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Post by David Walters on Jun 20, 2012 3:19:24 GMT 9.5
This was post on the Green Left list. Comments?
Oh don't get me wrong, David. I'm all for rural electrification. If my farm was
connected to the grid I would be able to sell my surplus energy from my solar
installation, instead of having my solar panels simply switch off at 1pm in
summer once my batteries are fully charged. My neighbours look at my free
electricity and independence from power blackouts, and consider whether their
savings would earn them more as solar panels on their structures earning tariffs
feeding into their grid connections rather than sitting in the bank as dead
money waiting to be lost in the next banking crisis.
Quite frankly David, you speak without experience and make assertions based on
misinformation (although I am amused that you have experience in viable
geothermal power generation but still poo-poo its possibilities in Australia).
Rural electrification from solar is rapidly growing in Australia: FACT.
It is growing because it is economically viable: FACT.
Solar installations are becoming cheaper and are already cost-competitive with
grid (read fossil-fuel-sourced) energy. There are also huge savings involved by
localised power generation and its associated removal of need for huge
transmission line upgrading. No-one is proposing cities as energy exporters. But
as generating to fulfill their own needs? heading towards self-sufficiency?...
absolutely possible, particularly for towns and villages. After all, almost
every major Australian city sits on the coast where it can use tidal power as
all-weather back-up.
Large-scale solar thermal with molten salt storage... absolutely viable to
supply industry. Federal MP Bob Katter (that well-known radical hippy
left-winger) proposed an energy corridor from Queensland's west, feeding in from
solar installations in arid country towards the coast, powering industry along
the way. The plan was sabotaged by investing gas companies pulling out (surprise
surprise). Yes, that would need power transmission lines. But the plan he
proposed was economically viable enough to gain investors even including that
cost.
And don't tell me you believe that the populations of any Australian city would
allow the nearby construction of any form of a nuclear power plant. No, it would
be sited safely distant in the rural areas with large transmission lines
constructed to take power to the coast and industry.
Manufacturing solar panels, wind turbines etc could certainly be an export
industry to replace mining exports. Ribbon technology, cheap silicon-coated
roofing materials, modern wind turbines, all have huge marketing possibilities,
offer much cheaper technology, and could be a huge boost for the economy, just
to tackle your arguments within your paradigm.
But I believe we have to look outside the box to prevent devastating climate
change. You keep saying we can't just look to the next decade to switch from
fossil fuels. I am saying that we HAVE TO and that renewables offer our only
hope. Get on board or stop slowing us down.
cheers,
Elena
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Post by anonposter on Jun 20, 2012 5:32:30 GMT 9.5
This was post on the Green Left list. Comments? I'll see what I can come up with. Oh don't get me wrong, David. I'm all for rural electrification. If my farm was
connected to the grid I would be able to sell my surplus energy from my solar
installation, instead of having my solar panels simply switch off at 1pm in
summer once my batteries are fully charged. Which would require the rest of the population to pay higher power bills. Rural electrification from solar is rapidly growing in Australia: FACT.
It is growing because it is economically viable: FACT. If you don't have a grid connection then yes, it probably is economically viable, if you do have a grid connection it'd probably only be viable with massive subsidies (the solar market tends to crash when subsidies are abandoned, that's not something you'd expect to see if it were economically viable). Solar installations are becoming cheaper and are already cost-competitive with grid (read fossil-fuel-sourced) energy. Then why did the market collapse when feed in tariffs were ended? Could it be that solar is only actually cheaper for you when other people are paying most of the cost? Energy storage on the scale we'd need is also not solved (if you think it is then it is up to you to show how it'll be done). There are also huge savings involved by localised power generation and its associated removal of need for huge transmission line upgrading. The electricity companies in Australia seem to disagree on that point, at the very least they have made public statements that rooftop solar PV doesn't allow them to reduce investment in anything. No-one is proposing cities as energy exporters. But
as generating to fulfill their own needs? heading towards self-sufficiency?... Density is too high for rooftop solar to do that (really the only thing solar that should be on the roof of a house is a solar hot water system, those things are actually useful). absolutely possible, particularly for towns and villages. After all, almost every major Australian city sits on the coast where it can use tidal power as all-weather back-up. If you have a reliable source which can do the job and doesn't cause CO 2 emissions why are you even proposing something unreliable? Large-scale solar thermal with molten salt storage... absolutely viable to
supply industry. It technically works, though the economics are crap compared to nuclear. Federal MP Bob Katter (that well-known radical hippy left-winger) proposed an energy corridor from Queensland's west, feeding in from solar installations in arid country towards the coast, powering industry along the way. The plan was sabotaged by investing gas companies pulling out (surprise surprise). Yes, that would need power transmission lines. But the plan he proposed was economically viable enough to gain investors even including that cost. Yet investors pulled out, almost as if they thought it wasn't viable. And don't tell me you believe that the populations of any Australian city would allow the nearby construction of any form of a nuclear power plant. Most of the population isn't so much anti-nuclear as undecided and if they thought the alternative to nuclear were worse could come to accept it (though I don't think we need to build nuclear reactors in major cities, nuclear does have unmatched siting flexibility and could be built basically anywhere). No, it would be sited safely distant in the rural areas with large transmission lines
constructed to take power to the coast and industry. Most likely, in fact there are some places which already have the necessary transmission lines and even existing thermal power plants with workers already pretty much qualified to handle the balance of plant (i.e. everything except the reactor) at a nuclear power plant. I'm talking about the places which already have coal power plants, if we're to stop emitting CO 2 then those power plants must close, once the population in those places realises that they aren't going to get to keep their coal burners they'll probably be practically begging for the replacements to be built there (otherwise they'll end up ghost towns). Besides, transmission lines can easily cost as much as a power plant and engender significant local opposition along the route so using existing ones instead of building new is a good idea. Manufacturing solar panels, wind turbines etc could certainly be an export
industry to replace mining exports. For China maybe, Australia isn't likely to get much out of exporting renewable energy technology (and it's a bubble waiting to happen anyway). But I believe we have to look outside the box to prevent devastating climate
change. I believe that we should use what has been shown to actually work and so far only nuclear has been shown to have the ability to actually replace fossil fuels and be scaled up the level we need (hydro can also replace fossil fuels, but there aren't enough rivers for it to meet our needs). Get on board or stop slowing us down. Why don't you just get out of the way of those of us trying to solve global warming? |
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Post by quokka on Jun 20, 2012 12:05:58 GMT 9.5
Such a nice collection of handwaving claims, backed up by very little.
Where do you start with this stuff?
All Australian cities can use tidal power for backup? Leaving aside the cost for a moment, take the case of Brisbane, just where are you going to put this thing? Not in the mouth of the Brisbane river because it would block shipping. Most of Moreton Bay is a globally significant habitat for migratory shore birds, some of which do the annual return trip to Siberia. Shore bird populations are in serious decline and they really do not need further pressure on their habitat. Not to mention marine animals such as dugongs, turtles, dolphins etc etc. Southern Moreton Bay is a national park and some of it is Ramsar listed. The big sand islands - Stradbroke, Moreton and Bribie are mostly national park or reserve. Pumicestone Passage which might be a candidate (though I am no engineer) is a protected marine park.
The mythology that renewables have no significant environmental impact needs a good shake up. As do hand waving claims backed up by zero evidence.
As for geothermal, the only flavor that could potentially be of significance to Australia is EGS. The is no EGS of any size operating anywhere in the world. Lets at least see Geodynamics 25 MW demonstration plant running in South Australia before making any assumptions at all about it's future importance. The schedule has repeated slipped and it hasn't been for lack of government financial support.
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Post by David Walters on Jun 21, 2012 3:14:38 GMT 9.5
Thanks all for your feedback! I'll repost some of it.
David
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Post by proteos on Jun 21, 2012 18:56:16 GMT 9.5
All Australian cities can use tidal power for backup? Leaving aside the cost for a moment, take the case of Brisbane, just where are you going to put this thing? Not in the mouth of the Brisbane river because it would block shipping. Most of Moreton Bay is a globally significant habitat for migratory shore birds, some of which do the annual return trip to Siberia. Shore bird populations are in serious decline and they really do not need further pressure on their habitat. Not to mention marine animals such as dugongs, turtles, dolphins etc etc. Southern Moreton Bay is a national park and some of it is Ramsar listed. The big sand islands - Stradbroke, Moreton and Bribie are mostly national park or reserve. Pumicestone Passage which might be a candidate (though I am no engineer) is a protected marine park. That's not the only reason. In France, there is a tidal power plant. It's a 240MW plant with a dam 750m long. The Severn Barrage would be 8GW in some projects which plan much longer dams. But there's a catch: the Rance tidal plant sits in a zone with a remarkable tidal range. The tidal range varies from 8m to 12m through the year (it's the same as in the whole Mt St Michel bay). the Severn estuary is another place with similar tides. Other places like this include the Bay of Fundy and Ungava in Canada. And that's about it. I don't know how large the tides are in Australia, but I doubt they reach such heights. As a result, the dams would have to be extraordinarily large to make a real difference. |
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Post by Graham Palmer on Jun 21, 2012 19:32:49 GMT 9.5
As for geothermal, the only flavor that could potentially be of significance to Australia is EGS. The roadmap for geothermal looks like its going to be long and slow. In 2008, McLennan Magasanik were predicting that : The emerging Australian Geothermal Energy Industry can be expected to provide at least 1,000 MW and potentially up to 2,200 MW of base-load capacity by 2020 into the National Electricity Marketwww.infrastructureaustralia.gov.au/public_submissions/published/files/374_agea_SUB3.pdfContrast this with the current share value of the main Australian geothermal developers : Geodynamics, 12 cents, peaked at $2.09 in 2007 Petratherm, 5 cents, peaked at $1.44 in 2007 Hot Rock Ltd, 4 cents, peaked at 26 cents in 2007 Earth Heat Resources, 2 cents, peaked at 26 cents in 2007 Panax Geothermal, 1 cent, peaked at 26 cents in 2007 Green Rock Energy, 0.4 cents, peaked at 18 cents in 2007 Then once some plants are up and running, and generating competitively priced electricity, add another $4B or so to get connected to the NEM for a multi-gigawatt network extension to the NEM. www.aemo.com.au/~/media/Files/Other/planning/0400-0005%20pdf.pdf |
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Post by quokka on Jun 21, 2012 21:05:13 GMT 9.5
I don't know how large the tides are in Australia, but I doubt they reach such heights. As a result, the dams would have to be extraordinarily large to make a real difference. This is what Geoscience Australia (a government agency) says "Barrage-type tide energy systems generally require macro-tide ranges (greater than 4m), which are restricted to the broad northern shelf of Australia; from Port Hedland northwards to Darwin and the southern end of the Great Barrier Reef." www.ga.gov.au/energy/other-renewable-energy-resources/ocean-energy.htmlUNESCO has just delivered a scathing report on Australia's management of the Great Barrier Reef. More development would seem unwise though it will happen (for coal and gas export). As for the northwest, transmission costs would be jaw dropping. The original comment that David quoted suggested tidal as backup!!! And by the way, large slices of the Severn are also Ramsar listed and the RSPB are none too happy about the barrage proposals. |
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Post by cyrilr on Jun 21, 2012 23:34:02 GMT 9.5
Almost all energy is used in a centralized manner. The world is increasingly urbanizing.
Remote solar is useful, but not important in terms of CO2 emissions. Only a tiny fraction of global electricity is generated by remote diesel generators. It's a good market for PV to develop in, as it should be doing if it weren't for distorting subsidies in grid connected PV in Germany which is cloudy and has lots of cheap reliable coal (ie no economic case ever).
As for centralized CSP with heat storage. Technically there's a major problem, as most areas, even deserts, have large winter low solar production. A day of heat storage won't deal with that. If the industries must choose between shutting down in winter or burning fossil fuels, we can all see what will happen.
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Post by Martin Nicholson on Jun 22, 2012 8:10:44 GMT 9.5
David on the first comment from the rural farm (Elena?) not connected to the grid, the notion that her batteries are “always” fully charged by 1pm in summer seems very unlikely. With a cloudy/rainy day she might be lucky if her panels are fully charged by 4pm. By implication her batteries are not charged by 1pm in winter. The fact that she has neighbours that are connected to the grid, she probably chose not to be connected because of the $20-$30,000 it can cost to get grid connection. I would also wager that she has a backup generator that burns diesel or petrol that she needs to use some days. Rural solar with no grid connection can actually increase GHG emissions so it’s not as green as she might think.
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Post by jasonk on Jun 26, 2012 16:50:07 GMT 9.5
If she wouldn't allow large transmission lines running through her rural land between a NPP and the city then why would she support large transmission lines AND a corridor of industry to run through her rural land between the SPP and city?
It is called CONCENTRATED solar for a reason. You need a grid to get the power distributed to the users. At the beginning of the post she was bashing the grid.
There are pro's and cons to everything.
I just want to add I'm not against solar concentrated or otherwise. I just hate it when people dismiss the infrastructure issues associated with either system while simultaneously citing the same infrastructure issues as a major reason why a different energy source is the wrong one.
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Post by Singleton Engineer on Feb 23, 2017 9:21:39 GMT 9.5
This post appears to be a discussion of one potential example of a more general subject: tidal power. If such a thread is going to be started, then I suggest that a post from another Scottish engineer's site is relevant. euanmearns.com/green-mythology-adding-different-types-of-renewables-smooths-output/"The [4 times per day rapid } high frequency ramping that tidal demands can only be sensibly balanced using bespoke pumped hydro storage. The vendors of tidal energy should be required to provide this load-balancing service." The whole article and the one on the same site that preceded it puts tidal energy into broad perspective, especially as relates to Great Britain. As one who has long enjoyed and valued estuaries and the huge variety of wild life that relies on them, I perhaps am biased against tidal power, but the two articles on Energy Matters tend to support my view, which is that tidal power is expensive, environmentally damaging and not fit for integration into a network unless paired with a matched capacity of pumped hydro or other equivalent storage. It is not appropriate to rely on an assumption that sufficient capacity exists elsewhere on the grid to compensate for the predictable yet extremely variable nature of tidal power, which is only generated in 4 bursts per day of several hours' duration in the two-pond model. I agree that there are other potential models, eg using either pumped storage between ponds and/or multiple ponds that could spread the generating hours per day, but where in the world is a suitable site and at what environmental and monetary cost? |
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Post by jimbaerg on Feb 25, 2017 6:06:14 GMT 9.5
In David MacKay's discussion of tidal energy www.withouthotair.com/c14/page_81.shtmlon this page www.withouthotair.com/c14/page_86.shtmlhe claim that the tides in various good locations around Britain have their high & low outputs at different times, so the output for several tidal generating systems would be fairly constant. Whether there is another region in the world that would have similarly near constant tide generation is another matter. The amount of tide power available in Britain that he calculates would be a useful supplement rather than anywhere near the total energy needed. |
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