Rooftop solar may be ‘sleeping giant’ of Australian politics

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Three key issues may make rooftop solar the sleeping giant of Australian politics, with tens of thousands of households affected by low tariffs for exports, and a pushback on connections by utilities. This will be big issue in three big eastern states.

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The Greens have launched a new campaign to make rooftop solar a key election issue in the Victorian state poll later this year, describing it as a potential “sleeping giant” in Australian politics

solar unsw1The launch of the Fair Go for Solar Saver campaign intends to tap into three key issues that have so far been ignored by the mainstream parties – the right to connect, the right to install a decent sized system, and to add to it, and the right to obtain a fair tariff for rooftop solar exports back to the grid.

The Greens have been buoyed by the recent success of the Vote Solar campaign from the Australian Solar Council in last week’s Senate re-run in Western Australia. They say that parts of the significant swing to Scott Ludlam can be sourced to areas where rooftop solar is an issue.

The Greens have been the first party to try to tap into the issue of rooftop solar – which now sits on more than 2 million homes (1.2 million solar PV, 800,000 solar hot water) in Australia. Victoria has more than 200,000 of these solar PV homes, hosting more than 540MW of capacity, and within two years more than half of these homes will be receiving little or no money for the power they export to the grid. In some key electorates, in the north-west regional areas and even within the Melbourne mortgage belt, the level of “solar penetration” is nearly 20 per cent.

greg barber
Greg Barber

“Rooftop solar is a sleeping giant in Australian politics … but no one has worked out how to capture it yet,” Greg Barber, the leader of the Greens in Victoria, told RenewEconomy.

But the touchstone may be over the right to connect, expand, and to get fair tariffs. Barber – and the solar industry more broadly – cite numerous instances where distributors such as Powercorp have been either refusing connections or forcing applicants, both households and commercial businesses, to downsize their planned rooftop arrays.

Powercorp and other distributors cite voltage issues as the main reason, but the solar industry rejects this. Similar stories, including demands for big connection fees and costly appeals process, are widespread in NSW and Queensland.

The Greens – and the solar industry, for that matter – think that a crunch point will emerge in 2016, when significant numbers of Victorian households lose their interim 25c/kWh tariffs for exports. At that point, Barber says, more than half the 207,000 households in Victoria will be offered only 8c/kWh.

It is the Greens’ intention to make this an issue in the 2014 poll. They want to enshrine the right to connect and for 1:1 net tariff for rooftop solar. That idea is likely to be fiercely fought by electricity retailers, generators and network operators.

A similar situation will emerge in NSW, where several hundred thousand households on the even more generous 60c/kWh gross tariff (the rate is paid for all electricity produced from the panels, not just from the exports) will find that tariff ending and be faced with a regime where no payment is mandated.

“People are very cranky over the idea that the utilities are paying them just 8c/kWh, yet will sell back the electricity at four times the price a few minutes later,” said Stephen Ingrouille, founder and CEO of Going Solar.

“It’s a comment we hear all the time,” Ingrouille said. “The householders recognise that solar output is valuable during the peak periods, and they know that the utilities are doing well out of it. Unless the utilities start to change their tune rapidly, they will get left behind, because the solar technology is moving so fast.”

The “fair value” of solar is a question that is challenging utilities, the solar industry and households across the world. As we wrote last month, there is a huge difference between the way solar is valued in the US, and how it is valued in Australia.

Major studies from Australia’s CSIRO, the Rocky Mountains Institute in the US, and investment banks Morgan Stanley and Citigroup, suggest that unless households are offered a decent rate of return, then the so-called electricity market “death spiral” will simply be accelerated.

No one really thinks that mass disconnections from the grid is the most efficient outcome, but it is exactly what is predicted to happen – even by the (more forward thinking) utilities themselves – unless the utilities get their pricing right.

The continuing popularity of rooftop solar – despite the removal of feed-in tariffs – has surprised the incumbent utilities industry. More than 43,000 homes have added solar to their rooftops in Victoria since the tariff was slashed to 8c/kWh, defying expectations. That accounts for one-third of the total capacity, due to the fact that households are now installing large systems as the cost of solar falls, and retail electricity prices rise.

More than one quarter of the 800MW installed in the Energex region in south-east Queensland is on the 8c/kWh tariff (soon to be abolished), and households are applying at a rate of 4,000 homes a month. In Western Australia and South Australia, applications are still flowing in at more than 2,000 a month.

Barber says the Greens will also propose a new “clean energy fund” that will facilitate solar leasing and easier access to solar for homes on low incomes, or in rental properties. It could be based on a similar model adopted by the Darebin Council in the inner north of Melbourne, which is offering “zero-down” installations to local pensioners.

“In the past we used to subsidise solar for the environmental benefits, but now we have to make sure that households are paid a fair price, otherwise they will add batteries to their arrays and disconnect,” Barber says.

“There are obvious benefits to having people remain connected to the grid. It avoids the death spiral …. But we have to stop the sheer bastardry of the utilities that prevent people connecting solar.”

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  1. Chris Drongers 5 years ago

    The Greens are on a winner.
    Fears that the current conservative governments are locking Australia into a high carbon energy system in a world that needs to learn how to, and invest in, low carbon energy to avoid enormous climate change disruption, is growing. The historical alternative party is in disarray.
    The Canberra government still has no consistent statements about how Direct Action will work, about the place of Australia’s coal in future climate discussions or even a definitive statement that anthropogenic climate change is a problem to be tackled, about the process of incorporating voluntary distributed generation and future self-funded storage, into electricity networks without destroying the sunk value in the networks or damaging their functioning and about how those without the options for rooftop solar can participate in the industry and benefits.Review after review look more like excuses for delaying decisions or to come up with a pro-coal answer.
    A party with clear purpose on AGW and that espouses a coherent plan for the future based on the science summarised in the IPCC reports will gather up many disillusioned voters. (Even if unemployment goes to 10% and job security favours voting for security, 90% of workers will still have jobs and be freer to vote).

  2. madankerr 5 years ago

    This sounded good until I read that the Greens want a 1-for-1 tariff.

    Then I rolled over and cried.

    Once again the Greens show their naivety about the way the world works. Do they really not understand the difference between retail and wholesale pricing? Why would electricity retailers pay full retail rates for the PV they buy from rooftop solar owners? Last year, they purchased power from major generators for an average wholesale price of 6-7c/kWh. Then they paid network costs. Then they added a bit for their own costs before selling it at retail rates.

    Why would they pay full retail price for power from solar rooftops?

    The bloody Greens! They constantly raise my hopes and then dash them.

    • RobS 5 years ago

      It is clearly you who does not understand how the electricity market works, there is no such as a “wholesale price” there is a national electricity market which sells power in 30 min blocks, in the middle of the day at peak demand this price frequently goes to 20-30c/Kwh and on peak demand days a few times a year it goes as high as $12/Kwh, it just happens that these times are almost exactly when rooftop solar is producing at its peak output too. Therefore the utilities are buying power often far far cheaper from rooftops in the middle of the day even if they have to pay the retail tariff for it.

      • madankerr 5 years ago

        Hi Rob,

        I do understand that wholesale rates vary according to time-blocks. I quoted the national average for simplicity (averages, as I’m sure you know include both peaks and troughs). You say that the price frequently goes to 20-30c/Kwh and on peak demand days a few times a year it goes as high as $12/Kwh. I wonder what the day-time average is? You’re quoting the highs – what are the lows for this time period and what is the average?

        I’m open to someone working out the effective value (wholesale plus
        network costs) for PV exports based on time of production. I bet it’s
        still below the 1-for-1 retail rate.

        IPART notes that the retailer share of electricity costs is 15%, so perhaps a ‘fair’ price for solar = retail minus 15% for the retailer, minus the proportion incurred by govt green schemes – from memory IPART puts this at 15% of the bill.

        Even in that case, the Greens call for 1-for-1 FITs is naive.

        • Tyger Tyger 5 years ago

          The average wholesale price for the retailer comes down the more they can iron out the peaks. Solar contributes to that presently by providing low – soon to be, thanks to ideologically-driven, head in the sand b/s – even lower-cost peak-load power.
          If people start taking their solar off-grid, the retailer has to get that peak-load power from another, far more expensive source, without reducing the peak-load one iota, as solar houses that are feeding into the grid are producing a surplus to their requirements and obviously making no demand on the grid at the time. Just going on the average price mis-states the value of peak-load solar. One-to-one is a more than fair deal for the retailer.

          • madankerr 5 years ago

            The Clean Energy Council disagrees with you. They are not asking for 1:1 tariff – see their submission to the current
            IPART review of electricity prices. To quote:

            “Australia’s solar
            industry does not seek a return to the days of 1:1 feed-in tariffs. All we seek is the right to compete at a fair price. Competing at a fair price means that retailers should pay a benefit-reflective feed-in tariff. A benefit reflective feed-in tariff would be:
             technology-neutral;
             time-varying and would include a critical peak payment; and
             (ideally) location-specific.”

          • Tyger Tyger 5 years ago

            Geez mate. How many times do you have to say that? I get it! I get it! “The Clean Energy Council blah blah blah… I’m right, you’re wrong! Nyah nyah.”
            I disagree. Do you see how that works? I think, given solar is perfect for ironing out daytime peaks, the fact it’s emission free and the right to a fair ROI as Chris Ryan points out above, makes 1:1 a fair price and will be voting for The Greens as a result – ok! You stick with the dinosaur parties.
            Meanwhile, let us know how you feel about the US$523bn in fossil fuel subsidies shelled out by governments worldwide in 2011 – more than six times that given to renewables. (Source: IEA) That would be the “how the world works” the Greens are so naive about. Mustn’t challenge that whatever we do.

          • madankerr 5 years ago

            Hi Tyger, I think we have a lot in common. I totally agree with respect to fossil fuel subsidies, and I’ve been more than disappointed with both ALP and LNP.

            I applaud the Greens for giving us the Clean Energy Legislation (Gillard certainly wouldn’t have done it if the Greens hadn’t been able to hold her feet to the fire). The Clean Energy Legislation was well-designed and comprehensive – I’m sure it will be a model for other countries. And I’m pretty sure we’ll get most of it back again when the wrecking ball has moved on.

            I’m comfy disagreeing with you with respect to a 1:1 FIT. Lots of people want to see subsidised FITs continue (1:1 FITs need govt subsidy cos retailers can’t survive if they buy something at the same price they sell it for). Lots of people think they’re not needed any more. I’m in the second camp.

            Cheers, mate.

          • Tyger Tyger 5 years ago

            Your comment would be fair enough if it wasn’t for the fact that retailers already often buy power at considerably MORE than they sell it for, as has been pointed out many times in these posts. During peak times, which, as has also been pointed out many times, solar is well placed to service. If you worked out what the peak-load cost would be for the retailers if, just as a thought experiment, all solar houses went off-grid tomorrow, you’d find they’d be much worse off. Let’s get back to what the article says:

            “Major studies from Australia’s CSIRO, the Rocky Mountains Institute in the US, and investment banksMorgan Stanley and Citigroup, suggest that unless households are offered a decent rate of return, then the so-called electricity market “death spiral” will simply be accelerated.
            No one really thinks that mass disconnections from the grid is the most efficient outcome, but it is exactly what is predicted to happen – even by the (more forward thinking) utilities themselves – unless the utilities get their pricing right.”

            I tend to think when Morgan Stanley and Citigroup say things like that, the industry should listen.

            The Greens aren’t perfect – nobody and nothing is. Their failure to pass the ETS, even allowing for Rudd’s shabby treatment of them in the process, was a mistake. It played a big hand in Abbott becoming PM and that’s a disaster for the environment. But I don’t agree with your characterisation of them not understanding “how the world works”. They don’t make any apologies for wanting to change that.

          • Alen 5 years ago

            Seems a simple concept to me, if customers are unhappy then they’ll take their business elsewhere. Until the last few years it has been difficult to apply this idea to the electricity market, but with decent PV prices and battery technologies both being heavily developed and invested in (already growing demand e.g. EV, Japan’s scheme and of course German scheme, which as far as I know it are in large part responsible for the big drop in global PV price) well it doesn’t take a brain surgeon to figure out that if utilities don’t change their approach and start listening to growing number of unhappy customers (I.e. Fair FiT price) they’ll soon have no customers at all. And with solar Leases now available, for those could not previously afford to pay ’15 years’ of electricity upfront, becomes viable.

            Take home message, utilities need to change their model/approach or get left behind and die/ go bankrupt

          • wideEyedPupil 5 years ago

            The ETS was free money to polluters for close to zero improvement on BZU. How could anyone in all conscience vote for that even if it was politically naive about what it might do for MP Abbott several years later? Why don’t you chastise the ALP for not putting up a credible ETS in the first place? Because with Marn Ferguson at the helm of energy and resources policy and his replacement ALP remains a climate change quasi-action party in effect.

          • Tyger Tyger 5 years ago

            wideEyedPupil, I’ve voted Green for 20 years and I’d have thought my mentioning “Rudd’s shabby treatment of them in the [ETS negotiation] process” was hardly a ringing endorsement of the ALP. I have no illusions about the “LNP-lite” party. I’m also aware the proposed ETS was a dud, but it would have formed a politically legitimate base on which to build.
            The fact is, for all that I agree with many of their policies, The Greens are politically naive and too pure by half at times. That they demanded a carbon “tax” from Gillard as a prerequisite for supporting her minority government, despite her pre-election promise not to go down that path in her first term, goes beyond naiveté, borders on stupidity and quite predictably opened the door for Abbott’s very successful election strategy. How is that outcome in any way preferable to where we now find ourselves?

          • Tyger Tyger 5 years ago

            Oops! Bit confusing that last question. I meant of course, how is where we find ourselves in any way preferable to having a working, if as yet second rate, politically legitimate ETS in place?

          • wideEyedPupil 5 years ago

            So if and when the Greens become the dominate progressive party in Australian politics (as the ALP are now openly speculating the danger of in newspapers) will you then admit maybe they aren’t too pure for their own good, or even that they might know more about their political destiny than their many knockers?

          • Tyger Tyger 5 years ago

            wideEyedPupil, you’re preaching to the converted here. As I pointed out above, I’m a longtime Greens supporter. However, that doesn’t blind me to their faults; we all have them.
            The reality is politics is the art of compromise. And at this stage The Greens are not as good at that as they need to be if they are ever to succeed in government, especially given their first go at it would doubtless be in coalition with Labor. Their efforts at co-operation with Labor in the last government, including insisting on a price on carbon despite Gillard’s pre-election commitment not to go there, led to the following results in the 2013 Federal election:

            “There was a nationwide swing of 3.34% against the Greens in the House of Representatives, with their primary vote falling to 8.42%. A little over half a million voters who had supported the Greens at the previous election deserted them.
            Swings were registered against the Greens in every state and territory. Some of the severest were recorded in Green strongholds, such as Tasmania (8.73%) and the ACT (5.95%).
            There was also little joy to be found in the Greens’ Senate vote. Across every state and territory, the Greens’ primary vote took a battering (-4.39%). In Tasmania, the Greens recorded an 8.64% swing against them, while in South Australia its primary vote was almost halved (7.07% in 2013 compared to 13.30% in 2010).”

            (, 9/9/13)

            I fully support an ETS and all efforts to mitigate AGW and voted Green accordingly at the 2010 election, as usual. But they didn’t win, so what next? Revolution? Good luck with that in Australia.
            I also look forward to the day The Greens are the leading progressive voice in Australian politics, as the ALP are no longer progressive except at the margins. I just hope by then The Greens have learnt that once you’re inside the tent pissing out, a completely different approach is required to when you’re outside the tent pissing in.

        • JeffJL 5 years ago

          So the Greens call for a 1:1 tariff and you bag them (and look at a 1:0.7 [15+15%]). Retailers have a 1:0.32 (8c:25c). You are right in the middle.

          Bag the Greens all you want but be equally vicious with the power companies.

          • madankerr 5 years ago

            Hi Jeff, yes the power companies are grasping for as much as they can get. That doesn’t mean the Greens should propose a policy that fails to distinguish between wholesale and retail pricing. This is the sort of policy that relegates the Greens to the lunatic fringe.

            Even major environmental organisations like the Clean Energy Council are not asking for 1:1 tariff – see their submission to the current IPART review of electricity prices. To quote:

            “Australia’s solar industry does not seek a return to the days of 1:1 feed-in tariffs. All we seek is the right to compete at a fair price. Competing at a fair price means that retailers should pay a benefit-reflective feed-in tariff. A benefit reflective feed-in tariff would be:
             technology-neutral;
             time-varying and would include a critical peak payment; and
             (ideally) location-specific.”

          • Paul Wittwer 5 years ago

            There you go again bagging the Greens half cocked. The clean energy council is a business organisation promoting clean energy, not an “environmental organisation” . Their interests and aims are not necessarily the same as the Greens which are an environmental political organisation. There is no need to distinguish between wholesale and retail pricing in a policy for a fair FIT. It’s a Feed In Tariff, simple as that.
            By carelessly throwing around insults like “lunatic fringe” you are not only offending me and many others who post here but you are also casting aspersions on the likes of the Melbourne Energy Institute and BZE from whom the Greens take expert advice.
            Can you provide a reference to any other environmental organisations taking the same position as the CEC?

          • madankerr 5 years ago

            Paul, I respect your defence of the Greens. I often vote Green. I’m sure the they do take advice from BZE and the Melbourne Energy Institute – I take their advice myself.

            Are you suggesting that BZE and the Melbourne Energy Institute recommend a 1:1 FIT? I wasn’t aware of that.

            Solar Citizens is an environmental organisation that endorses the CEC’s submission to IPART where they specifically put aside the 1:1 tariff. There may be others, but you would need to seek that information yourself.

            People who argue for a 1:1 FIT are asking for a govt subsidy. Retailers can’t afford to buy electricity at the same rate as they sell it, so a 1:1 tariff would require govt subsidy.

            Given that solar installations have continued strongly (3-4,000 a month in the larger states) in the past 12 months with FITs in the 8-14c/kWh range, it is likely that subsidised FITs are no longer required in order to sustain the industry.

            I’ll be interested to hear from the Greens why they think that governments should subsidise FITs.

            I’m interested in a fair price for solar because in 2016 when my current contract ends, I’ll look at the cost of battery storage and consider going off-grid. What will I need to stay on-grid? I want a fair price, but I won’t expect a subsidised 1:1 FIT.

            I wonder whether Minnesota-style contracts will be available in Australia by then? They sound interesting.

            BTW – there’s nothing careless in my choice of language. I’m really annoyed with the Greens and disappointed in this bit of their policy. It’s how I feel. Just as your use of ‘bagging’ and ‘half cocked’ reflects your feelings more than it describes my words.

          • Paul Wittwer 5 years ago

            madankerr asked “Are you suggesting that BZE and the Melbourne Energy Institute recommend a 1:1 FIT?”
            No, I am not suggesting that. See my reply to Malcolm above.
            What evidence have you that 1:1 fit requires a govt subsidy and if you have such evidence, see Tyger Tyger’s reply below re fossil fuel subsidies.

          • madankerr 5 years ago

            Hi Paul, Thanks for continuing the conversation.

            Re subsidies for the 1:1 FIT – I just can’t see how a retail organisation can survive if it buys something for a dollar and sells it for a dollar. I know that electricity is more complicated than this cos some retailers are also generators (gentailers). But many aren’t. In QLD for example the generators, network, and retailers are separate bodies. Electricity retailers buy power from the generators and pay a fee to the networks.

            I’m not against subsidies for clean energy – especially in the face of the fossil fuel subsidies. However, it seems to me that solar PV has passed the point of needing subsidised FITs. They’ve been phased out in QLD, NSW, SA and VIC and the uptake of solar PV has continued to be unexpectedly strong – 3-4,000 a month in QLD for example.

            I support the RET-funded subsidies to the purchase cost of new PV.

            Rather than arguing for a 1:1 FIT, I’d like to see a campaign to reduce fossil fuel subsidies. It would be better to see less subsidy overall rather than adding a ‘good’ subsidy to counterbalance a ‘bad’ one. I’d start with scrapping the diesel rebate for miners. I’ve yet to see any reason (good or bad) for keeping it.

          • Paul Wittwer 5 years ago

            Ah, I think I see the problem. The 1:1 FIT is not a situation of retailers buying for a dollar and selling for a dollar. Most of the time they buy for less than 5c and sell for 30c and some times they buy for $12.00 and sell for 30c.
            The point is that at times when retailers would be buying wholesale power for prices well in excess of the basic 30c retail from other generators, they are also obtaining solar power from households and only paying 8c for it.
            I’m with you on ending fossil fuel subsidies.

    • Paul Wittwer 5 years ago

      A Melbourne University study puts the real value of solar electricity between 40 and 60 cents, taking into account aspects such as reducing electricity distribution infrastructure costs and time of generation.
      Those in the industry simply want a 1:1 feed in tariff rate implemented across Australia, whereby solar households receive the market rate for the surplus electricity they export to the mains grid.
      Clearly the wholesale price you quoted is averaged across all demand periods and doesn’t reflect the value of the power delivered by solar when it is generating.
      Perhaps next time you want to badmouth the Greens, or anyone for that matter, you should first check the validity of your assumptions, or better still don’t bloody well make any in the first place.

      • madankerr 5 years ago

        Hi Paul, I’d be interested to read the Melbourne University study. Do you have a reference or a link?

        What do you mean by “the market rate”? Do you mean retail or wholesale rate?

        The average wholesale rate I quoted includes the peak rates that spike during specific events like heatwaves.

        I’m open to someone working out the effective value (wholesale plus network costs) for PV exports based on time of production. I bet it’s still below the 1-for-1 retail rate.

      • Malcolm Scott 5 years ago

        Paul, I too was surprised by the Greens proposal for 1:1 net FIT (I presume in Victoria that means on 30 min intervals for off-peak, shoulder, and peak tariff).
        I too was discouraged by this 1:1 FIT policy thinking that it was over reaching on credibility.

        Perhaps I should spend more time reading the net FIT debate in the US, but in the meantime can you provide a link to that Melb Uni study you cite?

        Many thanks

  3. RobS 5 years ago

    Ideologically the liberal party is behaving and probably truly believes cocooned in their ivory tower that solar and other renewables remain the domain of fringe dwellers and unwashed hippies. I think it has completely eluded them that over 25% of the Australian voting population now live in a home with solar panels. You simply can’t disenfranchise that many people without repercussions.

    • Alen 5 years ago

      Ah, but this would require some logical reasoning, and Abbott’s suggestion that the WA outcome was another clear indication that voters want the carbon tax gone rather than the more logical view from the result–> that people want more clean energy (high swing against both major parties that have inadequate RE policy), well Abbott just seems to be lacking logical deduction skills in this department. I’m very curious to see the how the Qld campaign and election will go. The tariff has already been slashed to 8c and is soon to be wiped completely, that’s 40,000 potentially very unhappy voters (the biki laws, doctor pay dispute or the continuous clashes with the Law community won’t help Newman win back much support either from voter)

  4. chris ryan 5 years ago

    I think that discussing the value of exported household PV electricity
    within the distortions of the currently constructed market is very
    problematic. One thing that is being ignored is that those 1.2m rooftop
    PV systems represent – roughly – around $5b invested in the electricity
    production system (based on a very rough average cost to those
    households) that has occurred outside of the usual capital markets and
    the investment plans of the existing producers. This can be viewed as a
    large community owned generating plant. Any value paid for the
    electricity from those PV systems should take into account the capital
    investment in that generation (an ROI) as well as the fluctuating value
    of the half hourly wholesale price + the value of the avoided demand
    which would significantly reduce the wholesale price for electricity
    during – for example – the peak hot (airconditioning) days.

    • Tyger Tyger 5 years ago


      The peak-load benefit to the retailers is enormous during the working week in particular when it’s hot, because most people are at work – with the air-con on – while the only demand in their solar-powered houses is to run a fridge and a few other odds and sods, the rest going to the grid.

  5. Motorshack 5 years ago

    My question for all of you is this: what would happen if essentially everyone had the ability to generate their own electricity at the lowest possible cost?

    Answer: there would be no market for electricity.

    That will never quite happen in the real world, of course, because not everyone is perfectly free to choose to buy from the lowest-cost source. However, we might come rather close to that situation, and then there would be a very small residual market for trading electricity.

    More to the point, the prices in that market would be dominated by the low costs enjoyed by the vast majority who were outside the market altogether.

    That is to say, if the market price strayed too far from the low costs enjoyed by those who produced their own electricity, then it would just cause someone to start selling some of their cheap electrons into the overheated market. And that would be the end of the price spike.

    The flaw in this whole debate is the unexamined assumption that market conditions today are permanent, when in fact they are highly transitional.

    In another decade or two the cost for everyone will be substantially lower than it is today, and the remaining markets will then have far less horse-trading of any kind.

    • madankerr 5 years ago

      Hi Motorshack, I am glad that the Greens take environmental issues seriously, and I think it is great that they have a Solar Policy. As suggested, it may be an opportunity to gather support from people who live in the 2 million solar homes. Nevertheless, I continue to feel that their demand for a 1:1 tariff oversteps the mark. Note that the Clean Energy Council says “Australia’s solar industry does not seek a return to the days of 1:1 feed-in tariffs. All we seek is the right to compete at a fair price. Competing at a fair price means that retailers should pay a benefit-reflective feed-in tariff.”

      I’d love to see Abbott held to account for the pre-election promise of 1 million new solar homes. If he put some runs on the board to achieve this, he might give the Greens a run for their money with respect to solar. Then we’d see two political parties competing to expand/support solar. Wouldn’t that be great!

      That said, I think there’s about zero chance of Abbott doing that. He’s letting that promise disappear into the rear vision mirror.

      • Motorshack 5 years ago

        Fair enough. In the short run there is certainly some room for debate about just how big a subsidy is still necessary for solar PV, and for just what reasons.

        My personal approach is to stay off the grid altogether, and to focus on making the cost of my system (including storage) so low that I can comfortably ignore the whole question of markets.

        The trick to making storage cost-effective at today’s prices is to use a two-axis tracking mount, which improves the yield of the system by about 40%. Commercial mounts are too expensive, so their cost wipes out the advantage of the greater yield. However, a solid DIY mount only adds about 10% to the system cost, leaving enough extra yield to pay for most of the cost of storage.

        As I said in my initial comment, the long-term benefit of all this is low prices for electricity, so, as long as my own system is doing that for me, starting immediately, I am largely content to sit back and watch everyone else yanking each other’s hair out by the roots. I simply do not have a dog in that fight.

        Bear in mind also that I live in an area (New England, USA) where electricity still only costs 17 cents per kw-hour, yet I can make solar with storage pay nicely. If the power company were charging what you folks pay in Australia, I would be laughing myself silly at anyone who stayed on the grid.

        More than that, I would be thinking hard about getting into the market for sexual lubricants. Clearly there is money to be made in that.

        • Chris Fraser 5 years ago

          You guys – does Disqus allow hypertext markup language to set paragraph spaces ? impressive.

          • Motorshack 5 years ago

            If you are talking about the blank lines separating my paragraphs, that is not HTML. It’s just an extra carriage return in otherwise unformatted text.

            Also, interesting to see that it is the formatting of my comment, rather than the content that draws a reaction. I’ll spare myself the effort next time, no doubt to great relief all round.

          • Farmer Dave 5 years ago

            Don’t spare the effort, please Motorshack. I enjoy your comments and hearing your perspective from the US. Your suggested alternative investment strategy in your second comment of this thread gave me a good laugh!

            I’m impressed by the low cost of your offgrid system. Can you give us some basic parameters, such as panel output power, battery storage capacity and days autonomy, please?

          • Motorshack 5 years ago

            Glad you found my other comment funny, and nice of you to say so.

            Anyway, getting best value from a solar PV system is much more a question of good financial management than it is a technical question. Here’s my short list of do’s and don’t’s.

            1) Do your homework, so you use the most cost-effective design.

            2) Make your use of electricity as efficient as possible.

            3) Pay cash for the components, so you don’t pay interest.

            4) Do your own work, so you don’t pay for outside labor.

            5) Use a DIY two-axis tracking mount to increase the system yield by 40%, while only increasing costs by 10%.

            6) Stay off-grid to avoid the cost, complexity, and risk of grid-ties.

            7) Buy a small gasoline generator, strictly for emergency back-up.

            Obviously, not everyone can make use of every single one of these tactics, but as you go through the list you will get a sense of the unexamined overhead in most of the available commercial offerings.

            In general, paying gobs of interest, on an oversized system, that fails to capture 40% of the available energy, tends to be a solid loser, even after the price drops of the last few years. So, avoiding those unnecessary costs is clearly the way to go.

          • wideEyedPupil 5 years ago

            4) Do your own work, so you don’t pay for outside labor.

            What parts of a rooftop system install can you legally do yourself and which must be contracted licenced professional. i.e. 240VAC connections must be by a licenced electrician, what else?

            5) Use a DIY two-axis tracking mount to increase the system yield by 40%, while only increasing costs by 10%.

            Put up or shut up, as they say. Not meaning to be rude but just trawled thru your discussion with John and until you demonstrate very low costs for dual, or even single in some locations, axis tracking it’s a big distraction. As you say the idea is not exactly new but no solar advocates I’m aware of are in agreement with you. ATA for example. Why isn’t their magazine full of DIY dual tracking systems if the benefits are there. They have DIY projects for everything else.

            Also I have a series of flat roofs, with strong surfaces just like a room floor with decking/bitumen on top. I’m wondering how many panels you are placing on a dual axis tracker and what spacing you need for the next tracker to avoid shadow loss.

          • Motorshack 5 years ago

            I have answered most of your questions in other posts, but let me summarize, and add a few details.

            When I say DIY, I do not mean to violate the building code. It is there for a good reason. My point is rather that much of the work in any construction project is simple, but tedious stuff that any normal person could do for himself. Also, there are many situations in which the building code does not apply, because the public is not at risk.

            When I remodeled an apartment house some years ago, for example, I had to hire a licensed electrician, because it was a commercial building. However, he agreed to let me do the job that his paid helper would normally have done, thus saving me several hundred dollars.

            Now, why are there not more trackers out there?

            The problem is not the benefits. They are quite real.

            The problem is that it is tricky to design a tracker that is strong enough without being hugely massive. It happens that I have a lot of sailing experience, so for me it was fairly obvious how to handle tons of wind force with a very light rig.

            Once you see how it is done, you will realize that it is almost stupidly simple, but without seeing it you might never think of it. I just happened to have the right combination of sailing experience and mathematical background (actually, also from navigation work). So, I guess I was the lucky one to have the creative spark drop onto dry enough mental tinder.

            Finally, shadowing could well be a problem, because at full tilt these things do have a big shadow, just like the sail on a boat. You will have to plan carefully for that. No doubt.

            However, my concern is mostly for people in the Third World, who will be trying to get the most from the few panels they can afford to buy. If they can afford acres of panels then they will not be the folks I am worried about.

            My estimate for the costs – for the tracker itself – is a couple of hundred dollars, and that is using all-new material, and with automated tracking. The framework itself is something on the order of a hundred dollars worth of lumber, wire rope, and hardware. The sensor and linear actuator are available for about a hundred dollars total. It all runs off a tiny amount of 12-volt power. In production it will be self-powered from the panels mounted on it.

            In contrast, the usual massive, “gold-plated”, single-column design is ten to fifteen times as expensive.

          • wideEyedPupil 5 years ago

            Yes. I you go to this page at Discus then you will see which HTML tags are acceptable and which are unavailable not.

          • Chris Fraser 5 years ago

            Thanks wEP. i must try some of that.

          • wideEyedPupil 5 years ago

            You can insert images using the icon in bottom left corner below the text field of disqus panel.

        • Tyger Tyger 5 years ago

          “Clearly there is money to be made in that, given the way that your power companies and their pet politicians are presently treating you.”

          Without disagreeing with most of what you say, Motorshack – and not to defend either power companies or pollies! – Australia has some serious geographical and demographic issues to deal with in delivering services and infrastructure. We’re the size of the continental U.S. yet have about 90% of the population living in urban areas dotted around the coast, most of those in just three cities – Sydney, Melbourne and Brisbane. As a result, there’s considerable subsidisation of rural areas by urban centres, making just about everything more expensive.
          All of course which – you’d think – should make us world leaders in renewables, islanded systems and the like. That we’re not brings us back to our power companies and pollies, and a strange hesitancy we’ve always had about taking the lead in much of anything.

          • Motorshack 5 years ago

            Right, which is why the key part of my comment is that you can go off-grid right now by looking at what a cost-effective tracking mount does to the economics of a solar PV system.

            Most writers seem to dismiss this option without any sort of serious investigation or analysis, so very few people are presently getting that advantage.

            Yet, despite the inattention of the masses, the advantage is quite real. And it is potentially revolutionary, as far as I can see.

            So, I trust you will pardon me if I get disgusted when people spend time reacting to the formatting of my comments instead of the content.

            Or, in your case, telling me that Australians are too confused to pick up money that is sitting there for the taking.

          • Tyger Tyger 5 years ago

            So you want me to pardon you for pretty much agreeing with what you said?

            “All of course which – you’d think – should make us world leaders in renewables, islanded systems and the like. That we’re not brings us back to our power companies and pollies, and a strange hesitancy we’ve always had about taking the lead in much of anything.”

            Ok, pardon you.

          • Motorshack 5 years ago

            Sorry. I was not trying to be snarky, but rather to tone down my earlier level of sarcasm, by explaining what provokes it. I did see that you and I were generally in agreement. Unfortunately the written word does not represent tone of voice, which would have been useful in this case.

          • Tyger Tyger 5 years ago

            No dramas, mate.

          • Chris Fraser 5 years ago

            I think Motorshack was discussing my query about allowed uses of hyptertext in blogpost comments. It’s a genuine enquiry and may not be allowable or be different for different platforms – but – others may extract unintended meanings from it.

          • John Silvester 5 years ago

            To suggest that “serious investigation or analysis” into PV trackers is not correct. Research in the 90’s showed that the amount of energy gained diminishes the closer the system is to the equator. So any advantage to using trackers is completely dependant on the location of the system and the cost of the tracking system. So it may be that in Tasmania and Victoria, if the cost tracking systems are sufficiently low, there may be case for adding tracking. I know in Queensland, even when solar panels were much more expensive, adding extra panels was cheaper than using trackers. With the large fall in the cost of panels the economics for trackers will have deteriorated, unless the cost of tracking systems has fallen faster.

          • Motorshack 5 years ago

            Sorry, but latitude has nothing to do with it. Everywhere in the world the sun travels from east to west through the course of the day, and from north to south through the course of the year.

            The problem here is that most people do not apparently understand the astronomy and geometry involved. My personal advantage is that I once spent some time designing electronic navigation systems, so I had a need to master these details at a professional level of expertise.

            Also, a tracker that can hold a kilowatt’s worth of panels can still be built for less than the price of one 250 watt panel, but it will add about 400 watts to the yield.

            The more interesting point is that every panel you do choose to add will give you 40% more power, for a much smaller increase in proportional cost. In other words, it can scale well.

            In particular, every solar PV system needs rack mounting of some kind for the panels, so the real cost comparison is between the cost of static versus tracking mounts. In the end there is rather little structural difference, so most of the cost difference lies in some now-cheap electronics and actuators.

            The point is that static mounting is not free, but many of the published cost comparisons seem to neglect that fact.

            So, I stand by my claims.

          • John Silvester 5 years ago

            The modelled performance of solar trackers for various locations around Australia is shown below. The modelling has been undertaken using the PVWatts Performance Calculator for Grid-Connected PV Systems designed by the Renewable Resource Data Center, part of the US National Renewable Energy Laboratory. The figures below take all of the necessary factors into account, including meteorological factors such as average cloud cover and temperature loss factors.

            As the table shows below, installing a single-axis solar tracker will boost your energy output in Sydney over the year by 20%, 25% for a dual-axis tracker.
            Yearly average increase in energy output (kWh) due to single-axis and double-axis solar PV tracking systems
            City Single-axis tracker Dual-axis tracker
            Darwin 20% 25%
            Port Hedland 29% 36%
            Brisbane 21% 25%
            Perth 26% 32%
            Sydney 20% 25%
            Adelaide 23% 28%
            Canberra 25% 32%
            Melbourne 19% 23%

            Yearly average increase in energy output (kWh/year for a 1kW system) for a fixed mount, single-axis and double-axis solar PV system

          • Motorshack 5 years ago

            I’ve used PV Watts a few times, most recently just the other day, and I don’t recall any way to enter the actual costs of either static or tracking mounts. You just tell it which type you are using, and the program supplies estimates of the costs for the system as a whole.

            So, I fail to see how modeling based on PV Watts will be able to prove which mount is more cost-effective. The monetary values we want to discover are apparently already hard-coded into the program by the designer of the software.

            As for the figures on percentage improvement in yield, I am interested in seeing more data, because if the only difference in the modeling of the various mounting options is the geometry, then you would expect to see more consistency in the ratios. So, the fact that they wander so much suggests that either they are not controlling for the other variables very well, or you are not passing on the full results of the modeling.

            Mind you, that last is not at all to suggest that you are being dishonest. What I am saying is that in passing along some key figures, you have not relayed enough to let me check the full model for myself. That’s all.

            Finally, when I say that it is possible to go off-grid today, and that a tracking mount is a key tactical element in my approach, that is not to say that it is the only element. I do a lot of things to get the cost of a system down to something cost-effective, and a tracking mount is necessary, but hardly sufficient.

          • Motorshack 5 years ago

            I also meant to point out that even if the improved yield is only 25% it is still a money-maker, because the added system cost for tracking is less than 10%. So, your numbers hardly ruin my basic argument.

            Keep in mind that the overall strategy here is not to find one single, overwhelming reduction in costs. It is to marshal a whole series of mostly modest reductions, which collectively result in a dramatic reduction in costs.

            That reduction in turn makes it possible to afford battery storage, even at today’s prices, and still pay less than one would by staying on the grid.

            And that changes the whole damned game.

          • John Silvester 5 years ago

            The figures have nothing to do wit cost competitiveness but gains in electrical yield. So cost of trackers is irrelevant. It does take into account more than just latitude by including “all of the necessary factors into account, including meteorological factors such as average cloud cover and temperature loss factors.” So the real world gains are much smaller than your much quoted 40% gains.
            Also, how many people are prepared or even capable to build, maintain and repair a DIY tracking system. This leaves the vast majority of solar customers with commercial tracking systems and the on going maintenance repair costs which for non-DIYs would be high.
            I imagine few people would be prepared to mount tracking systems on the roof of their house though on some commercial buildings where they are out of site this may be less of an issue.

          • Motorshack 5 years ago

            I’m sorry, but gains in electrical yield do lead directly to important gains in the cost-effectiveness of the system. So, that suggestion does nothing to refute my point. Quite the opposite.

            You also keep quoting the assertion that the models in question take “all of the necessary factors into account, including meteorological factors such as average cloud cover and temperature loss factors.” But my question is: just what exactly were those factors, and precisely how were they tied together mathematically in the model? You are asking me to take it on faith that the modeling is valid, and that is not acceptable. You need to come up with more than that.

            Moreover, one of the modeled cities did have an improvement of 36%, so right there that makes the theoretical improvement of 40% rather plausible. So, my precise question is: what accounts for the differences among the various cities?

            There is an implicit suggestion that there is some inefficiency in the other cities, which might conceivably be corrected by custom designs for each different locale. But, until we see the full model, there is no way to guess what might be appropriate.

            As for the alleged technical complexity of a tracking mount, you have no basis yet to form an opinion, because I have not yet supplied that sort of detail. I am generally willing to do that, but these comment threads are already enormously long, and are not, in any case, a very good venue for detailed technical presentations.

            Basically, however, a tracking mount is about as complex as a child’s playground seesaw. It has one electronic sensor to detect the position of the sun, and one actuator to move the rack back and forth around the primary (i.e. east-west) axis. Motion along the secondary (north-south) axis happens only twice a year, and is done in about one minute by hand.

            The sensor costs about forty dollars, and the actuator is about sixty dollars. Bearings are about twenty dollars. The small amount of extra framing required is about fifty dollars, if purchased as new material, and ranges down to nothing if built from recycled scrap, which is quite possible. I designed this for use even in the poorest Third World countries where building from scrap is normal and often absolutely necessary.

            So, in actual fact, a well-designed tracking mount is only slightly more complex than a static mount. It is true that not everyone could build one, but probably anyone who can repair a bicycle could do so. And nearly everyone probably has a friend or relative who could help out with great ease.

            Indeed, YouTube has lots of videos of experimental trackers built for junior high school science fairs. It is almost literally child’s play. Just go to YouTube and enter “solar tracker” in the search field. You will find enough videos to keep you busy for the rest of the day.

            It is also true that ground mounting is preferable, but that also has other significant advantages, such as ease of cleaning and maintenance. Ground mounting is also much safer since no one is at risk of falling off a roof, and a failed mounting is much less likely to drop a heavy load on the people walking below, for the simple reason that normally no one will be underneath the thing.

            Also, active tracking is not the only way to improve the yield of solar PV systems.

            For example, concentrating more light with simple mirrors reportedly yields similar improvements, and with no moving parts at all. However, I have not properly researched that approach as yet, so I am not prepared to defend the idea. For the moment I can only say that there appear to be yet more ways to improve the yield, at least to some degree, and quite possibly to a very substantial degree.

            In short, I’m betting heavily against the current business model of the incumbent electrical utilities. The technology already exists to hit them much harder than they have been to date, and they are barely holding on as it is.

          • John Silvester 5 years ago

            First the cost of the tracker has no bearing on yield at all. The model refers to yield not cost effectiveness.

            Second, the standard roof mount for rooftop solar consists of two aluminium rails a couple of brackets and screws and maybe 30 min of labour. that’s it because the structure already exists. So the cost of the actuator would alone be more than the cost supplying the aluminium framing. Let alone the cost and effort to build footings, mounting a steal post to raise the tracker above the ground/roof, cut and assemble the frame, mount actuator, controller and sensor. So even if all that labour were free, and you got all your materials from a junkyard for the footings, post and framing for free, the cost of the actuator, sensor and controller would still be 2 or 3 times as expensive going to the local solar supplier for a couple of lengths of panel racking frame.

            Claiming a solar tracking system can be built for only 10% more than a fixed system is not credible.

            To suggest modelling from US National Renewable Energy Laboratory (NREL) is not reliable is disingenuous. As for modelling assumptions please take that up with NREL.

          • Motorshack 5 years ago

            Look, you are clearly envisioning the same clunky, overbuilt, overpriced stuff that makes trackers look like a bad idea economically. And I agree,absolutely, that crap will not do the job economically.

            Nor do I give the proverbial rat’s ass about NREL. They are basically in business to give big corporations marketable ideas at taxpayer expense, not to turn on the lights in Third World villages for pennies on the dollar, which is my actual goal.

            There are other structural approaches that are very light, do not require tons of steel and concrete, are in fact quite portable, yet will still hold an array of six or eight panels quite nicely, even in hurricane-force winds.

            It isn’t mass that makes a structure solid. It’s the geometry.

            Just ask Buckminster Fuller, or, better yet, check out one of his geodesic domes.

            The structure I have in mind can be built by people with elementary construction skills, who have nothing but ordinary hand tools, and they can be built from cheap, locally sourced materials.

            Only the electrical components might have to be imported, and even they can be manufactured in any country that has any sort of manufacturing base whatsoever. In other words, maybe not possible in Somalia, but certainly in Egypt or Kenya.

            For that matter, if you were willing to make manual adjustments for about one minute an hour, you could skip the electrical controls altogether, and I have been in places where that would be a very acceptable trade-off.

            Set it up in a school yard, and once or twice an hour the teacher sends out a kid to move the tracker another notch. Kids would volunteer just so they could stretch their legs for a minute.

            Even the bearings, which are the only really precision mechanical component could be cannibalized from used bicycle hubs. And if you were doing the tracking manually you would not really need them. You could get by with a couple of U-bolts that were not quite tightened all the way.

            The reason I mention any of this in this venue is because it would work equally well in the First World, except here folks could easily afford the hundred dollars extra to automate the east-west tracking.

            Unfortunately, a very great many of the people in the rich countries are like you. They apparently cannot consider an alternative approach unless it involves signing a promissory note that will put them deep into debt slavery for the rest of their bloody-minded lives. That is no doubt the unfortunate result of a lifetime of exposure to corporate advertising, but whatever the cause, it is truly pathetic to watch.

            In contrast, I have had many dozens of friends from poor countries, and I have learned to watch very closely how they do things, because most of them appear to have near-genius talent for managing money. They work angles that would never, ever occur to the average American or Australian.

            And what makes them so good? Simple. They had so little to work with that they had no choice but to get good at the management of their resources. We rich folks never had that sort of pressure, as a rule, so most of us are total slobs with our money and other resources.

            So, naturally, you find it incredible when I say what I have about something like tracking mounts. For you, it is literally not possible to believe such ideas, because you have probably been totally brainwashed. To you, and those like you, the only credible explanation is that I must be a liar, or deranged, or quite likely both.

            The point is: that is solely your problem, not mine.

            My life is absolutely chock full of cute ideas like this. Hundreds of them. Which is why, like my Third World friends, I can live exceedingly comfortably on vanishingly small amounts of money. My total income is less than $20K, yet I manage to save about a thousand a month, every month, year after year. Indeed, I don’t even break a sweat.

            Now, go ahead. Tell me I’m not believable, and see how much good it does you.

            Finally, for you more open-minded folks in the crowd, I thank you for an interesting discussion, and I hope that I have given you something interesting, or perhaps even useful, to think about.

          • John Silvester 5 years ago

            I wish you well in bringing your vision to reality.

          • Motorshack 5 years ago

            Very well. Thank-you.

            And, just to clarify, what annoyed me the last go-round was not the near-insult, which I could not care less about, but the creeping sense that you might be deliberately wasting my time out of sheer bloody-mindedness.

            Life is short, I’m not young, and I’m still trying to get some useful things done. If you are not convinced of the utility of my project, or not interested, that’s fine, but you might still have given me some credit for simple sincerity.

            So, now that you are apparently doing just that, I have no complaint.

            Now, that being said, I still think that everyone reading this might give some serious thought to how spoiled we really are in the rich countries. That lifestyle really is wrecking the planet, and really does have a very good chance of killing our grand children. Everyone’s grand children. In every country.

            That is why I, for one, am wracking my brains to find every bit of leverage I can in clean energy systems. Solving that problem alone will not solve our entire set of environmental problems, but it will be a very good first step, and in the Third World it could be a giant first step – provided only that we can think in terms that really are applicable outside our own cozy little niche.

            To quantify that, we need designs that are two to three orders of magnitude – a hundred to a thousand times – more cost-effective than the crap we tolerate in the rich countries.

            That is a huge leap in efficiency, but the interesting thing is that it is often quite manageable – not because we designers are so awfully clever, but because First World efficiency standards are so often grotesquely bad. It often does not take a lot of thought to do a lot better.

            And that is why some of those designs seem at first glance to be so weird. We are simply not used to seeing what truly efficient systems look like. That’s all.

        • Miles Harding 5 years ago

          Good thread, guys. I like this sort of constructive discussion!

          I have a slightly different perspective that avoids most arguments. I was discussing MPPT trackers with a friend who was using marginal cost to decide his options.
          I think the same applies to panel trackers. After any show stopper arguments (space?) are considered, the question can then be: is it more cost effective to install a tracker or some additional panels?
          Latitude is also a factor, the farther from the equator makes a tracker more beneficial, but the marginal cost test will sort this out.

          I note that a lot of installations are now going for east-west facing arrangements, which have a similar effect at the expense of a few extra panels. Also, I have seen a few installations that over-power the inverter, say 7.5kw of panels on a 5kw inverter.

          You’ve given me a couple of ideas:
          first, retrain the Hills hoist as a tracker that also keeps the washing in the shade.
          second, put the tracker on the shady side of the roof to make use of that otherwise unusable section of roof. This should offend the neighbors almost as much as a wind turbine in place of the TV antenna.


          • Motorshack 5 years ago

            I don’t have a picture, much less one up on the web somewhere, but if I did you would easily see why I think you are all missing the point so badly about the price and complexity of tracking mounts. They are ridiculously simple, once you see how a good one actually works.

            Basically I can build an extremely strong mount for about fifty dollars of angle iron, plus a couple of bearings. And there is no reason not to use extremely cheap, recycled material if you happen to have it available.

            Nor is steel the only option. I have seen good mounts built with two-by-fours, and even mud brick could be used for most of the structure. Only the axle and bearings need to be steel, and only the bearings need to be precision machined. Usable bearings can be had from for about ten dollars apiece. Go look up “pillow block bearings” on Amazon, and you will see what I am talking about. Ten bucks.

            Also, the Hills hoist is EXACTLY the wrong idea, but at least I can see where you are going wrong in trying to visualize what I have been talking about.

            In particular, a single, unsupported column would be taken down by the first stiff breeze. It may work well enough for laundry, which hangs statically, and does not resist the wind, but solar panels would act as a rigid sail and put tons of lateral force on the vertical column.

            That is why that style of tracking mount is so expensive. It is a bad design, and the designers throw gobs of money into the structure to solve a problem they could have avoided very easily and cheaply with better geometry.

            Instead, think about those tents they use on Everest that weigh five pounds and are rock solid even in a hundred mile an hour wind. It is not their weight that makes them strong, but rather their geometry.

            Also, guy wires are elements in tension, not compression, and nylon has very high tensile strength for its weight. Steel is nice because is strong in both tension and compression, so relatively light elements, with the right geometry are very strong and rigid, yet also dirt cheap.

            Also, this canard about distance from the Equator is simply wrong. Really wrong.

            I don’t know whose analysis you are all quoting, or what kind of mount they were modeling or testing, but a proper mount – what an astronomer would call an “equatorial” mount – will have exactly the same optical benefit at any latitude, including both the Equator and the poles.

            I say again, exactly the same benefit.

            The reason that you are getting this wrong, is very probably because you are not visualizing the full geometry of the situation correctly. You are visualizing things from a point on the surface of the Earth, but you actually have to look at it from out in space, where you can see the entire Earth, and its full relationship to the Sun. Only then will the geometry of the equatorial mount make sense.

            Indeed, once you see it from the correct point of view, it is a very simple idea, but from the wrong point of view it will be essentially incomprehensible. So, no mystery for me that you are all confused on this point.

            Finally, this supposed trade-off between a tracking mount and more panels is a false dichotomy. Given the very low cost of a well-designed tracking mount, and the very large improvement in yield, a tracking mount is actually quite the no-brainer.

            That is to say, you buy as much in the way of panels and controls as you need or can afford, then you unconditionally mount it on a tracker. There is no reason to avoid doing so. It is too cheap to be a cost problem, and why would you skip the benefit if it costs so little?

            And that is all I will say for the moment. Perhaps, when I have finished my testbed system, can show you all some pictures, and also have solid documentation on the performance, I will find some way to let you all see what I have been doing.

            However, since I am not yet in a position to let you see things so easily, and since my present verbal descriptions are leaving you confused. I will leave off for the moment.

            One last thought.

            My testbed is not original research. Lots of solid academic people all over the world have already built such test systems and published their results.

            What I am doing is the engineering work to make these results easily applicable by even the poorest people in the world.

            That is why I am such an asshole about cost, and also why I tend to laugh hard at the clunky, over-priced designs being sold to rich people with far more money that brains.

            In this world you really do pay for your ignorance, and often you pay in cold cash.

        • wideEyedPupil 5 years ago

          “The trick to making storage cost-effective at today’s prices is to use a two-axis tracking mount, which improves the yield of the system by about 40%”

          Can you link to some more info on this. I have asked this question many times of installers and ATA with regard to a single axis tracking arrangement and the figure I am told is 10% at most improvement, so the material and labour costs for tracking are cancelled out. just buy a few more panels is the response.

          Are you talking about roof mounted dual-axis tracking as DIY. I would love to see something more on that as I’m yet to install solarPV, was hoping Libs would announce a program for low-income earners but doesn’t look like they will do anything on Solar except try and deprive it of oxygen while not picking a fight with 2 existing million owners.

          • Motorshack 5 years ago

            If you have looked at the rest of this discussion, you will see that there are a lot of differing opinions on the subject, and clearly someone is wrong.

            My personal opinion is that typical trackers are very badly designed, and can only stand up to wind loads by being made very massive. So, their cost does overwhelm the value of the extra energy that is produced. That is to say, they produce more energy, but at a very considerable additional cost in material, labor, controls, etc.

            My own approach comes from my experience as an avid amateur sailor, and in particular my design owes a lot to the type of rigging used in sailboats. It is very strong, and very easily controlled, yet the structure is extremely light with respect to the loads being handled. It is not a question of mass, but of clever geometry that balances forces instead of using brute force to oppose them.

            Unfortunately I cannot give you a link to a picture, because I am just now starting construction, and even my drawings are on paper, not in some digital format.

            Now, as to the benefits of a tracking mount:

            Even on the best designed fixed mount a solar panel will be unable to gather more than about 62% of the available energy. This is simple trigonometry and elementary optics, and the problem is simply that the panel is usually pointed, at least partially, in the wrong direction.

            In contrast, a two-axis tracker will make it possible to gather all 100%. Again, the reason is simple. The panel is always pointed straight at the sun.

            So, the ratio is 100/62.5 or 1.6, which is to say the tracker will gather up to 60% more energy than even the best fixed mount system.

            Note that this ratio is not dependent upon the weather or the geographic location. Two trackers, side-by-side, one fixed and one tracking, will have this relative performance ratio.

            Here is one link to an academic experiment with a real tracker, not a software model, and the numbers are very interesting.


            This study actually compares two different methods for improving performance: tracking and concentration with mirrors.

            Nor is this the only thing out there. Lots of people are doing stuff with trackers, and there are quite a lot of ideas about how to build them more cost-effectively. What is not in question, however, is the performance improvement. That is real, and the only question is how cheaply you can get that extra energy.

            My own goal is to come up with a design that will be cost effective even for very poor people, and even if they have to do the tracking manually – which is actually quite workable, since the work involved only amounts to about one minute an hour, and requires no special strength.

            I’m sorry I do not have a better answer in terms of concrete design details. It is one of those things that is very hard to describe in words, and very obvious once you see a picture. I just don’t have any pictures yet.

            It is ground mounted, however, for many reasons, not least being safety.

  6. johnnewton 5 years ago

    A strange story. I was visited by a rep from the reputable company who installed our rooftop panels. His job was to persuade me to buy five more before the Libs took away the advantage. during the discussion we began to talk of climate change. totally natural he said. The sun is getting larger, that’s what’s causing it. Intrigued, when he left (without making a sale) I looked it up. Yep, he’s right. It’ll take 5 billion years. What a strange choice to sell solar panels.

    • Giles 5 years ago

      So, does a bigger sun mean higher output from the solar modules?

      • Giles 5 years ago

        If so, then maybe you need fewer modules. I think his sales pitch needs refining.

      • Chris Fraser 5 years ago

        It depends how much of the solar harvest is contained in the infrared end of the spectrum, probably very little 😉

    • wideEyedPupil 5 years ago

      So rate of efficiency improvements in solar PV panels is outstripping growth in sun by a billion or so percent per year!

      You could have reminded him Earth is currently moving away from the sun due to Milankovitch cycles!

  7. John Silvester 5 years ago

    It’s not surprising that the two main political parties fall in line with the major industry groups. Cheap, abundant fossil fuels has long been seen a national competitive advantage, with comments like “Saudi Arabia of coal” being not too uncommon. Both parties have a long history of policy development to promote fossil fuel interests for the “greater good of the country”.

    Ministers receive advice from their government departments that have long ago been captured by the fossil fuel industry groups. For an insiders view of how this has come about, read Quarterly Essay – Quarry Vision by Guy Pearce from a couple of years ago.
    Even with the introduction of the carbon price the Labour Government went to great lengths to reassure everyone that the coal industry is safe and would continue to grow while introducing policies aimed at reducing our dependence on coal. This policy disconnect is obviously not shared by the Abbott Government, as evident by the rush to overturn any and all legislation that would reduce our reliance on fossil fuels.

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