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  1. #556
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    Quote Originally Posted by AlexS View Post
    Does anyone know if there is much research being done into tide & wave generation. It seems to me that this could be suitable for peak & base load generation, and wave generation would be close to where most people live, on the coast.
    Or on a remote island.

    Full steam ahead for King Island wave power trial - Australian Renewable Energy Agency
    Stay sharp and stay safe!

    Neil



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  3. #557
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    [QUOTE=Toymaker Len;2173978][QUOTE=Beardy;2173838]Really? You are checking to see if I have logged on as you are busting to win an argument

    "I am not particularly a fan of the whole CC mantra / religion"
    Well if you accept the science and understand what science is, then you should understand why people (children included) are getting pretty upset. The planet is plunging into runaway climate chaos and the biosphere is taking a hit so big that it qualifies as an extinction event on par with an asteroid strike or having a super vulcano blow up. It is not a theory, it is actually happening. Meanwhile our political system has been pretty much bought up by the vested interests of the fossil fuel lobby supported by a massive media disinformation campaign.(see what the Koch brothers have done...“Kochland” Examines the Koch Brothers’ Early, Crucial Role in Climate-Change Denial | The New Yorker) Not one single politician from either Labor or Liberal will stand up and lead a transition to a zero carbon economy despite the rest of the world heading in that direction as fast as it can.
    Who wouldn't be upset?

  4. #558
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    And if you can't understand that there has been a huge propaganda effort to protect fossil fuels have a look at this...New IMF study says the 'true cost' of fossil fuels is actually about $5 trillion.
    The basket of money they are protecting looks to be over $5trillion. And think of the poor old Saudis, what would they do for folding money if the world transitioned to what is essentially free energy.

  5. #559
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    Default Micro generation

    Raising here a different perspective: Micro generation.

    Most of our discussion so far has been on the big picture; where will the base load come from to power Australia through the evenings when the sun goes down and the wind has dropped.

    From what I can see, big industry has accepted the science on CC and its impact on the economic environment in which they will operate and is ready to take on that challenge. They are the big users of power so will no doubt find solutions.

    Enough renewables to meet SA’s needs five times over: Sanjeev Gupta’s plan | Repower Australia

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    Leaving that challenge aside for big industry, I would like to give a little focus to micro generation.

    In 1918 my grand uncle returned from the war in Europe with a small hydro generator in his luggage. He installed it in the creek on his dairy farm and he was one of the first in the district to have domestic electricity. It ran the milking machines in the dairy and the lights in the dairy and house (32v DC) and it worked for decades before a flood washed it all away. It paid for itself many times over in that time.

    At about the same time, on a different family property, an hydraulic ram pump was installed at the bottom of a waterfall and that pumped water many hundreds of feet up the hill to the house for countless decades. It never cost a cent to run. It didn't generate electricity but could have done so if a return pipe with generator was installed back at the bottom of the hill.

    I have some friends who live in a remote area on Kangaroo Island (not the bushfire end) and they chose to go with their off-grid setup because the cost of running the connection to the grid was going to be prohibitive. Many decades on they are still self sufficient (and comfortable so) with solar and old style battery storage. They have a backup generator but it has rarely been used. They are well ahead on cost and their carbon footprint is very low.

    Rooftop solar across Australia is in essence micro generation. As I write (1:45pm) it represents 20% of the total generation. Adding small domestic battery storage to that (micro storage) when it becomes economical to do so will offset some of the demand for base load for domestic use.

    What we seem to be missing with micro generation is other sources than rooftop solar. With many people owning their own bit of rooftop real estate it is understandable that is where it has happened so far. The missing sources seem to be micro wind and micro hydro generation.

    Discussion some time ago with a company that specialised in small scale wind generation (mainly for off grid use) made me aware that one of the issues is the reluctance by grid operators to connect such a variable source of generation to the grid. Unlike solar that has a relatively smooth output, small scale wind in domestic settings is highly variable. Paul has raised the challenges from instability in the grid. The grid managers just don't want to know about any generation source that is going to add any further instability.

    Anyone who has added a large domestic rooftop solar lately will know that retailers are also adding smart meters at the time as well as real time communication back to their control centres to monitor solar exports. I presume that is to do with the retailers optimising the sale of their excess into the spot market.

    If pumped hydro is an economic proposition at a macro level, it seems to me that pumped hydro at a domestic micro level may also work. Around our way everyone is required to have a water tank for fire fighting purposes that is never grts used for anything else and is never required for most of the year. We are also quite hilly here (Adelaide Hills) so most properties have a drop from one end to the other. Adjoining properties can when combined have a significant elevation drop. I'm sure that various systems could be put together that pumped water up to a holding tank with whatever power source made sense, eg traditional wind mill, wind turbine or ram pump, or even solar if that works out on the sums. With a smart meter and comms connected, the retailer could then switch on your hydro generator to deliver a steady kW feed into the grid for a period of time, presumable at peak use periods. Then your system would prime itself for the next time.

    Once proven as an off the shelf and workable system, local councils, schools and community groups could adopt it where suitable in the same way that they have adopted rooftop solar.

    As rooftop solar has proven, micro generation can make a difference.

    Any further brain waves on micro generation out there?
    Stay sharp and stay safe!

    Neil



  6. #560
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    NeilS, you are exactly right: Evergen Energy System and a pricing model: Evergen Battery Only Price Guide ACT

    One generates local power via Solar, wind and hydro. The batteries store it. One uses their own storage first, then the grid, or alternatively (or in parallel) feed it back in when price is high.

    It charges the battery when price it low. It uses a smart pricing/charging/release system that talks back to Evergen constantly.

    An example of hyper-local hydro: The gravitational vortex water turbine puts small hydro on the map - EE Publishers

    It works. Its a thing. Its real and it pays handsome dividends.

    IF EVERY NEW HOUSE HAD ONE..... and 10 or 15 solar panels.... well, it changes things.

  7. #561
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    Thanks Neil. I was aware of an earlier tidal energy trial that was damaged and abandoned in a storm quite a few years ago, and for Australia, as others have said, the highest tidal ranges are well away from population centres. Then again, many coal mines are well away from population centres too. Collinsville isn't that close to Brisbane. Wasn't aware of the Port Kembla one.
    Tidal generation also has to find a balance between land value and closeness to demand centres, but then again, so does any other form of generation.
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  8. #562
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    Quote Originally Posted by NeilS View Post
    Looking at the AEMO/NEM maps I keep seeing how critical the interconnector network is to the eastern states. The glaring gap is a connector between WA and SA.




    A link between say Woodina in SA and Kalgoolie in WA is about 1,500km. The Bass Strait interconnector is only abt 200km, as the fish swims, so a SA-WA interconnector would be a much more significant undertaking.


    A recent report looking at the proposed additional interconnectors between SA-Vic, SA-NSW and SA-Qld put the cost (as of 2018) at between $0.75m and 1.00m/km. So an above ground interconnector between SA-WA could cost about $1.5bn, not all that more than some of additional interconnector options currently being considered by SA.
    I'll buy into this

    If you want to integrate the WA and Eastern state grids, you would need a minimum of TWO interconnectors both operating at 330 or 500 kV.
    (you would want at least two links to provide a level of redundancy sufficient to allow the WA coal plants to shut down)
    The distance from Portland to Perth is about 3300 km, and transmission the line losses (AC) would be about 10%, perhaps as high as 20% on a hot day.
    At $1M/km, a pair of interconnectors would cost about $7 Billion. And at the distances involved, over 3000km, high voltage DC is looking like the way to go.

    To totally replace coal and gas fired generation in the Perth to Kalgoorlie region, would likely require a minimum of FOUR high voltage interconnectors, each capable of supplying 1000 Amps -- say $14B as a starting figure. (you have to allow for cloudy days with little to no wind.)

    So, IMO it's doable -- but the economics would require a substantial Government investment.
    regards from Alberta, Canada

    ian

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    Quote Originally Posted by woodPixel View Post
    This whole base load thing is such coal-agenda crap. Its a lack of imagination, vision, technology and drive.
    nope

    the whole base load thing is about synchronization. Your 50Hz solar or wind generator must be in sync with everyone else's otherwise you end up with a blackout on the scale experienced in South Australia.
    regards from Alberta, Canada

    ian

  10. #564
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    Quote Originally Posted by Bushmiller View Post
    The benefits of electric cars are diminished if fossil fired power is used to recharge them.

    Regards
    Paul
    Thats spot on Paul, and something that many people don’t realise.
    I was putting some papers together on noise pollution and came across these interesting figures for Fuel Life Cycle CO2 in g/km

    Petrol car - Toyota Corolla

    B856FE14-6614-4374-8F27-011F91203A83.jpg

    Electric car - Tesla

    277C1325-25F0-4510-963A-E0377D3E3CC4.jpg

  11. #565
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    Quote Originally Posted by Lappa View Post
    Thats spot on Paul, and something that many people don’t realise.
    I was putting some papers together on noise pollution and came across these interesting figures for Fuel Life Cycle CO2 in g/km

    Petrol car - Toyota Corolla

    B856FE14-6614-4374-8F27-011F91203A83.jpg

    Electric car - Tesla

    277C1325-25F0-4510-963A-E0377D3E3CC4.jpg

    Agreed that recharging EVs from locally produced Solar power is the optimum way to go, but isn't it a bit misleading to compare figures for a sedate car such as the Corolla which does 0-100 in around 8-9 seconds (petrol), with figures for a performance vehicle (EV only) which does 0-100 in "as little as 3.4 seconds"?

    If it were two petrol vehicles with those same 0-100 figures, wouldn't you expect an even bigger difference in the gm/km CO2?
    Regards, FenceFurniture

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  12. #566
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    Quote Originally Posted by ian View Post
    nope

    the whole base load thing is about synchronization. Your 50Hz solar or wind generator must be in sync with everyone else's otherwise you end up with a blackout on the scale experienced in South Australia.
    Ian

    Yes, the "base load" phrase incorporates a number of concepts and can loosely be termed to be the section of the market that is always generating. It is those machines that are both reliable and cost effective. The grid, or the market if you prefer, acts as one ginormous unit and is physically locked in to generating, in this country, at 50Hz which means that our generators rotate at 3000rpm. When a machine is synchronised to the grid it cannot travel at any other speed. (In the US their machines are at 60Hz which means their generators rotate at 3600rpm and this is the problem if we wish to buy any of their power tools as the frequencies are incompatible).

    If you have your own portable generator or are otherwise off the grid you will be generating close to that speed (3000rpm) but there will be a greater range, which generally your motors and appliances will tolerate. In the large system, the grid, it cannot tolerate wide swings and needs to regulate that aspect.

    I have made quite an issue of the way the competitive market dictates the price, primarily on demand, but it is not the only aspect of pricing and at this point I should draw your attention to the grey box on the top left of the pic below:

    NEM Load and price. 1828hrs 13 Feb 2020.PNG

    Those sections relate to how the grid is regulated and stability maintained. The "L" prefix is for lower and the "R" preficix for raise. Now this bit is important: Solar for the moment cannot do this. Hydro can and the storage batteries, as I have already stated, are superb at it.

    If you go to the link below (I did note this back in post #496 ) and scroll down the page you can see the descriptors. They are for raise and lower over 6 seconds, 60 seconds and 5 minutes.

    AEMO | NEM data dashboard

    Nothing is easy.

    Ian in your other post linking the billionaire, the figures seem a little vague. One statistic that to my mind is deliberately mis-represented is the power figure. There is a big difference to how much is produced per hour (this is the figure we refer to in the industry) and how much is used over the course of a year. I am not quite sure how a 280MW solar farm converts to 10GWs even over the course of a year, particularly when you factor in that it can only produce a quarter (optimistic assessment) of that 280MW/hr over the entire day. As to it producing five times as much as the requirement for SA???

    Regards
    Paul
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  13. #567
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    Quote Originally Posted by Bushmiller View Post
    The grid, or the market if you prefer, acts as one ginormous unit and is physically locked in to generating, in this country, at 50Hz which means that our generators rotate at 3000rpm.
    Are you sure? Google tells me the generators at Tumut 3 rotate at 187.5RPM. 3000/187.5=16, so I assume they are 16 pole generators?

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    Quote Originally Posted by jack620 View Post
    Are you sure? Google tells me the generators at Tumut 3 rotate at 187.5RPM. 3000/187.5=16, so I assume they are 16 pole generators?
    Jack

    That is quite correct. There is always an exception that proves the rule.

    The hydro machines are a very different set up. They are much larger diameter, mounted vertically and much bigger diameter than the steam generators. Centrifugal forces play a big part. Check out the speeds of circular saws of different diameters to gain an appreciation of this.

    The 60Hz generators tend to be longer and slimmer than our 50Hz machines of a similar capacity. You see a similar comparrison with three phase motors. The two pole motors rotate at a nominal 3000rpm (more like 2950rpm) and a four pole motor is a nominal 1500rpm (1425rpm in reality).

    Thanks for pointing this out.

    Regards
    Paul
    Bushmiller;

    "Power tends to corrupt. Absolute power corrupts, absolutely!"

  15. #569
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    As the subjects of hydro and DC links have been mentioned it is interesting to look at the Itaipu Dam hydro station which produces more power than any other power station in the world, despite not having the greatest capacity (the difference between rated capacity and actual ability). Half the twenty 700MW units supply power to Brazil at 60Hz but the other ten units, which supply power to Paraguay generate at 50Hz. However, those 50Hz generators easily supply Paraguay's needs and the surplus is sent to Brazil.

    "Of the twenty generator units currently installed, ten generate at 50 Hz for Paraguay and ten generate at 60 Hz for Brazil. Since the output capacity of the Paraguayan generators far exceeds the load in Paraguay, most of their production is exported directly to the Brazilian side, from where two 600 kV HVDC lines, each approximately 800 kilometres (500 mi) long, carry the majority of the energy to the São Paulo/Rio de Janeiro region where the terminal equipment converts the power to 60 Hz." (from Wikipedia)

    I was talking to a colleague at work and he pointed out the DC transmission lines are more efficient, but of course they have to have inverters to transform the power to and from AC.

    Just out of interest and I think those of you who are advocating some of the newer technologies may be particularly interested, this is a list of the largest power stations in the world. Some big stations for tidal/wave/geothermal that I was not aware of at all: Just goes to show! Just remember my chorus of "it has to be economically competitive." What is economic in one country is not necessarily so in another.

    List of largest power stations - Wikipedia

    I did see a reference to a proposed tidal facility, which if it went ahead would be the largest station in the world of any type, but now I have lost where it was.

    Regards
    Paul
    Bushmiller;

    "Power tends to corrupt. Absolute power corrupts, absolutely!"

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    Quote Originally Posted by Bushmiller View Post
    Jack

    That is quite correct. There is always an exception that proves the rule.
    Paul, don't you hate it when you simplify the explanation to suit the non-expert audience and they call you out on it. Can't win sometimes.
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