.6 Billion Overseas and Imported 375 Million Barrels of Oil in April 2009
The US Gov planning to spend Billions on R&D and alternative energy.(hopefully some getting to good places)
US Gov cutting tax breaks to oil companies and reducing gov investment in hydrogen as an alt fuel.(I'm not sure if these are good steps or not )
Possible big strides toward cellulosic ethanol.
What Dartmouth was trying to achieve with CBP
http://engineering.dartmouth.edu/biomass/
What Mascoma (a Khosla Venture) with the help of many Dartmouth people in it's rank was able to achieve.
http://www.greencarcongress.com/2009/05/mascoma-20090508.html#more
It will be interesting to see where it all lands. There will be alot to talk about when RR gets back.
“Anywhere you have a natural source of water flowing downhill you can have massive amounts of power generation.”
Great idea! The bleeding edge of technology — about 127 years ago.
http://www.americaslibrary.gov/cgi-bin/page.cgi/jb/gilded/hydro_1
“On September 30, 1882, the world’s first hydroelectric power plant began operation on the Fox River in Appleton, Wisconsin.”
Most of the potential sources of falling water have now been tapped in the US. Provides most of what is reported as “renewable energy” — about 3% of total US energy use.
Hydro-power technology has spread around the world — Asswan Dam, Three Gorges, etc. When fully developed, hydro-electric power can probably supply a few percent of total world energy demand. Useful, but not the answer to our needs.
Modern environmentalists claim, with some justice, that hydro-power is not ‘green’ and maybe not even renewable. Certainly, since the dawn of the nuclear age, dam accidents have killed about 2 orders of magnitude more human beings than nuclear power plants.
What’s the next big thing? The sailing ship?
Read my previous posts. I’m not talking about “falling” water, or Dams.
In fact, you don’t really need “flowing” water. Think of “siphoning” gas. Suction. Vacuum. Whatever.
You can lift a battleship with a garden hose. All you have to do is utilize “suction”/vacuum/whatever in such a way as to use less energy filling the container than the very heavy floating weight (think, barge, piled high with sand) will produce when the water is drained.
Take 2:
Kinu writes:
I am honestly astonished, Robert. OTEC is obejctively so much more dangerous than alleged Anthropogenic Global Warming that all serious people need to raise the warning flag at every opportunity. Lots of environmental research required before it can ever be considered.Ah, you are one of the trolls Robert warned us about 😉
If you understood why GW is a real threat, you might understand why OTEC is completely different… but denial and understanding are incompatible. It’s pretty ironic getting lectures on the environment from GW deniers though, did you really think anyone is going to fall for that??
“If you understood why GW is a real threat, you might understand why OTEC is completely different…”
One of the principles which Robert Rapier has established here (which he meticulously maintains for his own comments except on this single subject) is — bring the facts to the table.
I have looked at the data on alleged Anthropogenic Global Warming. The data does not support the hypothesis.
For example, there is no correlation over geological time, historic time, or recent time between atmospheric CO2 and temperature. There is massive geological & historical evidence that the climate has always been continuously variable. The only "Climate Change Deniers" are the IPCC, with their now-debunked 'hockey stick' false claim of a thousand years of no natural climate change.
On this blog, we always start with the facts.
You make a flat assertion that “OTEC is completely different …”. But you did not bring any facts to the table; you did not support that assertion in your post. If there is a case to be made — make it! You might change some minds.
You have two choices, bc. Either post something explaining why massive changes to ocean thermal gradients are not a cause for serious environmental concern, or look in a mirror and study what a “troll” looks like.
“All you have to do is utilize “suction”/vacuum/whatever in such a way as to use less energy filling the container than the very heavy floating weight (think, barge, piled high with sand) will produce when the water is drained.”
Sorry, Rufus, I cannot follow what you are saying.
It sounds like you are talking about some kind of perpetual motion machine — use energy to fill a container with water somehow, and then let the water run out and recover more than the energy you put in? … let’s make that ???
By the way, don’t let your barge piled with sand confuse the picture in your mind of the underlying physical process. Archimedes — Eureka — floating body displaces its own weight in water. Ring any bells?
Well, we started off utilizing the difference in height between two bodies of water. No perpetual motion machine, there.
Then, we moved on to taking advantage of the obvious differences in height between two points in a “flowing” river (not by damming it up.) No perpetual motion, there.
Then, I supposed that you might even be able to take advantage of another natural phenomenon, the siphoning effect (or, whatever the scientific term would be) to fill my container using less energy than I would generate with my settling barge (plunger, whatever.) THIS might be getting perilously close to a “perpetual motion machine. I’m not a Hydrologist; I don’t know.
Anyhoo, I’m quite sure those people in Panama could generate a Lot of electricity if they put their natural Geography to work.
One of the principles which Robert Rapier has established here (which he meticulously maintains for his own comments except on this single subject) is — bring the facts to the table.I am going to come off of vacation to just address this, because I don’t agree. I am not trying to argue a point here. I have said that I think global warming is real, and that humans are contributing. But I am not trying to argue with or convince anyone that this is the case. I am stating my opinion. If I was trying to convince, the burden would be different and I would indeed be expected to bring facts to the table. As I have stated before, I think the subject is complicated enough that I can’t devote enough time to do it justice. And I think you would even agree that there is a lot of material to sift through and interpret.
I understand your point about OTEC; we are again doing something that potentially changes the environment with unpredictable consequences. The question is, “Are you doing a little or a lot?” A little of something – as you say a trivial amount – won’t matter. The problem is that it isn’t immediately obvious to me that what we are doing to the atmosphere is trivial.
I was afraid to go off and leave this thread, because I was afraid it would end up being just a debate on global warming. I actually said that to Ava at The Reef Tank when she asked me to post the essay that I would probably get dragged into a debate on global warming that I am not really interested in getting involved with.
OK, back to vacation. Sitting on my balcony in Hawaii, with a good view of the ocean.
RR
Robert — Agreed, this thread should not be about alleged Anthropogenic Global Warming.
And fundamentally, it is not. It is about the environmentally-dangerous alternative energies you discussed with the Reef Tank.
The only point was the startling contrast between your willingness to accept concerns about alleged Anthropogenic Global Warming and your total lack of comment about the environmental hazards created by those ocean-interfering processes. Those processes, on a large scale, would seem to carry much greater risks to the environment than a small increase in the atmospheric concentration of one of the much less significant radiatively active gases.
Enjoy your vacation!
I am with RR. I would rather debate reducing the environmental impact of producing energy. While CO2 emissions may be one of the easiest parameters to keep track of on a life cycle basis. However, AGW is the least significant of a long list of potential environmental impacts.
Ocean energy demonstrates the endless fascination with bad ways to make electricity. If it does not work very well, it is not going to have any potential to reduce ghg emissions from coal plants.
While I am all for R&D to try to make the impractical work, something has no potential will not solve a problem.
Then there is the false logic. For example,
“Bioelectricity Yields More Miles per Acre than Ethanol”
Biomass is a good way to make electricity at a reasonable cost. It is about 3-5% of generation and could be higher. Depending on how it is done, biomass could have significantly less ghg emissions.
However, it is a giant leap of logic to suggest that BEV would get their electricity from biomass. The use of electricity is independent from the generation except under very rare circumstances.
Second BEV is another example of the endless fascination with what does is not practical. The only reason BEV are nothing more than a curiosity is that the ICE is so overwhelming more practical.
Simply put efficiency does not matter if it does not work. Comparing what works to what is impractical is pretty much a waste of time unless you have a really good plant to make the impractical very practical.
Kit P said……
“However, it is a giant leap of logic to suggest that BEV would get their electricity from biomass. The use of electricity is independent from the generation except under very rare circumstances.”
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In a graphic from his paper Campbell shows the power generated from the bio-fuel plant is sent directly to the grid.
Electric vehicles are then charged at home, at public charging stations, at work, etc.
This graphic can be viewed at the ElectricAid blog-site from an entry entitled:
Bioelectricity Yields More Miles per Acre than Ethanol
http://electricaid.ning.com/profiles/blogs/report-shows-bioelectricity
Click to enlarge the graphic which is taken directly from Campbell’s paper.
The electricity from the bio-mass plant is fed directly into the grid.
John
Kit P said….
“Biomass is a good way to make electricity at a reasonable cost. It is about 3-5% of generation and could be higher. Depending on how it is done, biomass could have significantly less ghg emissions.”
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Here is an interesting film on how the German’s plan to integrate re-newables such as Wind and Solar into their electrical grid.
Part of their strategy is to use biomass to produce bio-gas which is stored in tanks to fire gas turbines which will level out fluctuations from wind and solar,
Excess wind capacity is stored utilizing pumped hydro. Some hydro plants can be brought on line in less than 60 seconds.
Pumped hydro resources also can be used for peak shaving like the bio-gas plants.
The German “Smart Grid” allows rapid switching of all resources “at the click of a mouse” as the film states.
The Germans plan to be at 40% re-newables by 2020. Here’s how they plan to do it:
The Combined Power Plant
If you would like to watch a You Tube film explaining all this, you will have to type in the words “The Combined Power Plant” into the You Tube search box.
Easy to understand and interesting seven minute film.
John
The Germans have been working on that Biogas thing for awhile now. You know they don’t relish being dependent on Russia for their natural gas.
“The electricity from the bio-mass plant is fed directly into the grid.”
That is correct but what is your point?
“Part of their strategy is to use biomass to produce bio-gas which is stored in tanks to fire gas turbines which will level out fluctuations from wind and solar.”
The first thing I do with a German AD plant is get rid of biogas storage because it results in a better IRR on a business plan. German engineers do not understand the KISS principle (keep it simple stupid.)
Without sounding too harsh, Germany is a small country in Europe. There are some thing they do well. My company manufactures renewable energy equipment in Germany. We also have created a joint venture to build biomass plants in the US. I work in power plant R&D.
Having said that it is important to understand that Germany is not the US. It is also important to understand the difference between a fantasy and practical.
Here is some real time wind information:
http://www.midwestiso.org/page/Total+Wind+Generation
“Then, I supposed that you might even be able to take advantage of another natural phenomenon, the siphoning effect (or, whatever the scientific term would be) to fill my container using less energy than I would generate with my settling barge (plunger, whatever.) THIS might be getting perilously close to a “perpetual motion machine. I’m not a Hydrologist; I don’t know.”It won’t work Rufus. The siphon effect doesn’t provide any free energy. And it won’t push water uphill. Or at least, it will temporarily, but your ultimate sink must be lower than your source. I gather that maybe you were talking about siphoning water from the Pacific to the Atlantic via Panama, but that’s not going to work either. You see, the siphon effect is nothing more than air pressure acting on the surface of the source. Atmospheric pressure at sea level is equal to a column of about 30 feet of water. You can’t siphon water over a hump higher than 30 feet — in a rigid sealed siphon tube you’ll just form a vacuum. So those mountains in the middle of Panama will cause you big problems.
You would need to cut an actual trench from the Pacific to the Atlantic, and even then the mean sea level is only 20 cm difference so the energy density would be pretty low. You are more likely to be able to take advantage of a large tidal bore to generate energy, since tides on opposite sides of Panama have opposite phases. But you can do that in any place with suitable geography — see the proposed Severn Tidal Barrage for example — huge engineering projects to be sure, but perhaps easier than mowing a trench through Panama.
Nice idea while it lasted though. 🙂
Thanks a lot, Pete. I figured Someone who knew what he was talking about would show up.
We’ll just “run a pipe” through the mountains. 🙂
The difference is only 20 cms? Dang, I thought it was greater than that. Hmm.
Next.
Kit said:
“The first thing I do with a German AD plant is get rid of biogas storage because it results in a better IRR on a business plan. German engineers do not understand the KISS principle (keep it simple stupid.)”
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Kit,
I think the reason the Germans are storing the bio-gas from the digester in tanks is because they are using their bio-gas generating plants to provide electricity only in times peak load and for buffering .
As I understand it, (from the film), the gas fired turbines sit idle part of the time just like natural gas fired turbines sit idle and are only fired up when base line plants can’t carry the load.
In the film the bio-gas fired turbines are not used to provide base load electricity. They are only firing them up at times of peak load and for buffering.
That’s the reason for the storage tanks. Since there is no need for a continuous supply of bio-gas, the surplus output from the digester is stored in tanks.
John
John, you do not know why the Germans do things a certain way and I do not care.
I really do not care to spend much time studying any loony ideas from places like California and Germany. I spend time learning about good plans developed by utilities for resource planing.
“As I understand it, (from the film), the gas fired turbines sit idle part of the time just like natural gas fired turbines sit idle …”
John, they are not the same. The devil is in the detail. NG peaking plants are cheap to build and expensive to run. Very expensive when natural gas prices are high.
General renewable energy and nukes are expensive to build and cheap to run. Therefore you want to maximize the capacity factor and the longevity of this type of generation.
Therefore, what is done is that wind and solar offset NG peaking plants.
The other concept that John is missing is scale. John, did you look at the link I provided? Here is a source of real time info not junk science found on youtube. Notice that wind generation drops by 2000-3000 MWe over the coarse of a day. A large AD might be 1 MWe. That means you need 2000 sour gas compressors and 2000 storage tanks.
Rather than invest sour gas compressors and storage tanks, put that money in a larger engine and generator. Most places with agricultural biomass also have diesel or propane fuel storage. If you have biogas for a 1 MWe genset, buy a 2 MWe genset and increase the peak power with propane if needed.
Speaking of scale, I think it was being ignored here earlier when it was suggested we might need to sound the environmental alarms over OTEC. The Gulf Stream alone transports 1.4 petawatts (= million gigawatts). And that is only a fraction of the thermal energy in tropical waters. Suggesting that human scale energy extraction could alter the climate is like saying that installing wind turbines will make the wind stop blowing.
Rufus:
The world is just a few years away froma global NG glut. LNG tankers and port facilities are being built worldwide, while sale gas promises to make gas plentiful for the next 120 years.
The doomsters never talk about NG.
Game over. No doom. We have NG coming out of our rear ends for generations.
Germany won;t need Russky gas. Biogas may work, but NG will be cheap-cheap.
Heck, Benjamin, I hope you’re right.
If you listen, closely, you’ll notice the only thing I’m really, really against is shipping all of our money to the middle east (or, running out of energy.)
Mention of biomass got me to look at the EIA data. Biomass accounted for about 1.3% of the electricity generated in the US in 2007. Weird, I thought it was higher than that. I wonder why it’s not higher.
http://www.eia.doe.gov/cneaf/alternate/page/renew_energy_consump/table3.html
Benjamin,
From:
Energy Information Administration
(Official Energy Statistics from the U.S. Government)
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Total U.S. proved natural gas reserves – resources that have been identified and tested and either have been or will be developed – have increased for the last eight years, and in 10 of the last 11 years. Recent drilling trends indicate continued growth, with a stronger concentration on unconventional resources like shales. Shale formations in the lower 48 States are widely distributed, large, and contain huge resources of natural gas. They are just starting their full development. Already, the production from just one Barnett Shale field in Texas contributes more than 6% of production from the lower 48 States, which is more than from the large producing State of Louisiana.
http://tonto.eia.doe.gov/energy_in_brief/natural_gas_production.cfm
John
“Suggesting that human scale energy extraction could alter the climate is like saying that installing wind turbines will make the wind stop blowing.”
Or maybe like suggesting that a trivial increase in a minor radiatively active gas will turn Planet Earth into an oven?
Remember that Ocean Thermal Energy Conversion will be very, very inefficient — an inevitable consequence of straightforward thermodynamics. There is a low temperature differential between the hot & cold ends of the system, which means most of the heat transferred is going to be pumped out as waste (or rejected) heat.
Take the ~15 TW that humans use now around the planet, increase that by a factor of 3 or 4 to account for increased energy use as developing countries develop European-sized energy appetites, and multiply that by a conversion efficiency of just a few percent — and we would be messing with heat transfer in the ocean big time.
The reality, Pete, is that neither you nor I nor anyone else knows just how much energy we can extract from the oceans before we start running into consequences. All I am saying is that the research on that needs to be done before anyone gets excited about OTEC.
Isn't the Precautionary Principle great?
Points taken, Kinuachdrach, but I don’t think it’s realistic to think that OTEC could ever provide all of humanity’s current energy needs let alone multiples of it. For a start it’s only available within maybe 20 degrees of the equator, so barring big surprises like a global hydrogen economy OTEC energy is not going to get shipped around the world. I’d see it more as one of many renewables in a diverse mix, perhaps particularly suited to arid locations where the freshwater byproduct would be important. We could worry about possible climate change effects after OTEC is generating in the terawatt range (unlikely any time soon, or probably ever).
I DO think, on the other hand, that CO2 is more of a worry — the evidence is suggestive if not compelling. I happen to disagree with the standard line on emission reductions though. We don’t know how big the anthropogenic component is, how big the effect is going to be, and whether we could do anything about it even if we tried. I say save the money for mitigation when we know what’s needed — flood defences etc., and ultimately moving cities and populations.