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Thread: energy sources
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23rd July 2011, 09:59 PM #76Intermediate Member
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Cheap Solar Water Heater
Hey artme,
I agree - solar is really good for heating water. Yes, there are a few variations - each with some pros and cons.
If you are going to make it yourself (and why not) then I think the cheapest is neither of your suggestions.
You can make a water heater from the black flat tubing used for swimming pool heating for around half what you will spend on other methods - you have seen this stuff spread on a roof ?
People will tell you it’s not efficient - and they’re right.
But if it’s a couple of percent less efficient - and 50% of the cost - then you are ahead, aren’t you ?
Let me know if you are interested.
Cheers,
Bob
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23rd July 2011, 11:36 PM #77
Lots of bits and pieces so I'll do this manually:
woodbe:
I linked a company...
Yes I know, but the technology is well understood. Until I see some spectacular breakthrough which does not involve magic centralised solar thermal isn't practical.
What it lacks is scale and effective efficiency monitoring and remediation that a large scale plant would bring with it.
Yes great point. Only issues is that like an inefficient water heater or pool pump it's in the householders interest when it starts costing them to get it fixed.
Interesting that you can put a gas fired electricity plant in your backyard that is more efficient than Yallourn! Any idea what they cost?
There isn't really any fire, it's an electrochemical reaction, although I suppose it gets oxidised so I guess it's burning of a sort. They predicted once the factory was in full swing about $10k which isn't much more than a 1.5 PV system withouth the rebates. And of course bluegen generates 24/7
citybook:
Absolutely no good hoping for the coal industry to change
It is not the responsibility of the coal industry to develop renewables. It is their responsibility to obey laws set down by our democratically elected government and to make money for shareholders. If you don't like what they do (and I often don't like what corporations do) they should not be the target of your protest, unless they break the law. If the law fails it is the fault of the law makers, enforcers and the people who voted them there...Like the great way the qld government is handling coal seam gas mining.
When you say renewables aren't competitive at $23 a ton, I don't think many energy sources can run at that price. The $23 looks like the carbon tax ? The coal price is closer to $123 a tonne - maybe we are going to have to pay at least that for any sort of fuel into the future.
The $23/ton carbon tax is meant to make coal dearer in order to encourage investment by private companies in other methods, and is a tax collected by the government to pork barrel, er I mean compensate working families, and for the government to use to pick losers, er I mean winners in emerging technologies, and provide a slush fund to give cushy high paid jobs to labour mates, er I mean outstanding executives. Don't get me started on the schemes flaws or I'm likely to go all "global warming is a scam" on you...
By the way the expensive coal they talk about on TV etc is coking coal, for making steel. Steaming coal is the mud no one else wants. Ask me about coal, just ask me. I spent about a decade testing the stuff, I can put you into a coma blathering on about seams and layers and coking properties..
It's black and it'll get you dirty from 30 feet.
Bushmiller:
I would love you to be right but.... From Wikepedia. Produced 65% of input power for 0.5 secsonds.
Wikipedia isn't always right. I can't remember if it was jet or the japanese one but they sustained positive output for a couple of seconds. I've been fascinated by fusion since the 80's when I was lucky enough to attend a seminar by one of the principle researchers at JET. Made what I was doing seem pretty trivial.
Ah there you go I see you've a quote about JET. I'm pretty sure it's wrong.
About the Bluegen fuelcell - I believe it is a combination high temperature fuel cell and water heater - ie. it produces electricity and hot water. Don't know how much hot water you get, but it sounds like a great idea.
The hot water is an optional extra, and it produces enough for an average family. I do to and I've been thinking of buying shares in the company for about 2 years now. Wouldn't want to rush in now.
I think they are really more German than Australian
The technology was developed at CSIRO ( my ex employer many years ago). Some people left and formed a private company. They started building the german plant about 18 months ago, as you said because of gov subsidies.
they do emit carbon dioxide
Next to none. Natural gas is nearly all hydrogen with some carbon impurities, so the carbon they emit is very small. The unit proper lasts indefinitely but you have to replace the fuel cells periodically. I don't understand your $1.52 liter calculation ? Is that gas or diesel your talking about ?
Apologies for any incorrect attributions above.I'm just a startled bunny in the headlights of life. L.J. Young.
We live in a free country. We have freedom of choice. You can choose to agree with me, or you can choose to be wrong.
Wait! No one told you your government was a sitcom?
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23rd July 2011, 11:58 PM #78GOLD MEMBER
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This must be another of those instances where wikipedia is wrong. Wikipedia says Natural Gas is mostly Methane but can be used to create Hydrogen by splitting water.
Originally Posted by wikipedia
woodbe.
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24th July 2011, 10:35 AM #79Intermediate Member
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Oxygen Imputities
Hi Damian,
you wondered how I worked out $1.52/litre for gas ?
I just read it off the bill - 104 litres for $157.95 is $1.52 a litre.
Please don’t think I am pleased about it, though. What do you pay for your gas ?
Also reading from the Orign account, 104 litres of LPG will emit 175.8kg of CO2 - that’s a little bit more than “next to none". The emissions from the Bluegen would be similar.
There isn’t any free hydrogen in the gas I get. Yes, the methane series are chemical compounds of carbon and hydrogen - but I have never seen them described as “nearly all hydrogen with some carbon impurities”.
So water (dihydrogen oxide) is mostly hydrogen with some oxygen impurities ?
I could get used to this.
Cheers,
Bob.
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24th July 2011, 11:02 AM #80
Solar
Solar, wind and water appear to be the sustainable renewables. Solar is the most attractive for me. It is the one with the most research, albeit pitifully small and there are downsides to it.
Large scale commercial plants occupy a huge area wether they are soalr thermal or solar voltaic. There is a 60MW plant proposed for Moree. It will have 150,000 solar panels and cover 160Ha. Another plant, 100MW at Ningen has 300,000 panels and covers a larger area. Incidentally the one at Moree looks like it is situated on good agricultural land, which is a shame if it is true. Food might eventually become more of an issue than energy resources one day, but that is another discussion.
So here is a suggestion. A while back (say 30 years) it was forbidden to have a water storage tank in your back yard. I know this because we moved to a new sub division in the Hunter Valley region in NSW and that is exactly how it was. Today where we live and in Toowoomba it is a requirement of every new building that it has a water storage tank. I think it may be around 20,000L, which is a reasonable size. I would not like to be relying on that if I entered a 6 month drought. 80,000L might get you by if you were very careful.
However, it is only intended to subsidise your useage and I am starting to digress here.
My point is that perhaps every new home should be designed with solar panels and connected to the grid. This just becomes part of the cost of house building the same as water storage, connection to sewerage and the electricity grid. Incentives would continue for existing dwellings too.
There is still the problem I raised in earlier posts of isolation procedure for maintenance, but I feel sure that could be resolved.
Regards
PaulBushmiller;
"Power tends to corrupt. Absolute power corrupts, absolutely!"
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24th July 2011, 12:25 PM #81Intermediate Member
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Ditch Coal and Nukes
Damian started this thread with a quote "Why don't we ditch nukes and coal ?"
Come on you blokes - at the moment there is as much interest in this topic as two of the others together.
So how about it ?
Could we do a brainstorm ? - ie. make additive posts and comments - don't waste time argueing with somebodies point unless it seems absolutely necessary ?
So I'll stick my neck out.
I think the lesson we should have learnt from fossils and nuke is that we need a energy economy that won't run out.
So take carbon (dioxide or whatever) - they say it is jiggering the environment.
So how can we turn it around ?
You know, 30 million years ago the sun shone on the swamps - the trees grew and died - fell in the swamp - and there you go, coal and oil.
And now we are digging it up - burning it - and would you believe it - the CO2 is causing greenhouse.
So what if we collected the CO2 out of the air using solar power - that is exactly what was going on in the swamps - photosynthesis.
Then we could use more solar energy to convert the CO2 to either carbon or methane - technology exists to do that.
Carbon can become a coal replacement - methane can be converted into synthetic petrol.
So we can continue using existing infrastructure.
So that gives us a CO2 neutral setup. All powered by the sun - and/or wind and/or water, if you want.
Fixes greenhouse and gives us a way to store solar energy - as carbon - burn it when the sun doesn't shine - gets rid of the argument that solar is no use at night.
So we move our energy economy into the natural carbon cycle - objective is to keep it balanced.
Ok, come on - who'se got some ideas ?
Cheers,
Bob.
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24th July 2011, 03:15 PM #82
Woodbe:
This must be another of those instances where wikipedia is wrong.
Your right I was thinking of town gas, sorry. Of course natural gas is methane because it is drawn off coal mines. I don't think too clearly at 10 pm.
I am prepared to believe I am wrong about fusion, but the memory of finding out they'd done a positive energy run is clear because I was so shocked when I heard it. I can't remember the source but I accepted it as reliable and I remember wondering why it wasn't headline news around the world.
Citybook:
See above. Do they really charge you $152 for GAS ??? sugar. That's a terrible ripoff. Thats LPG ? Is that bottled gas ? I think piped gas is cheaper.
Aside on gas: For many years we had cheap gas in Australia because there wasn't the infrastructure and the business case to export it. That all changed a few years back as several big gas terminals were built and the gas tankers became more common. We are now ramping up to world parity pricing on gas which will do for your cost of living pretty much what globalization has done everywhere else on your weekly bills. Good eh ?
So how about it ?
Actually I have thought that this thread has developed really well. Everyone has been respectful and the usual religious wars just haven't eventuated. Many thoughts people have expressed have interested me greatly. Lots of positive comments.
So what if we collected the CO2 out of the air using solar power
We have another technology for doing that, it's called wood. We used to grow it and cut it and burn it. Clever stuff that wood....
I think the economics of the carbon -> solar -> methane system don't stack up. Many years ago people used to get excited every time they discovered you can run your car on hydrogen, ethanol or whatever. The often and repeatedly accused the oil companies of conspiracies to hide these technologies (200 mpg carburettor etc) to keep us dependent on oil. You see the lunatic fringe aren't a recent manifestation, go to a nexus conference if you really want to be scared. Anyway the point is that the reason we don't ditch oil is it's cheap and no one wants to pay double to drive their car, no one wants their electricity bill to double either. It all comes back to $. Fossil = cheap, everything else = dearer. Go ask your average punter what they choose. For that matter ask your electricity retailer how sucessful the premium "green" electricity option on your bill is. I don't know but I bet it's about 5%.
Like I said you don't need conspiracies, you just need to accept people would rather spend their money on beer, makeup, polished bullbars, pizza, beer than petrol or electricity, and corporations are reactionary psychopaths. McDonalds doesn't care if you order the burger or the salad, they just want your money. Origin doesn't care if your buying coal fired electricity or tofu derived gas from them as long as they get a markup.
Bushmiller:
Good thinking there. I did the sums during the height of the drought and found I could get by with 30,000 liters, but that was one person doing 195 kilo liters a year (as I recall). That would comfortable see me through winter at the height of the drought based on the amberly rainfall gauge which is the lowest within 50 miles of me and the one that dropped most during the drought.
My point is that perhaps every new home should be designed with solar panels and connected to the grid
We saw a few years back that spectacular discounts could be negotiated by communities who bought many identical systems and had them installed in a specific geographical area. Naturally the Qld state government killed off the community initiative by announcing a similar scheme which they ran for 5 minutes, stuffed up then dropped. At the time with federal rebates people were getting 1 kW systems for $500.
Rather than mandate it in new homes I would rather see a consistent and simple rebate on installation, then everyone could embrace it who wanted to.
I get stuff wrong sometimes, but at least I admit it when I doI'm just a startled bunny in the headlights of life. L.J. Young.
We live in a free country. We have freedom of choice. You can choose to agree with me, or you can choose to be wrong.
Wait! No one told you your government was a sitcom?
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24th July 2011, 09:18 PM #83
This one is mainly in reply to Damian so I will try to comment starting with your last admission.
We have all fallen into the trap of believing a statistic which turns out to be a little less than true. Sometimes the misleading statement is deliberate and sometimes it is inadvertently untrue. As I mentioned previously you do have to look at the agenda of the individual or company making the statement.
It is a very human, very humbling trait to admit a mistake. All too often there is by others a tendency to home in and admisister the coup de gras. I find it difficult to admit I am wrong. It came as a terrible shock to me when my wife told me that although she loved me I wasn't perfect! I thought she had made a mistake. Apparantly not.
What is making this thread interesting is that it is a reasoned debate rather than a ranting and raving match. Incidentally, it doesnt much matter whether fusion has produced positive power, or whether it was sustainable for 0.5 secs or 2 secs. It is clearly unsustainable and possibly the furthest away of alternate energy sources without an earth shattering discovery.
Now, a comment on methane which I understand to be one of the worst of the greenhouse gases. I am willing to be shot down on this as I have not done research and I am currently spreading soft mattresses around me!
My suggestion for solar panels on new houses was made because it is easy to do. (hence my water tank analogy). I did also say that I was in favour of retrospective installations encouraged by incentives, as indeed they are now. I would however like to see a more consistent and reliable offer on the board at least as a base line with companies able to offer better deals if they wished.
I bought a book a while back called Sustainable House, which was published first in 1998. It detailed the experience of a family in inner Sydney that wished to be sustainable. They did it and in that regard were a long way ahead of their time bearing in mind they lived in a terrace house.
They identified that they required between 5kw to 6kw per hour for their circumstances. I mention this because most of the solar schemes are for 1.5kw with an option to go to 3kw, but not always at the same beneficial tarrif. In the book the family only got their electricty useage down by using gas as much as possible.
Revisiting your original statement, "Why don't we ditch nukes and coal?" I don't see that we can cut them straight out of the equation. We have to enter the transition period that I mentioned and stop the further building of these type of installations whilever they compound out climate change problems. The ground rules will change if nukes can be made safe and their waste disposal issues resolved and for coal if so-called clean technology becomes a reality. Right now and for probably 10 or 20 years I don't see this as an option.
So back to Bob's brainstorming. I will stick to my domestic solar installation for the moment as the first stage of kicking away the energy reform. If a household makes a decision today, it can become reality within a few months, maybe less.
Lead time for a new power station is probably a minimum of 7 years with conventional stations and about five years for the alternate gas, solar, wind and other technologies as they are in principle more simple. That assumes an easy passage through the approval stages. Probably an assumption that shouldn't really be made.
It is one of life's ironies that the simpler something becomes the more expensive it is. Normally. In this regard it's a little like ladies' underwear. The simpler, and smaller it becomes, the more expensive.
Regards
PaulBushmiller;
"Power tends to corrupt. Absolute power corrupts, absolutely!"
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25th July 2011, 02:58 PM #84
First problem I see is that while a water tank adds $1000 to a house a solar system sans rebates is $8k plus. That's a signifigant imposition for someone hocked to the eyeballs to build the thing in the first place. I accept you may be able to soften that with various things from rebates to builders bulk buying.
By the way I looked into the bluegen gas consumption. 9.5 Mj/hr for 1.5 kW or 12.6 for 2. I don't have gas and don't know what piped gas costs but I found a price in the 2.1 - 2.7 c per Mj range. That makes bluegen barely better than break even on fuel consumption alone so a huge payback time on the cost of setup. Makes no sense whatesoever without generous feed in tarriffs. I am probably wrong as they have gone from 11 - 19c in the last few weeks. I am disapointed.
I am not going to argue the GW thing here. I don't accept CO2 and methane are a problem and I don't accept the catastrophy scenerio. I'll leave it at that.
I saw one of these lecture tours of sustainable people years ago and the most amazing thing to me was most of what they did I do as a matter of course and the rest various neighbours do. We don't do it for enviromental reasons but rather because it's cheap. I live on small acreage so waste water gets dealt with onsite and goes to help trees grow, all organic waste goes into the soil not the bin, that sort of thing. Just doesn't seem revolutionary to us but I suppose I don't live in a Mc Mansion on 400 sqm and spend $300 a time at Woolworths...
I am always happy to be corrected, but there is a condition. The correction has to be proven with hard data and repeatable methods. I don't buy "believe the expert", that's religeon not science.I'm just a startled bunny in the headlights of life. L.J. Young.
We live in a free country. We have freedom of choice. You can choose to agree with me, or you can choose to be wrong.
Wait! No one told you your government was a sitcom?
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25th July 2011, 03:57 PM #85GOLD MEMBER
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Th bluegen could be good because you might replace or supplement an unreliable street power supply with a reliable one for not much of an overhead. Plenty of people in that boat. Even if you only got the standard 20c/kWh or whatever for feed-in, it might make sense to some people, but definitely not an option for all.
That you can generate power at home using gas at anything like the retail cost from the street. is pretty amazing.
As far as the solar option on new homes, its a nice idea, but until the price comes down it won't happen. What would be a great first step would be a building code requirement for roof aspect to maximise the solar potential on any new home.
I'm not going to argue the AGW thing either. If we engage in that it will only poison the thread. Same for name calling...
woodbe.
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25th July 2011, 07:14 PM #86Bushmiller;
"Power tends to corrupt. Absolute power corrupts, absolutely!"
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25th July 2011, 07:52 PM #87Skwair2rownd
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G,day Bob. Thanks for your reply. I do know about building simple solar systems and about the flat black plastic pipe for pools. I have limited roof space and was wondering whether the evacuated tube heater is more efficient than the copper plate and pipe affairs.
I expect it will cost more but that may not , ultimately, be the point.
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26th July 2011, 09:37 AM #88Intermediate Member
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Solar Hot Water
Hi Artme,
well I am a big believer in simple things.
Have you looked at Build it Solar ? Lots of stuff you could use there.
For instance
"http//www.builditsolar.com/Projects/SpaceHeating/RenwMagLargeRoofCollector.pdf"
is the system John Hermans built in Victoria - pretty amazing.
There is a study from Glascow
"www.esru.strath.ac.uk/Documents/MSc_2001/dimitrios_panapakidis.pdf"
about different sorts of solar heaters - some good technical stuff, but not Australia.
There is a big debate about the relative efficiency of evacuated tubes and absorber plate.
"http://www.pmengineer.com/Articles/Column/2008/08/01/Competing-Collectors-Part-2"
and a bit in previous columns about construction.
Notice, the man says "...be sure to remember, the numbers don't tell the whole story."
And because I am not sure if you understood that I was saying before that the EPDM swimming pool heater pipe can compete with the copper and evacuated tube collectors - here is a study published by CSIRO on the subject.
"http://www.publish.csiro.au/nid/79/issue/6345.htm"
The paper is at the bottom of this page, and you will have to download the pdf.
I do go off a little about this - O'Keefe and Francis did this work in the late '80s - published it - and it has been soundly ignored since then. It really riles me when Oz is described as innovative and clever - what we do best is ignore really interesting science like this. End of rant.
From what you say about space the Hermans thing may be too big - but he gives detailed construction information that could be used anywhere.
Again, Build it Solar has a section on studies and information, and you will have to make your own mind up on this.
For my own two bobs worth, the glass tubes are fragile. Technically that is not included in an efficiency calculation - but for me it's a biggie.
For those links - I put them in inverted commas because the Woodies computer tried to help and scrambled the URLs - I checked them - they do work - you may have to copy and paste the links though - take off the quotes, of course.
Anyhow, hope this helps.
Cheers,
Bob.Last edited by citybook; 26th July 2011 at 11:12 AM. Reason: Add links
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26th July 2011, 12:27 PM #89Intermediate Member
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Bluegen Fuelcell
Bit more information on the BlueGen.
Harvey Norman is going to have an Australian agency, and the price is going to be around $45,000 - it only connects to piped natural gas - feed in tariff is not available.
It doesn't have the approvals yet to be connected as an appliance, but I gather that is in progress.
There is a website at
BlueGEN | Harvey Norman Solar
and they plan to post information there as they get it.
Cheers,
Bob.
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26th July 2011, 03:26 PM #90Intermediate Member
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The Methane Gun
Now if I can just get a little spin going here, we aren't talking about global warming...
There was a comment "...methane which I understand to be one of the worst of the greenhouse gases..."
If we are to suppose there is a greenhouse effect which says that the surface temperature of the earth rises in response to increasing concentration of certain gases in the atmosphere.
Very broadly, the process for this is by way of fiddling with the rate that heat comes to the earth compared with the rate that heat leaves.
It is worth saying that if this didn't happen there most likely wouldn't be much life on Earth.
Then the supposition also is that water vapour contributes roughly 70% - CO2 roughly 20% - and the rest all together about 10%.
Maybe methane makes up half of the "rest" - so in that regard it is not too bad.
The problem is, it is thought that volume for volume the effect methane has is between 20 and 70 times greater than carbon dioxide. Big range there, but I think basically we aren't sure. But it is a fair bit more.
So yes, methane does have a significant greenhouse effect.
However.
What could be an interesting problem is the presence of methane hydrates in large deposits, usually under ice and usually under pressure. It appears that most of this has been there quite a while.
And, even though the science is sketchy, it would appear that there is a hell of a lot of methane there. Some people think more than the rest of our energy deposits put together ?? I wouldn't know.
The Methane Gun is, what happens if this methane gets released.
The ABC did a Ockhams Razor program on it
"http://www.abc.net.au/rn/ockhamsrazor/stories/2009/2577170.htm"
Cheers,
Bob.
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