Home > Regular Features > Sandpit

Sandpit

October 8th, 2012

A new sandpit for long side discussions, idees fixes and so on.

Categories: Regular Features Tags:
  1. Ikonoclast
    October 9th, 2012 at 08:41 | #1

    Solar panel performance in Brisbane is surprising if my experience is anything to go by. With a near ideal orientation almost due north and a near ideal roof pitch of 22.5 degrees for fixed panels the results are interesting. (The ideal pitch for fixed solar panels in Brisbane is 27.5 degrees.)

    I have found that clear winter sun (about a month after the winter solstice) produced higher peak generation (about 5.1 kW on 5.5 kW nameplate capacity) than clear sun just over two months later (about 4.8 kW) based on several observations over a week in each case. Peak generation tends to occur at about 11:00 to 11:30 on my system. Based on these results I expect to make more power in summer only because of the longer daylight hours and not because of higher peaks.

    I suspect that the main reasons for higher peak electricity generation in late winter are;

    1. Cooler panels operate more efficiently (less electrical resistance).
    2. Winter skies on cloudless days are clearer. Summer skies carry smoke and dust particles.

    I say the results are surprising because summer sunlight feels a lot hotter (more energetic). My improved solar hot water performance (evacuated tube technology) in summer certainly proves summer sunlight is a lot hotter so why does this not translate into better solar PV performance? Do the two points above explain it all or are there other factors? I’ve hosed the dust of my panels to eliminate that possible impediment. Significantly different peaks on subjectively similar, sequential, clear days have convinced me that particle loads in the air vary and the difference in general brightness or haze in the sky is not detectable to human eyes (or difficult to subjectively compare 24 hours apart.)

    It all makes me wonder whether solar panels should have finning for air cooling on the reverse side to improve summer performance. I’ve read of cooling systems being proposed for solar panels (even water cooling) but the replies make the claim that it is more cost effective to just add a few more panels if you want more power.

  2. BilB
    October 9th, 2012 at 09:52 | #2

    If you have a swimming pool then cooling the panels is more effective.

    You do realise that in writing up solar results such as these you are inviting a visit from Peter Lang who would not doubt point out how your experience has been a fluke, perhaps the result of a freak solar flare, and your system will be plunged into darkness for the rest of eternity and ultimately be a waste of money.

  3. Troy Prideaux
    October 9th, 2012 at 09:54 | #3

    Well, doing some quick BOE calcs, strictly in terms of distance, the electromagnetic energy from the sun you could potentially get at the poles is 99.99% of that at the equator using the inverse-square law. So, there’s not much detectable difference. The massive difference in temperature you experience is primarily caused by the angle the sun hits the surface ie. a given area of solar radiation has to heat a lot more land mass the more it’s angled away from perpendicular or normal to the surface.
    On the moon, where there’s no atmosphere to diffuse the localized heating of the surface, you can virtually (theoretically) feel the same temperature on the poles as the lunar equator if you’re facing the sun at the same angle.
    So, yeah, PV panels definitely are more efficient at cooler temperatures so depending on the angle you have them to the sun, I can imagine how they can produce more electricity in some cooler days provided you have direct sunlight on them
    The maximum solar light energy you can potentially receive at a given location would likely be on a cloudy day with only light cloud surrounding, but with a clear hole where the sun pokes through. In that instance, you still get your direct sunlight, but some of the surrounding sunlight is diffused by the clouds of which you should receive some of.

  4. Ikonoclast
    October 9th, 2012 at 11:03 | #4

    @Troy Prideaux

    Interesting points. I was already aware of the solar incidence issue so the results probably should not have surprised me so much. On a clear day, unobstructed panels at a perfect right angle to the incident sunlight should receive the same insolation summer or winter (provided atmospheric conditions are identical) EXCEPT that sunlight in winter is effectively travelling through more atmosphere (and thus more atmospheric interference) being incident at a more acute angle. However, I was surprised that clearer winter air and cooler panels gave me more peak power even though the incident angle on my fixed panels would have been less nearly optimal than in summer.

    Can anyone tell me which wavelengths of elctromagnetic radation solar panels can generate electricity from? Is it all wavelengths? Or are solar PV panels effectively “opaque” or non-generating for some wavelengths?

  5. BilB
    October 9th, 2012 at 12:06 | #5

    A very narrow band Ike. But science is working on that furiously. That is one of the essential differences with our GenIIPV system, the solar elements use much more of the frequency band, hence one of the principle increases in efficiency, the sum of which take it to near 60%.

  6. Hermit
    October 9th, 2012 at 16:27 | #6

    Ikonoclast have a look at BoM’s insolation map for May to July 2012
    http://www.bom.gov.au/jsp/awap/solar/index.jsp?colour=colour&time=latest&step=0&map=solarave&period=3month&area=nat
    I’d say the combination of high latitude and subtropical winters work in your favour, more so than reduced internal resistance. I call upon Queensland to renounce coal and go solar.

  7. BilB
    October 10th, 2012 at 07:50 | #7

    Ikonoclast,

    40% of the earths human population lives in that solar favoured tropical zone, and by 2060 it is projected that what is left of the human population 60% of them will live in that zone. So from an energy perspective 60% will have “no worries” within 50 years if politicians have nothing to do with it.

    But therein is a question. On average,….on Global Warming,….are politiciians a help or a hinderance?

  8. Ikonoclast
    October 10th, 2012 at 09:27 | #8

    I agree. Solar power is the future. Fossil fuel interests resist it as they do not wish to be left with stranded assets. In resisting it, they have already condemned us to at least 2 to 4 degrees C of built-in global warming. Anything over 2 degrees is going to disastrous for human global civilization, severely curtailing it even if not totally destroying it. We, the consumers bear a responsibility too as we buy far too many cars, air-conditioners and flat screen TVs.

    I also note that the peak oil doomsters (of which I was one in the past) do our future prospects a disservice by decrying the feasibility of solar power. By doing this they play right into the hands of the destructive “burn it all baby” agenda of the fossil fuel oligarchs.

  9. Ikonoclast
    October 10th, 2012 at 11:15 | #9

    Troy said, “The maximum solar light energy you can potentially receive at a given location would likely be on a cloudy day with only light cloud surrounding, but with a clear hole where the sun pokes through.”

    I somewhat dicounted this statement thinking that blue sky may be reflecting/refracting almost as much extra light as clouds. However, an observation I have just taken proves Troy correct. In conditions closely approximating what Troy said (with many fluffy white clouds as well as grey clouds but a nice hole for the sun to shine straight through) my Solar PV power production went over 5,000 watts where 4,000 to 4,500 watts seems more usual on clear blue sky days at that same time of day.

    In summary, my observations to date now show that;

    1. Winter solar PV production in Brisbane is as good as summer in peak and general profile terms and only suffers by the day being shorter. I still suspect winter solar PV production in Brisbane to be as good as 75% of summer.

    2. Broken cloud days create situations where you can gain as well as lose power production. The net effect is probably still a loss but the gains from the “Prideaux” effect cancel some of those losses.

    Summary. Solar power is lot damn better than you think it is if you have never had it installed and monitored its performance. Of course, getting the full feed-in tariff and having the grid available as an effective giant battery for “storing” power and then giving back power as required is an enormous advantage.

    Properly utilised, even in an unsubsidised manner, an existent power grid is an asset which can be utilised and leveraged by individual generators of power be they micro, niche, or large generators. The problems of accepting solar power into a grid are exaggerated by opponents of solar power. In my area, a visual “straw poll” of homes (where I can see their north facing roof) indicates that at least 15% of homes have solar PV power and that average system size is probably 3.5 kW capacity. In addition most of these 15% also have solar hot water systems and some without PV panels have solar hot water. I am aware of no supply or voltage problems troubling my suburb or my house.

    With solar power distributed all over Brisbane and S.E. Qld the input is “smoothed” and also predictable in the sense that clear sunny production is predictable, clouded production is predictable and cloud patterns can be followed and their effects on power production also predicted at least a few hours ahead.

  10. Ikonoclast
    October 10th, 2012 at 11:29 | #10

    I might also add that my numbers show that my solar PV (5.5 kW nameplate cpacity with 22 panels) on average will be fully powering my home with 4 adult persons and another home that has equal power use. This takes into account the fact that I can feed excess power to the grid and “get it back” or later when i need it or effectively sell it to someone else. My solar hot water system is helping to realise this equation of course.

    We don’t really try to conserve power either other than being sparing about heaters in winter and air-con in summer – only one room is air-conditioned and air-conditioning is only used in there about 60 days a year for maybe 12 hours of each day. As well as the needs of normal house we run a biocycle waste system with electric pumps and aerators.

    Thus, if half the houses in Brisbane had 5.5 kW solar PV systems and solar hot water then domestic power would present no net drain on other generation methods over the 24 hour period. Commercial and industrial power requirements are higher by day. As night falls and commercial and industrial requirements decline this will in broad terms counteract the loss of solar at the end of the day. The fit is better than many people think and nicely refutes the peak demand argument.

  11. BilB
    October 10th, 2012 at 12:14 | #11

    That is pretty cool, Ike.

  12. October 10th, 2012 at 13:20 | #12

    I would argue that peak oil doomsters do not uniformly rubbish solar. Those who understand peak oil but argue against solar in my experience are usually coming from a BAU position and can be quite trenchant about it.

    Back to solar:

    Back in 2007, the Lord Mayor of Brisbane, Campbell Newman, spent $100million of Brisbane ratepayers money to start “Green Heart City Smart”.

    At the time I made the following observation:

    “According to ‘Origin’ energy’s website, you can get a solar hot water system fully installed for about $2,000. So you could also spend that $100,000,000 to buy 50,000 solar hot water systems fully-installed on Brisbane rooftops. That would save those households a combined total of about $15,000,000 every year in electricity bills and cut greenhouse emissions by about 150,000 tonnes every year! So your $100,000,000 would save 50,000 lucky homes $150,000,000 over ten years AND reduce emissions by 1.5 million tonnes. Why wouldn’t everyone embrace such practical investment? Unless of course you were in the business of selling coal-fired electricity…. oh, I see.”

  13. Ernestine Gross
    October 10th, 2012 at 19:55 | #13

    Ikonoclast
    Re your @13 on the Boycotting hate radio thread.
    You asked some questions about something I wrote:
    1. “What is the distinction between quantification and measurement and why is the distinction important?”
    This is a fair enough question, for which I have no easy answer, other than to say under some conditions the distinction is important. See: http://en.wikipedia.org/wiki/Quantification
    Apologies for not saying this in the first place.
    2. What is “incentive compatible mechanism” and why does the statement in parenthesis (ironically?) illuminate it?
    An incentive compatible mechanism is an application of game theory to provide a solution to an incentive compatibility problem.

    For ‘incentive compatibility’ see: http://www.dictionaryofeconomics.com/article?id=pde2008_I000027

    An empirical example of an incentive compatible mechanism, which we encounter in everyday city life, is the traffic light system. Each and every road traffic participant is modelled as ‘a player’ and is assumed to derive positive utility from a) getting to the desired destination alive and with an undamaged vehicle, and, b) getting there in the shortest possible time. The mechanism consists of a set of traffic light rules (and other traffic rules). The mechanism doesn’t work perfectly. Accidents do happen and at least some of these are due to some ‘players’ not adhering to the rules.

    Designing an incentive compatible mechanism for ‘performance schemes (eg bonus and other incentive schemes)’ is easier said than done. There is a vast literature. The following link may provide the flavour of the difficulties. http://scholar.google.com.au/scholar?q=incentive+compatibility&hl=en&as_sdt=0&as_vis=1&oi=scholart&sa=X&ei=3vZzUPGjBKGdmQWYtIHABg&ved=0CBoQgQMwAA

    (I can’t think of any way to apply the method of critical thinking and post-modernist de-construction which would lead to a reduction in road casualties or a reduction in the negative consequences of manipulable performance incentive schemes. Manipulable performance incentive schemes have the property of being counterproductive. Impatient perhaps but not irony on this occasion.)

  14. Ikonoclast
    October 11th, 2012 at 08:22 | #14

    @Ernestine Gross

    Thank you Ernestine. Most illuminating. I understand much better now what you were driving at. The problem is that I lack some of the specialist knowledge and specialist terminology which you use for succinctness.

    In my late, lamentable, unillustrious career in the Federal Public Service I was consistently frustrated and angered by the transition from a Public Service that Nugget Coombs would have recognized and approved to a Public Service taken over by managerialism and corporatism. I am sure that my personnel file, if not already stamped “never to be promoted” because of my Union activities, was finally so stamped when I burst out at a meeting with managers and railed against matters using terms like “creeping managerialism, fad management, lack of organisational memory and faux quantification”.

    In the last work section I was in (it was sort of like being sent to Coventry or even Siberia for a person of my age and experience) I saw the most extreme mess and stress possible with much of it being caused by the managerialist approach. I had a key insight, “This place is going to give people heart attacks.” I took an early retirement soon after.

  15. October 11th, 2012 at 09:00 | #15

    Sunlight at ground level is about 3% ultraviolet, 44% visible light, and about 53% infrared. Generally, solar PV only makes use of the visible light part. In general, life only makes use of the visible part for photosynthesis and sight. There is a lot of infrared, but as there is less energy in each individual bit of infrared than there is in visible light it’s harder to extract energy from it. While our eyes can detect a single photon of visible light, the thermoreceptors in our skin are not so sensitive. (Note that while our eyes can detect a single photon of light, it’s not as good as it sounds due to their habit of detecting a single photon of light when there has been no such photon.) But people are working on getting solar cells to use more infrared.

  16. Ernestine Gross
    October 11th, 2012 at 09:40 | #16

    @Ikonoclast

    And ‘they’ wonder why labour productivity declines! I believe I’ve got a reasonably good idea as to what ‘the mess’ looks like. Incidentally, senior professional people (eg chemists, actuaries, dentists, ..) in private industry have told me about similar experiences. One fellow told the class that he told his ‘boss’ if you hire a consultant then I’ll resign because it means you don’t trust what I do. He came from the sugar industry. I’ve watched ‘real world’ private industry managers challenging an academic proponent of corporatism and managerialism by asking him straightout: “who is behind this”. Beautiful.

    A related topic of interest to me is the enterprise agreement industry. It is a very profitable industry for the legal profession, the HR people, and a lot of consultants (please don’t ask me for exact data because it would take too much of my time). No matter how much I try to challenge my hypothesis about the underlying conceptual model and no matter how much I read, I reach the same conclusion. The underlying conceptual model consists of two ‘agents’ (‘agent’ is a generic term for decision maker which is useful in theoretical work when the institutional environment is either not known or deliberately set aside): ‘the employer’ and ‘the employee’. These agents may have representatives (HR or legal officers; and a union representative). This model fits very well the world for which libertarian models would work too. This is not the world we live in. In the so-called real world, there are organisations – private and public. And these organisations have internal structures (not excluding chaotic systems). This introduces some interesting complications (speak frustrations for those in it). For example, it is not always easy for an arbitrarily chosen ‘employee’, a person, to find out who the person is that has the role of ‘the employer’. Of course ‘every employee’ (person) knows that the CEO has something to do with being ‘the employer’. But the same ‘employee’ also knows that access is barred because these people can’t possibly individually talk with say 20,000 employees. Looking at it from the CEO’s point of view, it doesn’t look much better because he or she has to rely on the information channelled up – in possibly filtered form. On the way up and on the way down – assuming a hierarchical structure – there are several self-interestes people and not all of them follow the traffic rules. The problems arising from this issue alone are then handled via early retirement or via pay-outs – no? But this is the easy bit. Management ‘theorists’ (not least those who come from the world where the issue of who is going to do the dishes in a commune is assumed away for ideological reasons) are not all in favour of a hierarchical structure. There is something called a ‘matrix structure’ which more or less insures that nobody knows who is supposed to do what (even those lucky few who find themselves in a corner cell have at least 2 other ‘managers’ to deal with and can’t be sure about those ‘managers’ with whom their cell intersets at the corner. Is it surprising that cronyism thrives in such an organisational structure? Is it surprising that ‘power’ of position (actual or usurped) is the only feasible way to arrive at a decision?

    I could go on and on.

  17. October 11th, 2012 at 11:51 | #17

    And I’ll mention that sunshine is a few percent more intense in the summer in the southern hemisphere on account of how we’re slightly closer to the sun at that point.

  18. Ikonoclast
    October 11th, 2012 at 12:28 | #18

    @Ernestine Gross

    Yes I could go on and on too. So I will try to be succinct. From the point of view of my amateur theorising, everyday management is about information flow, coordination, control and command. I put them in that order as that is the order of importance in my opinion. Without information flowing you cannot coordinate, control and command. It is also possible, I think, to see coordination occurring without much overt control and command at least at the time of observation and often for extended periods. This means that the individual workers (agents) have internalised and “communalised” to some extent the coordination, control and command imperatives implicit in their work and also (often but not always) made explicit in control and command “edicts” from mangers.

    Control and command themselves work best (in a civilian setting where people are used to and expect certain rights and considerations) when subtle, minimalist and dare I say respectful. As Francis Bacon, the philosopher, said, “To command nature, you must obey nature.” When commanding human and social natures you need to pay attention to human and social nature.

    Coordinated, effective and efficient action (again in that order) at the “coal face” is what an organisation should be about. On this view, line management and middle management are ancillary activities not central activities. This is not to say that performing line management does not need significant technical and personal skills or some better remuneration. It is to say that management should not be “fetishised” and management (a specialist stream) treated as somehow superior to other specialisations.

    It would take a lot of exposition to tease out the above thought out so I will leave it hanging except for a few examples. A technical specialist, say a senior statistician, economist, systems analyst or university professor should be on par with senior (strategic) management in terms of pay and influence on institutional strategy in their respective institutions. That is, there is no justification for regarding even pure upper management and nominal overall command as the pre-eminent specialisation or even as first among equals. Such a theory would require a more collegiate approach to senior strategic management and one which drew from more disciplines other than just business management. It would mean a move away from mangerialism as, for example, senior specialists including the nursing senior would have more say in running hospitals and senior professors more say in running universities.

    As to the issue of endless restructuring (a common bane of managerialised systems), it ought first to be remembered that form should follow function. I am a firm believer in this principle and often use an analogy from anatomy. The evolved structural differences between hand and foot would be baffling if we were not fully aware of their different functions and how they evolved to fulfill those functions. Thus the first step in designing an organisational structure or sub-structure is to fully analyse the functions it will be required to perform. Only then can the physical and personnel structure be designed.

    Any restructure proposal ought first to pass a number of tests. Have the functions changed? Has the needed scale of operations changed? Has the existing structure proved to be badly designed for existing functions? The default bias ought to be in favour of the existing structure and the onus of proof on the proposal for structural change. This is because strcutural change is disruptive and expensive. To undertake it for doctrinaire, faddist or sectional interest purposes is against all of worker, client, customer, institutional and public interests. Particular care ought to be taken to fully work and document cases for major structural change and archive them whether successful or not. Subsequent proposals and studies for major structural change should first study the existent insitutional archives for related studies. In this way an institutional memory is retained and utilised and organisations not go round in circles every 3 to 5 years, for example centralising and devolving, centralising and devolving.

    Finally, much as I would like to think differently about myself and others, complete self-management and self-regulation do not generally work where there is conflict of interest and temptation to operate with self-interested motives. There will always be a need for various forms of mutual oversight to keep each of us on the up and up; ie. to keep us all reasonably legitimate, honest and respectable.

  19. Ikonoclast
    October 11th, 2012 at 13:05 | #19

    To continue…

    The issue of hierarchical verus matrix management is an interesting one. For all its faults, I come down on the side of hierarchical management at least for public service insitutions. The PS is unavoidably rule bound. Each department administers an Act or Acts and does this via Policy Manuals, Operational Manuals and Clerical Guides. Each member of the public has the right to expect that laws, rules, regulations, obligations and entitlements will be adminstered and implemented fairly, consistently and impartially. Only good information flow, good coordination, and clear lines of control and command from Parliament down can actually ensure this. This can make the PS slow, hidebound and seemingly a tyranny of numerous and minute rules for both staff and clients. The alternative (excessive discretion) would be worse. It would make it capricious, open to influence and all sorts of nepotism, bribery and corruption.

    However, the need for hierarchical control of the adminstration of laws, regulations etc. directed to the public need not wholly catch up in its net the issue of internal management, control and administration. But that’s another story and a very long post.

    As to the issue of early retirement and/or pay-outs. It is a damn shame that a lot of intelligent people, good critical thinkers and good workers just get bounced out of public organisations these days for not toeing the mangerialist-corporatist line. Even discounting myself as a bit of a disaffected crank I saw plenty of really good people (better men and women than me Gunda Din) pushed aside or pushed out. The ideological, managerialist conformists have triumphed ever since the first Howard government in Australia, much to the nation’s detriment. To my mind no-one put it better than Micheal Pusey in “Economic Rationalism In Canberra”. That book was ahead of its time and predictively spot on.

  20. Bring back Birdy at Catallaxy
    October 11th, 2012 at 14:50 | #20

    Ernestine @16, thank you for your exposition of how Griffith University operates. ;-)

  21. Xevram
    October 11th, 2012 at 17:46 | #21

    Hermit :
    Ikonoclast have a look at BoM’s insolation map for May to July 2012
    http://www.bom.gov.au/jsp/awap/solar/index.jsp?colour=colour&time=latest&step=0&map=solarave&period=3month&area=nat
    I’d say the combination of high latitude and subtropical winters work in your favour, more so than reduced internal resistance. I call upon Queensland to renounce coal and go solar.

    LOL on that but just for the record I reckon we should all call on the NT govt. to renounce gas and coal fired and go solar.
    Not going to have much luck, we have a new Govt. here and they are more intent on other important issues, like how to downsize the NTPS without actually firing anyone or forcing redundancies (which they can not afford).
    I would love to write an explanation of how Charles Darwin University works, sadly I could not do it without a realxation of the language code on this site.

  22. Salient Green
    October 11th, 2012 at 17:58 | #22

    @Troy Prideaux
    I have noticed the lensing effect of clouds on my solar system with output from a 1500W system peaking at 1650W for short periods. This effect actually caused my inverter to turn off, occasionally at first and increasingly after 6 months of operation until I had to get an electrician in who changed a setting and it’s been ok ever since.
    After one year in operation it produced an average of 6.52kwh per day at Mypolonga, SA which is just above the average for Adelaide at approximately the same latitude.

  23. Ikonoclast
    October 11th, 2012 at 20:44 | #23

    @Ronald Brak

    There is an interesting device which can produce electrical power from more of the electro-magnetic spectrum. It’s the nantenna (nanoantenna).

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

    http://phys.org/news/2011-05-solar-product-captures-percent-energy.html

  24. Ikonoclast
    October 11th, 2012 at 20:50 | #24

    This is also interesting. Solar energy, when almost fully harvested across all the spectrum, could really surprise us. There is an astonishing amount of energy there to be harvested.

    http://phys.org/news/2011-04-polymer-solar-thermal-device-home-money.html#nRlv

  25. Ikonoclast
    October 12th, 2012 at 06:57 | #25

    And this since one of my comments above is in moderation for two links;

    http://phys.org/news/2011-05-solar-product-captures-percent-energy.html

  26. BilB
    October 12th, 2012 at 07:53 | #26

    That is very interesting, Ike, but I would not hold my breath for that particular technology. Whereas it is exciting there are real problems in making very specific nanoparticles in huge quantities. But I suspect that it is a very significant pointer for the future. There is also an issue with the biological risk of particles so small that they can just slide into cells and interfere with the internal working. This is a major problem with moon habitation also. The finer lunar dust is submicron and therefore potentially dangerous to life in a similar way that asbestos is dangerous (I believe). So very large surfaces which might shed submicron particles into the atmosphere is a very real danger.

  27. October 12th, 2012 at 13:15 | #27

    Maybe nantennas will be the solar panel of the future, but at the moment they aren’t commercial and have a few problems that will keep them from being competitive any time soon, as far as I can see. One is they aren’t more efficient than more conventional solar cells at the moment, and it’s difficult to get usable energy out of them once they’ve absorbed light energy. Their small size shouldn’t be a health risk though, as they will have something over them to seal them in otherwise they wouldn’t last long exposed to the elements. Of course, if contact with them is dangerous precautions would need to be taken. If we really want high efficiency we can currently get over 40% efficiency by stacking solar cells on top of each other to make multi-junction cells. We just don’t use them currently because of the cost, it’s cheaper to just put up more solar panels, but the potential is there if we can figure out a cheap way to make them.

  28. BilB
    October 12th, 2012 at 14:43 | #28

    That technology has quite a few hurdles, RonaldB. But the approach is quite thrilling. What they are effectively attempting is to capture every single photon and converting that energy into electron displacement. Elements on butterfly wings have micro pores that can capture single photons and re-emit them at a different frequency thus giving the wings their bright vibrant colours. These scale like elemts are formed inside single cells and exit the cell to sit on the surface and perform this colouring process. So how do we match this micro manufacturing process in such a way that the photons yield an electron. That is what these micro antennas attempt to achieve. Nature has the benefit of biological manufacturing techniques, we need to find a way of achieving that detail density. Not at all easy.

  29. BilB
    October 12th, 2012 at 15:20 | #29

    Google gyroids. Set images.

  30. October 14th, 2012 at 12:19 | #30

    I’ve just seen a claim that black silicon PV may be ready commercially “soon”. Black silicon is able to make use of near infrared energy and apparently can be over 18% efficient. This is worse than the best PV cells already available, but if they can do it at a lower cost it should be a success. However, I imagine they will get even hotter than conventional solar cells. But the higher the efficiency, the lower the heat problem as a greater proportion of sunlight energy is converted into electricity rather than heat.

  31. BilB
    October 14th, 2012 at 13:21 | #31

    The trick is for black silicon to be used in conjunction with conventional silicon in the same panels that should take the flat panel above 20.5% heading towards 30% efficiency.
    Costs will steadily reduce overall as solar uptake steadily accelerates.

    My last family power bill for a quarter was $900, and, frankly I am not especially upset about that as it brings forward the time when I install a compound solar package on my family home. I applaud the greed of the grid electricity suppliers, as they are maximising the incentive for me to eliminate them from our budget both domestic and business.

  32. October 14th, 2012 at 13:58 | #32

    Well, I guess black silicon would make multjunction cells more efficient. We just need a cheap way to make them. I’m sure someone is working on it.

  33. Hermit
    October 14th, 2012 at 17:18 | #33

    In my opinion the feed in tariff should be based on supply and demand, including the possibility of curtailment of excess supply such as on cloudless cool sunny days. This would have to be done with smart meters perhaps using 15 minute NEM prices. If you refrain from aircon during a late afternoon scorcher you get a high FiT. In the last few years many have based their payback calculations on the unsustainable FiT at the time of purchase, say 44c per kwh.

    Thus on cool sunny days the idea would be in effect ‘use it or lose it’ if the FiT was a mere 2c as in parts of the US. However that doesn’t mean homeowners will buy battery banks for several reasons. Those reasons include lack of subsidies, bulk and unsightliness, danger from inquisitive kids, fast depreciation on batteries and uncertainty whether the batteries can be replaced every few years if the homeowner has left the workforce. If the homeowner also has to pay a few hundred extra for a smart meter that will be an additional deterrent.

    If the small PV component of the RET is axed or watered down (remember Pr Q is on the review committee) then uptake could halt. I think this is what Climate Minister Combet wants as he keeps telling us CO2 avoided by small scale PV costs over $400/t.

  34. October 14th, 2012 at 17:58 | #34

    Actually, now that I think about it, multijunction cells would already have a layer for near infrared. But black silicon is a way to utilize near infrared in a single layer, and so hopefully will be cheaper than double or multijunction cells, even if it won’t help us bump up the efficiency of multijunction cells.

  35. October 14th, 2012 at 18:20 | #35

    Well, it looks like Climate Minister Combet either can’t do primary school maths or for some reason he has chosen not to. At current installation costs $400 will buy about 133 watts of installed solar capacity before Renewable Energy Cetificates are figured in, which will generate about 7,000 kilowatt-hours of electricity over 30 years which would eliminate about 4 tonnes of CO2 emissions in a coal heavy state like Queensland. But it would be completely stupid to think that means the cost of avoiding CO2 emissions with PV is $100 a tonne because solar PV actually produces electricity, which is sort of the whole point. With a discount rate of 7% a kilowatt-hour of solar electricity costs about 15 cents, or about 10 cents cheaper than grid electricity, so under the right circumstances $400 of point of use solar will reduce carbon emissions at a cost of around negative $175. That is, for each tonne of emissions avoided the owner of the system will save about $175 on grid electricity. If the system owner ends up exporting a third of their solar power and only receives 8 cents a kilowatt-hour for it, then they’ll only make about $100 for each tonne of CO2 avoided.

  36. Chris Warren
    October 14th, 2012 at 19:59 | #36

    I wish all those enthusiastic proponents of solar power would look at the negatives. Industrial solar (and wind) occupies 100′s of acres of real estate, and does not suit urban environments dominated by flats. A growing population may render solar as impracticable. It is a pity that there is a market for solar for some lucky people today because this artificially attracts funds from better alternative. For example scientists are developing means to extract energy from fresh and salt water. They suggest:

    it should be possible to extract 1.6kJ of energy per litre of fresh water. With a cycle rate of 1 per second, this should generate a power output comparable to that of existing membrane-based methods. The need for a fill-flush cycle driven by pumps is a drawback, but all the same this looks like a worthy competitor. With luck and good engineering, every major estuary might one day have its own blue power plant.

    see: http://www.rsc.org/chemistryworld/Issues/2009/September/ColumnThecrucible.asp

    If governments and universities made greater efforts in this area, our future will be a lot more prosperous.

  37. BilB
    October 14th, 2012 at 20:35 | #37

    The panels that I am interested in as a temporary measure are 235watt 20% efficient panels that cost around $400 each. Ignoring installation and using your energy conversion formula these panels will produce about 390 kilowatt hours per year and 11.7 megawatt hours over 30 years, and prevent the release of 11 tonnes CO2 over that same time. So that one $400 panel will keep $3,300 in my family budget that would other wise be paid to some EnergyCorp.

    That is the incentive that matters.

    So 10 of those panels will be worth $33,000 to the family budget, and if I put a $3000 solar water heater beside them that will add another $9000 beside that (offpeak saving). And if I put 20 panels on the roof that goes up to a total of $76,000 over the 30 years. Of course for 20 panels I would need some stroage to fully utilise that delivery level.

    But there is more yet. If I buy and EV and charge it from my panels then I could argue that the petrol that I am avoiding buying would improve that return even further and the EV batteries become my storage. In that calculation the EV would use about 40 kilowatt hours per week and offset $40 petrol in the so doing. 1560 fills will offset $62,000 petrol. Add $15,480 for the balance of the electricity and $9,000 for the solar hot water and the $11,000 system is worth $86,480 to the family budget over 30 years. Or $2,900 per year.

    That is an annual incentive worth having especially considering that that is pre tax so i have to earn at least $3,770 (tax included) to pay EnergyCorp and Shell Oil for my energy. And that is being conservative considering what will happen with energy prices over that timeframe.

  38. BilB
    October 14th, 2012 at 20:50 | #38

    You’ve got to be kidding, Chris Owen.

  39. October 14th, 2012 at 22:46 | #39

    “Hey look, I invented a panel that turns sunlight into electricity and does so at a lower cost than grid electricity. If we electrified transport, Australia’s roof area would be sufficient to power the entire country.”

    “WAAAHHH! I don’t like it! Make me something that runs off water!”

  40. BilB
    October 15th, 2012 at 09:51 | #40

    Area of Australia = 1.88 billion acres

    or

    85 acres per person.

    Every person in Australia could have their own 3 megawatt wind turbine and could easily be far enough form it to never hear it operating.

  41. BilB
    October 15th, 2012 at 10:26 | #41

    I wonder if Lance Armstrong considers himself to be a Libertarian.

    He certainly qualifies.

  42. Ikonoclast
    October 15th, 2012 at 10:54 | #42

    @Chris Warren

    River estuaries are very limited and ecologically delicate areas. Putting large, industrial sized osmotic generators in estuaries would completely change the ecology of the ocean-riparian boundary and associated littoral zones. I cannot imagine that this form of generation could be any more than niche level production, just like river turbines. If I look at a an Atlas sized world map from a metre away I can see, even on that scale, large deserts and arid zones but I can’t see river estuaries. This simple test tells me there is far more area available for solar power, probably by several orders of magnitude at least.

  43. October 15th, 2012 at 12:08 | #43

    I just read that because of reduced demand due to rooftop solar and improved efficiency, Queensland’s Tarong power station is mothballing half of its 1,400 megawatt capacity. So coal power capacity that has been shut down and not replaced in the last two or three years include half of Tarong (700 megawatts), Playford B (250 megawatts), Stanwell B (125 megawatts), and Munmorrah (600 megawatts), for a total of 1,675 megawatts. And if you want to throw in half of Northern power station’s capacity as it now only operates 6 months a year, that brings it to 1,935 megawatts, or almost two gigawatts of coal power.

  44. rog
    October 15th, 2012 at 16:41 | #44

    @Ronald Brak Those are remarkable figures – has the reduction in consumption been determined as due to rooftop solar or other factors, like improved infrastructure?

  45. BilB
    October 15th, 2012 at 17:16 | #45

    rog, my reading of RB’s comment tells me that

    “because of…….. reduced demand due to rooftop solar….. and …….improved efficiency….”

    ie, the change was due to solar……and…….efficiency. Not solar …..or ….something else.

    I think that it was pretty clear.

  46. October 15th, 2012 at 17:22 | #46

    Demand is far below what was predicted due to rooftop solar, improved efficiency, decent weather, and increased grid electricity prices. And in more or less that order, I would guess. Obviously solar is resposible for a big chunk of reduced demand, as the country will have close to two gigawatts of it installed by the end of the year. This means that on a sunny day Australia’s PV could supply as many megawatts as the closed down coal plants could generate.

  47. October 15th, 2012 at 17:30 | #47

    Sorry, I wrote Stanwell B when I should have written Swanbank B. There’s no Stanwell B power plant. It was operated by Stanwell.

  48. rog
    October 16th, 2012 at 14:20 | #48

    So of the four factors listed as responsible for a drop in demand two are quite separate from solar ie improved efficiency and increased grid prices. These two are linked, improved efficiency came at a cost which was passed onto the user.

    What is apparent from following graphs is that solar has eaten into peak demand which is where the conventional generators make their money.

    http://reneweconomy.com.au/2012/whos-afraid-of-solar-pv-38844

  49. October 16th, 2012 at 14:54 | #49

    Rog, the improved efficiency is at the consumer end of things. More efficient water heating, lighting, a massive drop in HD TV electricity consumption, and so on.

  50. rog
    October 16th, 2012 at 16:00 | #50

    There’s no doubt solar is both disruptive and sustainable but not without it’s own issues, like quality and price.

    http://www.climatespectator.com.au/commentary/solars-elephant-room

  51. Fran Barlow
    October 16th, 2012 at 16:17 | #51

    In other good news Denmark has apparently reached its 2020 target for solar 200MW.

    http://beforeitsnews.com/environment/2012/09/denmark-reaches-2020-goal-for-solar-energy-8-years-in-advance-2449076.html

    Apparently it is also now producing 40% of its energy from renewables and aims to produce 50% of its energy from wind by 2020.

    Denmark is a net electricity exporter.

    All good …

  52. October 16th, 2012 at 16:36 | #52

    Considering that point of use solar is the cheapest source of electricity available to Australian consumers I wouldn’t exactly say that price is an issue that’s preventing its adoption. And apparently we may see a thirty percent decline in solar panel prices next year. If only every source of electricity had these sorts of cost issues. And as for quality, well, there’s silicon PV still operating after 40 years without any maintenance, which is something that coal or gas plants really can’t manage, so that doesn’t seem to be a huge issue either. Now of course the lower the price the better and the higher the quality the better, but when compared to every other source of electricity, solar PV seems to do pretty well in those two areas.

  53. Jim Rose
    October 16th, 2012 at 17:06 | #53

    Fran, There are more than four thousand onshore turbines – two-thirds more than Britain – in a country a fifth the size. Nowhere else has more turbines per head,

    Thanks in part to the wind farm subsidies, Danes pay some of Europe’s highest energy tariffs.

    The key point is most of that wind driven electricity cannot actually be used in Denmark.

    Power companies have to generate it at the moment you need to use it. Wind’s key disadvantage – in Denmark, as elsewhere – is its unpredictability and uncontrollability.

    Most of the wind electricity Denmark generates has to be exported to Germany, to balance the fluctuations in that country’s own wind carpet, or to Sweden and Norway, whose entire power system is hydroelectric, and where it can be stored. Hydro is carbon neutral so one green energy is crowding out another

    The devil is in the details. See http://www.telegraph.co.uk/news/worldnews/europe/denmark/7996606/An-ill-wind-blows-for-Denmarks-green-energy-revolution.html

  54. October 16th, 2012 at 19:23 | #54

    It appears the stupidity is also in the details. With regards to the article Jim linked to, I wonder if the author, Andrew Gilligan, thinks that is is okay for Europe to share a currency but not electricity? Does he seriously think all the countries of Europe should have their own individual electricty grids? And I’m even more amazed that someone would decide they were qualified to write an article for a newspaper about electricity generation when they don’t know that hydropower is dispatchable. Which means it is complementary with wind power. That means they work well together. How could anyone think they crowd each other out? Does he think the Scandinavians just flush water out of their hydropower dams without generating electricity from it for the hell of it when the wind blows in Denmark? You’d think he’d spend a few minutes thinking it through before writing an article for a newspaper about it, wouldn’t you? But you know, it’s not really possible to honestly make these sorts of mistakes. Sure, maybe he was honestly misinformed, but I think that if he was that gullible he’d be too busy attempting to charge people tolls to cross various bridges he is under the impression he owns to write for newspapers.

    Now I don’t know how Denmark funds its generating infrastructure, but I do know that wind turbines are generally built where electricity is expensive. If one spends a little time to think it through, one will see why that’s the case. Where would you make the most money building a wind turbine? Where electricity prices are low, or where electricity prices are high? That’s why South Australia has a lot of wind power, because it is the state with the highest electricity prices. Sorry, was the state with the highest electricity prices. They’ve gone down. I’m getting a 8.1% cut in what I pay per kilowatt-hour starting next year thanks to wind and solar pushing down electricity prices in South Australia.

  55. Jim Rose
    October 16th, 2012 at 19:37 | #55

    @Ronald Brak
    wind power cannot operate as base load capacity. A key grid ingredient is dependability. Wind does not have this.

  56. October 16th, 2012 at 20:32 | #56

    Erm, yeah, that’s because the wind doesn’t blow at a constant rate all the time. If you ever meet anyone who does think the wind blows at a constant rate all the time I suggest you make them go sit outside or open their doors and windows or something.

    Now just in case you haven’t been paying attention, I’ll mention that a week or so ago South Australia had no operating baseload generating capacity and we did not miss it. We shut it all down for a few months on account of wind and solar pushing down electricity prices and the carbon tax pushing the cost of generating electricity from fossil fuels up.

  57. October 17th, 2012 at 13:36 | #57

    And today I read that another 360 megawatts of Australian coal capacity has been shut down. This time a brown coal unit at Yallourn power station in Victoria’s Latrobe valley. So much for paying them to shut down, they’re doing it on their own.

Comments are closed.