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When it comes to renewables ligno-cellulose is going to be big. The Americans are investing a huge amount in to this area when it comes to gene engineering to get more energy out for less inputs.


Corn traditionally has a I/O ratio of about 1:2. GEN's salix project when used with geothermal energy comes in at about 1:16.


The apparently sold it, but I know there is a planned IPO soon of a company for about $100m. The purpose of which is to build a geothermal plant to produce biofuel. I guess it is the same one as GEN had since the last I heard they had to trial a pilot plant first to see if it was commercially viable.



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hi plastic


A couple of things regarding the cellulose idea which confuse me. First off, it is a nice idea but it is simply not an economic proposition. I see recent research suggests that every gallon - 2.2 litres - of the stuff produced in the US costs those taxpayers about US$3. That is even more costly than the stuff made from corn.




The second worry I have is that it is not as if we have endless supplies of unwanted cellulose. My meagre knowledge is that supplies would come from crop stubble, timber, specially grown crops or recycled rubbish. Modern farming effectively mines the soil, taking out far more than is put in, and the only way around that is through throwing mountains of fertiliser and lakes of irrigation water back onto farmland. I'm not saying that industrial farming is not sustainable but I do think that already we are struggling to keep up supplies of food so the idea that we can also produce huge supplies of energy from arable land is for me a stretch. For instance something like a third of corn produced in the US is already used to produce energy but that energy contributes less than 5% of US energy requirements. Also I suspect that standing timber has much greater value and is more sustainable than harvested timber.


Anyway I could be all wrong here: I have no confidence in myself to see a passage through. And it is not as if being reliant on government subsidies to survive necesarily means that an industry cannot hang around. For instance check out that graphic from Barry Ritholtz's blog. Clearly the business interests behind fossil fuel benefit hugely from government largesse. But there is little reason to see why the fossil fuel sector would be replaced by the cellulose sector as such a change would be merely replacing one snout for another at the trough.




Personally I think some of the photovaltaic technologies and some of the geothermal techologies, which offer at least the promise of price competitive energy, may eventually win out (that is if the forces of evil such as the coal lobby in Australia, which own "leaders" such as Greg Combet and Martin Ferguson, do not succeed in distorting the playing field).


On another note, I see Pres Obama appears to be going for the short term fix of jobs creation over the long term solution of technology development. This last week he opened a new lithium battery factory, designed to supply product for Ford and GM's hybrid cars. The point is that the company behind the factory is Korean. Korean companies spend massive amounts of money on research and development - 5 or 6 times what Australian firms do (from memory) - and my guess is that they are commercialising Korean, not American, research. Anyway better than nothing.



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Sorry to be late joining in with this, but I am a little puzzled...


The title of the thread is "Renewable energy" then goes on to include geothermal, etc.


First - geothermal isn't strictly speaking "renewable" - it is replenishable but it has a finite lifespan - until the planet dies basically, or until the particular holes go cold. But it is not renewable.


All talk of "renewable energy" seems to forget one of the most basic laws of physics - energy can't be created or destroyed, it can only be altered from one type of energy to another. It's called the Law of Conservation of Energy....


So, when I take that into account, I look at all the options proposed so far. I see corn being grown to burn as fuel via ethanol, instead of feeding starving people. I see wind being proposed - but have you ever stood close to one of those windmills, let alone an entire landscape full of them?


All options are worthy of discussion, of course, and wave power seems to me to be the most "replenishable" in terms of supply of energy and efficiency of conversion.


But one option stands out from ALL others, in terms of energy produced per unit mass of fuel, and that is, of course, nuclear. With the current 3rd generation technology, and with recycling of the primary waste for another round of power generation, to produce secondary waste that is no more radioactive than the original uranium was, I think the technology has LONG ago passed the point where emotional fear should be well and truly laid to rest. It's like an irrational fear of flying, or even going on a boat. Most people don't even give it a second thought these days - you are, in fact, safer in a plane at 35,000 ft than you are on the ground driving a car or riding a good healthy bicycle.


And so it is, or should be, with nuclear power. More coal miners die in China alone each year than have ever been killed by nuclear accidents. I'm not counting Hiroshima or Nagasaki as accidents there....


It is no coincidence that China, India, France, even the USA, along with many other countries, are now seeing the obvious and progressing down the nuclear power pathway. Australia needs to get its emotional head out of its emotional ass and discuss the option like adults with some common sense.


When was the last time you heard of anyone coming to harm on a nuclear powered ship? Those smaller self-contained generators could power a community. One buried close to a development could power it for years, only requiring fuel replacement every few years. Self-contained, buried in concrete with secure access - ideal.


And of course the kicker is that a side product of nuclear power plants is hydrogen - which will almost certainly be the fuel of the future for vehicles once the oil runs out. Hydrogen fuel cells, producing nothing more than water vapour when the hydrogen is sparked with oxygen, are already available in California, with hydrogen pumps at many service stations. The only vehicle commonly available over there at the moment is the Honda Clarify (see http://automobiles.honda.com/fcx-clarity/ )


That is where the future lies - nuclear power for electricity, and hydrogen fuel cells for vehicles.

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:sadsmiley02: Hi NS,

You're making some valid points about "renewablility" - especially of corn and other foodstuffs that would indeed be put to better use feeding people than burning up; I'd much rather limit the conversion into fuel to unpalatable waste, like hay, banana fibre, etc.


I also agree about the noise that wind turbines make - but fail to see that as a problem when nobody is near enough to hear it.


Geothermal energy may indeed be exhausted at some stage - when the world gets cold; but I can't see a reason why anybody should worry that far out. (Read Isaac Asimov's "The Gods Themselves")


But one category seems to be missing in your list of suggestions: Solar Energy. That is indeed plentiful, may last even longer than geothermal, i.e. will certainly outlast humanity, and only a very small acreage will suffice to feed the global demand.


Instead (?) you seem to think uranium is renewable. How do you figure that? I'm still under the impression that so many tons of U3O8 are used up when heat is created - most of which is going to waste, but that's efficiency: yet another different story.

Like you, I'm scientist enough to know that most of the fear is irrational and N-plants can be made virtually fail-safe. I'm also statistician enough to know that no matter how fail-safe you engineer something, there is always a residual, non-zero probability of something failing. MTBF (Mean Time Between Failures) of 10,000 years may sound impressive - right? But multiply that by 10,000 N-reactors, and you get one "incident" per year. Hopefully, the effects of those incidents will remain confined to a narrow local area rather than spread a cloud over an entire continent. To those affected, one Chernobyl incident lasts a lifetime...

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Triage, I know of one project utilizing biomass crop and geothermal energy that gives I/O ratios of about 1:16 with very valuable by-products making it fully economical.


The secret?


Genetic engineering. Under the old paradigm with oil at $30-60 it is un-economic. Now with production possibility frontiers being expanded through GE and more advanced soil management techniques it is fully economical. The extra benefit is that previously unproductive marginal land can now be utilized and made more valuable.

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Hi Arty :) Good discussion.


you seem to think uranium is renewable


Nope - never said that at all. I didn't think I was implying it either. But uranium generates more power per unit mass than any other power source. WAY more than coal, or gas, or oil, or.... whatever.


Nuclear power needs so little fuel, that the actual RUNNING costs of a nuclear power plant are negligible. Not like coal power stations, for example, where the cost of coal is the major factor.


I agree that solar energy is plentiful, but the efficiency of conversion (or lack of it) is the problem. I'm not sure that I agree with you that only a few acres of solar panels would provide the world's power needs..! The solar panels on my neighbour's roof generate ALMOST enough to run their house, but they are not particularly energy-hungry (they only have one computer, for crying out loud... ;) )

In fact, a couple of months ago, they actually put a little bit of power back into the grid, then got a cheque from Ergon, and promptly had their pension adjusted downwards due to the income! Go figure.


Solar may be one answer in a few generations time, if the efficiency of the photovoltaic conversion is improved. But at the moment, I don't think it is a serious contender for baseload provision for cities, industrial complexes, etc etc. And the storage of solar power by the solar/thermal installations is a bit more efficient, but still has a long way to go.


Nuclear power is here, right now (France has had over 80% of its power by nuclear since 1978), is extremely efficient in terms of power per unit mass, is safe, is cheap to run (but expensive to build), and is inevitable (a big claim, I know). Most of the world is heading that way, as the oil runs out, and as coal is seen by more as a very dirty power source as well as very inefficient in terms of power per unit mass.


I think it will be nuclear power, or sit freezing in the dark. And the sooner Australia has this discussion sensibly and unemotionally, the better off we'll all be, not to mention the vastly-reduced carbon footprint of our country.


But, as always, I remain open to discussion, suggestions, arguments, and new ideas... :)

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hi NS


If I may butt in :)


Nuclear power is here, right now ...


Whilst it is true that there already exists nuclear power plants it is not true for Australia that nuclear power is here, right now. To get a nuclear power station operating from scratch takes well over a decade. The link below gives the time as a minimum of 15 years. Reality is that we are blessed with the most gutless bunch of self-serving short-sighted mean-spirited politicans who live by whatever the latest polls are saying. Name me one politician, after what happened to Turnbull and Rudd, who would risk prosecuting the case for a nuclear power plant in a specific location when there will be no obvious benefits for at least 5 election cycles (in other words the decision would require the current crop of politicans to wear the mother of all scare campaigns for the benefit of a future generation of politicans - mate it simply cannot happen given the way things currently are in Oz). It may well be different in NZ - you're a kiwi, yes? - because as much as I like the occasional win against NZ in footy I have to tilt my hat to the kiwi political process for regularly making the brave decisions that Aussies do not have the gonads for.




Also it is my understanding that no-one has really solved the issue of what to do with the waste products from nuclear power plants. I'm not saying that this is not solvable, merely that at this point in time no-one has come up with an acceptable long-term solution.

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Triage - first, to put paid to the ultimate insult (just kidding ;) ) - I'm not a Kiwi...! I'm in Brisbane and a Pommy-born Australian citizen.


The thing with the waste is that everyone forgets about the tens of thousands of drums of radioactive waste sitting under every hospital's radiology department around the place. The latest generation of nuclear power plants, including the so-called pebble bed reactors, can recycle the primary waste for more energy, producing secondary waste which is not much more radioactive than the uranium was before it was pulled out of the ground. So just bury it again...!


The reason that the primary waste is so radioactive is BECAUSE it still has a lot of unreleased energy in it - and the newer reactors can take advantage of that to use the energy, thus rendering the waste much less active. South Africa is a leader in this technology, I believe.


Of course you're right about the gutless wonders we elect to parliament, plus the phenomenon of NIMBY (Not In My Back Yard) which is so prevalent in Australia. However - in France nobody seems unduly bothered by living down the road from a nuclear power station - the only effluent is water vapour (you know - all those cooling towers that they always show as stock footage when any discussion of global warming is on the TV - but it's only steam).


Also, in Australia we are blessed with so much wide open space, that the power plants don't have to be in ANYONE's back yard. As long as they are within reach of the grid, they can be anywhere. Preferably somewhere near the coast for cooling water supply (and they can also double up as great desalinators as well as providing hydrogen for the next generation of vehicles).


If the USA, UK, and much of Europe can proceed down the nuclear power pathway, with the much higher population density, then surely Australia can do the same thing without upsetting anybody?


But there are too many people who don't want a rational discussion, or who live and die by polls for short term popularity and votes.

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Hi NS,


Good discussion indeed :)

a couple of months ago, they actually put a little bit of power back into the grid, then got a cheque from Ergon, and promptly had their pension adjusted downwards due to the income! Go figure.

Yes, we received a similar note the other day - but in WA, the rebate for any power we feed back into the grid is the normal rate, even minus GST. And as we have at least 2 computers and 3 monitors running, our 1KW system doesn't generate much excess. We'll soon be ramping it up to 2KW; planned it that way from the initial installation, when we opted for an inverter with spare capacity.


When I used the term "acreage", I didn't mean to imply "a few acres" - in fact, I've read somewhere it's an area the size of Tasmania (from memory) spread strategically around the globe. Efficiency will indeed have to improve, but there too, I'm more optimistic and don't believe it's going to be take "generations". There are even a variety of technologies to choose from, some of which have been described in a recent edition of National Geographic:



One huge advantage I see solar having over nuclear (and coal, oil, gas...) lies in the "cooling effect" inherent in the technology. By that I mean: Traditional power plants use fuels to heat a liquid in massive boilers, which essentially drive a steam engine/ turbine, the motion of which rotates a generator. Regardless of claimed efficiency, there is always an excess of process heat that raises the ambient temperature of the surrounding environment; in other words: it contributes to the global warming.

In contrast, when solar energy is converted - either by photo-voltaic or heating processes - the energy syphoned off to produce power reduces the thermal effect that the Sun's rays would otherwise have.


Agreed, solar power is not much good at night; but even on that front, long-life "battery systems" are being developed. Some of those are also mentioned in the NG article: hydrolysis and thermal storage in salts are just two promising methods.

And another example comes to mind: When I was a kid, a huge water storage system was built near my home town. During times of excess power production, water from a nearby river would be pumped up into a giant reservoir on top of a nearby escarpment. During peak demand, it would be released to drive turbines for increased production.


While not every technology suits every condition, I'm sure that thinking outside the squares of traditional "one-size-fits-all" designs can make a huge difference. We have to "want it" and force our politicians to create an enabling framework.

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