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46 responses to “Climate clippings 88”

  1. Graham Bell

    Thanks Brian and JohnD.
    The article on new directions in battery technology cheered me up no end …. and, of course, it fits in well with my own reference for lowering the need for electricity rather than finding ways to produce more.

    Looming gas supply shortfall? Perhaps this is as good a time as any to change our national anthem from “Advance Australia Fair” to “Stupid Greed Everywhere”. One of these days it will sink in that some exports are very, very expensive.

  2. Terry2

    An interesting aside: the global insurance and reinsurance markets are already gearing up to more frequent and more intense storms – hurricanes, typhoons and cyclones – in the regions between the tropics of cancer and capricorn. Their response is essentially to either pull out of some areas altogether or place premium loadings on insurance policies in those regions.

    At least they are convinced of the science of climate warming and the immediate impact in economic terms.

  3. Len

    I find Item 1 above interesting. A couple of months ago I obtained a quote for a ‘stand alone’ electricity system for our son who has an acreage block of land west of Ipswich. The block has fantastic views, but is ca. 1 km from the grid power line … hence, a few poles and great cost to make the grid connection. A system to provide reliable power in all weather conditions (solar panels with storage batteries and automatically switched diesel generation back-up) was just under $50,000.

    This is probably cheaper than grid connection and a lot cheaper to run. But the interesting part is that the battery pack quoted for the system was half the cost and weighed 1.6 t, needing a decent storage shed on its own! So ….. all efforts to make batteries cheaper as well as less bulky will be a step in the right direction!

  4. David Irving (no relation)

    Len, your son might want to shop around. I’ve just had a quote for a 10kWhr / day system (solar panels, wind turbine, batteries, backup generator and all associated electronics) of just short of $18k, including installation. I will need a shed, but only a small, cheap one.

  5. philip travers

    DIY Syn-Gas smoke does not get in your eyes!

  6. Bernard J.


    David Irving (NR) is right. My area is ‘remote’ and there are many folk with renewable systems, and I don’t know anyone who has paid more than $20k. Many have paid much less, as they don’t have a high need for power.

    It pays to hunt around.

  7. Len

    David @4 and Bernard @6

    Many thanks for your helpful comments. Someone I met at the recent Get-up Climate Action meeting in Brisbane also mentioned the desirability of adding a wind turbine into the mix (wind often still blows after dark in the early evening when power is typically needed and solar panels are idle). Also, maybe the spec for the system I was quoted had far too much reliance on battery storage of power, with a cost of $24,000 in this component alone!

  8. John D

    Brian: In item 6 you said:

    I keep being told that although demand has reduced in SEQ the reduction has come off the shoulder period. During the peak period in the late afternoon/early evening demand continues to increase, although overall it’s down.

    However, we need to distinguish between when the peak occurs on an average day and when it occurs on peak demand days.
    It is a shame I can’t copy graphs into comments. However, if you look at fig 1 here, you can see that the Qld peak on an average day occurs at about 6 PM. (Have a look at fig 2 while you are there. It shows how much damage rooftop solar is doing to the fossil power company’s business model, particularly those that make a large part of their profits selling expensive peak power.
    On the other hand, if you look at the graph of NSW peak demandshere the peak on an average day occurs, like Qld at about 6 PM. On the other hand, the peak for the three hottest days occurred at about 3 PM, well inside the summer PV production period.
    In addition, the peak for the 3 hottest days was a massive 50% higher than the average peak. It is these unusually hot days that are setting grid and generating capacity requirements.
    (Having said this, the winter peaks are high in the southern states. Solar is not going to make much difference here.

  9. John D

    I am interested in more details from those who have off grid systems. A few questions:
    What is the average daily power consumption?
    What is the power demand for high demand days?
    What is the average daily output of the renewable system? How much does this change over the year?
    What is the capacity of the back-up diesel generator?
    What percentage of power comes from the diesel generator?
    What is the energy storage capacity?
    To what extent can you cut back on power demand without having to shut down things you think are important?
    Have you got some smart way of taking advantage of the free power that comes when the batteries are fully charged and you are producing more renewable power than you need?

  10. John D

    Brian: I have been saying for a long time that we need contracts for the supply of backup dirty power capacity as well as renewable power capacity. Contracts for backup are needed as part of a strategy for ensuring that the transition to clean power can take place without blackouts.
    The German virtual baseload system sounds like much the same thing.

  11. Salient Green

    Batteries are much more expensive than generators. A small battery bank is essential for instant response and meeting peak loads but lifetime costs of relying heavily on batteries can be up to five times that of relying mainly on backup generator.

    The first consideration is always to have the home as energy efficient as possible.

  12. Bernard J.

    Thanks for posting those links here Brian.

    I was originally going to post here but I wasn’t sure if the thread was intended to discuss your points in the OP, so I continued from the previous discussion. It’s good to know that I could have used this thread.

  13. John D

    Brian: @11 I don’t have the graphs for SEQ. Would expect them to be similar because the very hot day peaks are driven by air conditioners. Keep in mind that air conditioner power is proportional to temperature difference squared. If you are trying to keep your house at 23 deg C it takes 4 times as much power on a 43 deg day compared to a 33 deg day.
    I agree that the public is not going to be very tolerant of blackouts. We didn’t have blackouts last summer because rooftop solar provided the power during very hot day peaks.
    @12 We can reduce the risk of blackouts by putting more equipment on various types of off peak (on command) power. For example, a form of off peak with only short times off peak and a guaranteed time on over a relatively short time might be suitable for fridges and air conditioner compressors. Putting all air conditioner compressors on command power would mean that there would be no total blackouts on hot days.
    I think time of day charging is a myth promoted by companies that will share the installation cost bonanza. The power bill for the average Qld home is about $6/day. How many people are going to hover over their meter to save a few cents/day? And on very hot days? If the temperature is in the forties people will pay a lot to keep their air conditioner going. Any drop in peak demand will be due to pensioners dying of heat exhaustion while the rich continue to be comfortable.
    @13: My concept of dirty standby contracts is that provide the certainty for power companies to do the maintenance required to keep standby units ready to do the job. Without this the risk is that the wrong dirty power will shut down just because the companies have gone bankrupt or have decided to simply run the power plants down. (You could end up with all the power stations shutting down in Qld or baseload power plants keeping going whereas what you need during transition is fast response peaking power.
    We could avoid the need for dirty power contracts by prioritizing solar thermal with storage and back-up. However, if we are spending a fixed amount per year on renewable installation we may end up using our carbon budget more slowly by installing the cheap renewables first and using dirty power for back-up.

  14. Val

    I’ve just had solar panels installed on the roof of the apartment block I live in. It’s been quite a saga – I won’t go into the details here as I’ve posted about it on my blog http://bit.ly/18aD2xa

    I’m very happy so far, in spite of weather in Melbourne turning to winter yesterday, with rain, hail and thunder today!

    My flat is ground floor, double brick, next to a park and has external sun blinds (which I use! Some poor benighted people don’t, even though they are extremely effective).

    The flat rarely (maybe two or three times a summer) gets above 25C inside in summer so I haven’t felt the need for aircon, but I’m interested in one question:

    John D @ 17 – or anyone else who can work it out – absent command power, would it be better for people who have solar and aircon, and are out of the house all day, to set their thermostat really low on really hot days when there’s a lot of solar power? Then when they come home, they can turn the thermostat up (or possibly even turn it off) as the shade comes over. That could reduce their costs and the peak, couldn’t it?

  15. David Irving (no relation)

    Brian, you’re correct that my Doomstead is in SA, and in a fairly windy valley. The battery bank on the system proposed for me is quite small (12 x 2V batteries), but still expensive. (I don’t have the quote to hand, but from memory it’s close to 1/3 of the cost of the system.) I anticipate all I’ll be running from it is fridge, freezer, stereo / TV and lights (at night) – I’m not interested in an air conditioner.

  16. Tim Macknay

    Brian – just a quibble, but your heading for Item #4 should read “2c per kWh (i.e. kilowatt-hour), not 2c per kW. At 2c per kW, the price of solar would have to come down by a factor of around 100,000 or so. it’s currently around $2 or so per installed watt.

  17. John D

    Val: If you can’t sell surplus power cooling the house down during the day makes sense even if you are out. It will reduce the amount of power you will have to buy to cool the house , cook etc. when you come home.
    It would make evenmore sense if your unit is well insulated and you deliberately increase the unit’s thermal inertia.

  18. Val

    John D @22
    Yeah the point I was getting at was not just about the individual costs but also about peak use – in southern states at least, peak usage has been caused in recent years by people coming home on very hot days and turning their air conditioners on.

    If enough people had solar and left their AC on during the day, it could reduce that peak, especially if they turned the thermostat up when they got home (or even turned the AC off then).

    Setting the thermostat low (20 or less) would be effective as then you could turn the thermostat up to 23 or so when you got home and the AC wouldn’t actually have to do much. However thermal comfort comes into it then as you don’t want to walk into a house that feels cold ( although some people I’ve heard of keep their houses at that level – 20 or so – in summer, which I’d say was unnecessary but that’s another issue).

    Turning the AC off is a different proposition I guess particularly because, even though the shade comes over about six or so, the sun doesn’t go down till after eight in summer in southern states with daylight saving, and minimum temp on hot days often isn’t reached till early hours of the morning. I remember we had some days last year when the temp was still up around 30 at midnight. So in that case the house could potentially heat up again at night if the AC was off, even without direct sunlight.

    As I said it’s not a personal question for me as I don’t have an AC, but heating and cooling practices – and how they can be changed – are significant in my research. The ideal is to encourage a shift to practices that promote health, reduce energy costs to individuals and households, and reduce emissions, all at once. For low income groups, this also requires government or community investment in infrastructure.

  19. John D

    Val: A few comments on your AC issue:
    You will minimize your power consumption by only running it when you need it. If you run it all day on a hot day you increase the heat flowing into the house. It takes power to pump this back out again.
    You can use timers or remotes to allow you to turn the air conditioner on in time to cool the house before you arrive home.
    You can also reduce air conditioner power by using a a higher temp setting and using fans to get comfortable. A typical fan will draw about 50W running at the high setting.
    Peaks are a bit more complicated. The peak that determines the investment required in the power distribution system is either the winter peak for the few most miserable days or the summer peak on the few hottest days. In NSW the winter peaks are almost as high as the summer peaks but I am not sure when they occur. In Vic the winter peaks will be much lower because of all the gas heating.
    In NSW the summer peak occurs around 3 PM so turning your air conditioner when you get home at 6 PM doesn’t affect the investment required in the power system.
    The NSW advice is based on 2011 figures More recent investment in rooftop solar may have pushed the time that determines grid and non-solar investment requirement back in the day. (The dramatic change in solar PV seems to have both reduced the daytime peaks on hot days as well as removing the need for grid upgrades. See here the effect of solar PV on the revenue variation vs time of day for Qld

  20. Moz of Yarramulla

    Len, DInR, demand reduction all the way. You will almost certainly find that buying new fridge and freezer drops the cost of your system far more than the cost of the new appliances. The SunFrost fridges and freezers from the US are a perennial favourite with ATA members despite not meeting the Australian standard (“must be able to cool an SUV-load of groceries from 40° to 4° in an hour”) because the compressor is a tiny wee thing that’s designed to work *with* the superinsulated box rather than against it. Even if you just switched to a couple of chest freezers (convert one to a fridge) you’d come out ahead. The standards for freezers are very different to fridges, and out DIY conversion used ~1/3 the electricity of the fridge it replaced. Well, for a while, we got it out of hard rubbish and it died after a year.

  21. David Irving (no relation)

    I’ve been using a chest freezer as a fridge for about 18 months, Moz, but it’s just too bloody inconvenient. I’ve caved, and bought the most efficient normal fridge I could find (~ 0.7kWh/day).

  22. Tim Macknay

    DI(NR), what type of fridge is it? I’ll be looking for a new one shortly and I plan on getting the most efficient one I can find.

  23. David Irving (no relation)

    An Electrolux, Tim. Model is ERM4307SD (fridge only). RRP is about $2600, but you can do better by asking around.

  24. Val

    John D @ 24
    Ah thanks very much John much appreciated. I’ve skimmed through the post you linked to briefly but I’ll go back and look more closely.

    Some of the projects I’ve been looking at in my research have brought together people with technical expertise with people working in community development/health promotion in constructive partnerships – useful direction.

    And of course what you’ve said also reinforces the importance of housing construction, insulation etc and good use if shading and ventilation. There are also some simple things, like people not being able to leave windows open at night for security reasons, where small things could make a big difference

  25. Tim Macknay

    Thanks. Will look into it.

  26. Len

    Val @ 18, I know John D has given you plenty of feedback on your question, but I thought it might be useful for you if I outlined the approach we have taken in our household. We have installed solar panels on our north-facing roof (in Brisbane), and have a multi-head reverse cycle AC system throughout the house (only 4 heads, through a bit of trickery here and there, but it all works fine – you can’t be in every part of the house simultaneously!). Even in the middle of a Brisbane heatwave, we never leave the AC on when we are out of the house to cool it down for when we return (or even set a timer in advance). Why? We find that it only takes a matter of a few minutes for the house to be pleasantly cool (cf outside temp) when we turn the AC on upon our return. And even though we have a pretty-well insulated house, the AC would have to work hard to keep the house cool when we are not there, wasting a large amount of power that would be better-off going to folks who are at home at the time.
    In winter, it’s really the same as above as well. Within minutes of our return to the house, the very efficient reverse cycle process in our AC system has taken the chill off the air. The “magic” of the reverse cycle process is doing its work by concentrating the heat in the cold air outside and pumping it into our home at a delightfully warm temperature! Much more efficient than direct heating with electricity.

    And a final comment. In our enthusiasm for solar panels back when the feed-in tariff was more favourable in Qld during the initial stimulatory phase of the adoption of solar panels, we filled the entire north-facing slope of the roof on our house with solar panels. So what to do about hot water when our electric system came to the end of its life? After much investigation, we installed a ‘heat pump’ HWS. It has a smart panel on it that allows us to choose what times of the day it extracts heat from the atmosphere and heats our water (it’s possible to specify up to 3 time slots each day). So we can set it to heat water in the storage tank late in the evening when the peak load on the grid power system is well past. And the other advantage, of course, is that more of the PV panel power that we generate is being fed back into the grid, generating income to pay for the whole system …… about 4 yr pay-back period, same as you mentioned.

  27. Len

    Moz @ 25 and others. You (ie, I) learn something new every day! I had never heard about the freezer trick. And in our household, it’s been me who has been canvassing the case for a new, more efficient fridge (lay-out as well as energy efficiency). Now I will have extra bargaining power! Cheers!

  28. Len

    BTW, I can’t understand why some entrepreneurial company has not yet devised a heat pump HWS (see 21 above) that directs the cool air produced as part of the process into the interior of the associated dwelling when the interior temperature is uncomfortably high. Surely this would not take much in the way of sensors and electronic switches to achieve? This would reduce (or maybe eliminate) the need for a separate AC system.

  29. Val

    So I have had a big calculation session around my electricity costs after installing solar and three key points seem to emerge:

    - it will take me a lot longer than I thought to recover the cost of the system, because my usage costs are low – specifically I pay more for provision of service than for usage, and the FIT is only 8c per kWh so even though I will produce more power than I need for most of the year, it doesn’t look like it will be enough to cover the service charges;

    - my energy provider is apparently paying me 8c per kWh for solar, and selling it to others as green power for about 25c per kWh;

    - my energy provider (Origin) has just written to me saying it is putting usage costs down by approx 1.5c per kWh and service charges up by about 7c per day. (Apparently this will lead to about $50 yearly increase in average bills.)

    I know there are a lot of people on this thread who know a lot more about this stuff than I do, but surely this is all just an outrageous case of protecting profit? I don’t understand the politics of this – I mean how do they get away with it?

  30. Salient Green

    Val, yes it is just protecting profits but I thought they had to go through an Energy Regulator before raising prices. The site below often has stories along these lines if you don’t know about it already.
    Just try to use as much power as possible while your panels are producing and as little as possible while they are not. I have to do the reverse as I get a $0.54/kwh FIT until 2025.

  31. Val

    SG @ 35
    I think they do, but how much can we trust that process? I mean how can they pay 8c and charge 25c? Isn’t that profit gauging?

    Apparently over a million households in Australia now have solar panels, http://reneweconomy.com.au/2013/solar-milestone-1000000-pv-systems-installed-in-australia-44201 so hopefully this will all become much more political soon.

  32. John D

    Val: You might be interested in this article on the effect of rooftop solar on Qld household power bills.
    It was concluded that, for Qld:

    Rooftop solar at 44¢kWh actually reduces the typical power bill by $65/year. It was estimated that the feed-in tariff would have to go above 97¢kWh before rooftop solar increased the typical household power bill.

    I have also had a look at how the Qld Competition Authority (QCA) came up with the 8cents/kWh price. the conclusion here was:

    The whole emphasis of the QCA approach was on being fair and reasonable to the retailer, not the producer of the exported solar PV (In effect, this approach is the equivalent of pricing payments to dairy farmers so that Coles could maintain its profit margin while it persists on selling milk at one dollar/litre) Protecting the profits of the monopoly power distributors was also considered important.
    The QCA approach was justified on the basis of the first national COAG principle that: “The payment for PV exports should be at least equal to the value of that energy in the relevant electricity market and the relevant electricity network it feeds into, taking into account the time of day during which the energy is exported.” In the QCA approach the “at least” was ignored and replaced with “equal to”
    NOTE: The COAG principle was developed at a time when no-one would have thought it possible that the fair and reasonable price to the retailer may end up being well above the minimum fair and reasonable price to the PV producer. The QCA avoids this problem by finding excuses to ignore all the major benefits that solar PV actually gives to the retailer – But it could come unstuck if these excuses are successfully challenged. These potential problems could be avoided by setting out to find “a fair and reasonable price to the PV producer” based on the PV producers costs.

    In terms of the relevant market the QCA said:
    “It is important to draw a distinction between the value of exported PV energy in the retail
    electricity market and its equivalent value in the wholesale spot market. The Authority
    considers that the relevant market in this case is the retail electricity market, not the
    wholesale electricity market.
    The QCA went on to say “Small residential PV exporters are not direct participants in the wholesale market and their exported energy only has realisable financial value in the
    presence of the retailer as an intermediary. Without the retailer acting as an intermediary,
    there is no market or mechanism for small PV customers to on-sell excess PV electricity, nor
    any means of accurately valuing it. Therefore, the relevant market should be the retail
    market. On this basis, it follows that the starting point for valuing PV exports should be the
    value that the retailer ascribes to any exported PV energy that it can on-sell to its customers.”

    In cased you missed it, being fair to consumers didn’t get a mention.

  33. Val

    Well John I think we should be jumping up and down and having a bit of a revolution about this.

  34. BilB


    There will be a power revolution eventually, and it will be all about distributed generation. The big lie in the valuation of your local solar is that when it is fed into the grid, it is not feeding a consumer in another state, in which case the “wheeling” cost (wheeling is the term used for transmitting electricity over the grid) would be about 30% of the retail price, but to a neighbour just down the street who is running a washing machine, or a bit further away to a local super market to run their fridges or air conditioning. The cost of this local transmission is far less than the 30% required for long distance high voltage transmission. And the transmission losses are far lower over the short distance.

    So where the observation that “greed breeds competition” holds true, the power retailer’s position of maximising their profit at the expense of the consumer and the distributed power producer, s new breed of energy brokers capable of making local energy deals will spring up.

  35. Moz of Yarramulla

    I wonder how cheap PV has to get before it’s worth shoving it on the roof without a feed-in tarrif at all? I’m not even talking about using car batteries, just about using it to run (eg) a heat pump to overdrive the house during the day, scheduling washing machines and dishwashers to run during the day, and so on. It’s already at the point for my boss, since us lackeys run the aircon all day, every day and he has been running the numbers and whining. Mostly about the inconvenience of getting it installed, actually.

  36. Emma

    Hello Val, while reading the comments on this page I saw that you are only getting 8c/kWh from Origin (which is a really anti-RET company by the way). Why not look at alternative power companies like Diamond Energy or Sanctuary, that voluntarily pay a higher FiT. We are with Diamond and they pay 20 or 25c per kWh, depending on the brand of panels installed. I think they both operate in Victoria.

    Love it that you got panels installed for your unit – sounds like a great case study for sharing with groups like 100% Renewables.

  37. Val

    Emma @ 41
    Hi Emma, thanks for that. Your comment reminded me that I did hear about Diamond with one of the companies when I was getting quotes, the company had a deal with Diamond which sounded really good.

    I’d forgotten about it because I eventually decided to go with Braemac, who are the preferred provider for Positive Charge (http://www.positivecharge.com.au) and I thought that might be a better option for someone like me who is not particularly good on the technical side (not hopeless, but not necessarily strong on it).

    I wonder if I can now switch to Diamond – I will look into it. Don’t know if it will be possible now, but will see. I’d heard Origin were being sh-ts about the RET, advocating for it to be reduced – disgusting.

    Btw I’ve changed the name of my post on my blog (it was a bit misleading) so will send the new link again for anyone interested. Great to hear from you.

  38. Val

    Here’s the new corrected link for my post on getting solar panels on an apartment roof http://bit.ly/IyEoXc

    I remembered another reason why I thought it was good to go through Positive Charge and Braemac as their preferred provider – Positive Charge are supported by five local Councils, including Moreland Council where I live. I thought that from the point of view of the Owners’ Corporation, that was probably also helpful in seeing this as a reasonable proposal.

  39. Emma

    Thanks for the revised link Val. Sounds sensible to go with Braemac in your case. Good luck with Diamond. I have heard some grumbles that they and the installer recoup the cost of the higher fit by inflating the install costs, but the provider I went with was cheaper than others for the same hardware so I doubt it. Whatever you do, consider switching away from Origin. Even AGL is better.

  40. John D

    Bilb @39 I have been told that my electorate (Ryan, Qld) is a net exporter of power at some times of the day so I assume that some of this power would actually go through transformers before reaching a customer. Even so, if you look at what I said @37, the calculation for a fair price for FIT in Qld was based on the same grid charge for power going from Gladstone to B’bane was the same as my excess power going to the house next door which still hasn’t got solar PV.

  41. Fran Barlow

    I found this interesting: